@article{qiu_zhang_zhang_xu_zhao_bai_zhao_wang_sheng_bloszies_et al._2024, title={Intermediate soil acidification induces highest nitrous oxide emissions}, volume={15}, ISSN={["2041-1723"]}, DOI={10.1038/s41467-024-46931-3}, abstractNote={Global potent greenhouse gas nitrous oxide (N2O) emissions from soil are accelerating, with increases in the proportion of reactive nitrogen emitted as N2O, i.e., N2O emission factor (EF). Yet, the primary controls and underlying mechanisms of EFs remain unresolved. Based on two independent but complementary global syntheses, and three field studies determining effects of acidity on N2O EFs and soil denitrifying microorganisms, we show that soil pH predominantly controls N2O EFs and emissions by affecting the denitrifier community composition. Analysis of 5438 paired data points of N2O emission fluxes revealed a hump-shaped relationship between soil pH and EFs, with the highest EFs occurring in moderately acidic soils that favored N2O-producing over N2O-consuming microorganisms, and induced high N2O emissions. Our results illustrate that soil pH has a unimodal relationship with soil denitrifiers and EFs, and the net N2O emission depends on both the N2O/(N2O + N2) ratio and overall denitrification rate. These findings can inform strategies to predict and mitigate soil N2O emissions under future nitrogen input scenarios.}, number={1}, journal={NATURE COMMUNICATIONS}, author={Qiu, Yunpeng and Zhang, Yi and Zhang, Kangcheng and Xu, Xinyu and Zhao, Yunfeng and Bai, Tongshuo and Zhao, Yexin and Wang, Hao and Sheng, Xiongjie and Bloszies, Sean and et al.}, year={2024}, month={Mar} }
 @article{ye_li_gui_zhu_zhou_li_jiao_griffiths_hu_liu_2024, title={Long-term organic amendments increase the vulnerability of microbial respiration to environmental changes: Evidence from field and laboratory studies}, volume={920}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2024.170979}, abstractNote={Organic amendments can improve soil fertility and microbial diversity, making agroecosystems more resilient to stress. However, it is uncertain whether organic amendments will enhance the functional capacity of soil microbial communities, thereby mitigating fluctuations in microbial respiration caused by environmental changes. Here, we examined the impacts of long-term organic amendments on the dynamics of microbial catabolic capacity (characterized by enzyme activities and carbon source utilization) and microbial respiration, as well as their interrelationships during a period with fluctuating temperature and rainfall in the field. We then subjected the field soil samples to laboratory heating disturbances to further evaluate the importance of microbial catabolic capacity in explaining patterns of microbial respiration. In both field and laboratory experiments, organic amendments tended to increase the stability of microbial catabolic capacity, but significantly increased the vulnerability of microbial respiration to environmental changes. However, the direction and driving factors of microbial respiration affected by environmental changes differed between the field and laboratory experiments. Environmental changes in the field suppressed the promotional effects of organic amendments on microbial respiration mainly through reducing microbial catabolic capacity, while laboratory heating further enhanced microbial respiration mainly due to increased soil resource availability. Together, these findings suggest that increased microbial respiration variations under organic amendments may potentially increase the uncertainty in predicting soil carbon emissions in the scenario of ongoing climate/anthropogenic changes, and highlight the necessity of linking laboratory studies on environmental changes to field conditions.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Ye, Chenglong and Li, Na and Gui, Juan and Zhu, Mengyi and Zhou, Yan and Li, Daming and Jiao, Kuihu and Griffiths, Bryan S. and Hu, Shuijin and Liu, Manqiang}, year={2024}, month={Apr} }
 @article{bai_qiu_hu_2024, title={Nitrogen availability mediates the effects of roots and mycorrhizal fungi on soil organic carbon decomposition: A meta-analysis}, volume={34}, ISSN={["2210-5107"]}, DOI={10.1016/j.pedsph.2024.02.007}, abstractNote={Plant roots and their associated mycorrhizal fungi critically mediate decomposition of soil organic carbon (C), but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain unclear. Based on a synthesis of 596 paired observations from both field and greenhouse experiments, we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%, but low soil N availability (i.e., high soil C:N ratio) critically mitigated this promotion effect. Also, the positive effect of living roots and/or mycorrhizal fungi on organic C decomposition was higher under herbaceous and leguminous plants than under woody and non-leguminous plants, respectively. Surprisingly, there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C decomposition. Further, roots and/or mycorrhizal fungi significantly enhanced decomposition of leaf litter, but not root litter. Together, these results advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.}, number={2}, journal={PEDOSPHERE}, author={Bai, Tongshuo and Qiu, Yunpeng and Hu, Shuijin}, year={2024}, month={Apr}, pages={289–296} }
 @article{hu_delgado-baquerizo_fanin_chen_zhou_du_hu_jiang_hu_liu_2024, title={Nutrient-induced acidification modulates soil biodiversity-function relationships}, volume={15}, ISSN={["2041-1723"]}, DOI={10.1038/s41467-024-47323-3}, abstractNote={Nutrient enrichment is a major global change component that often disrupts the relationship between aboveground biodiversity and ecosystem functions by promoting species dominance, altering trophic interactions, and reducing ecosystem stability. Emerging evidence indicates that nutrient enrichment also reduces soil biodiversity and weakens the relationship between belowground biodiversity and ecosystem functions, but the underlying mechanisms remain largely unclear. Here, we explore the effects of nutrient enrichment on soil properties, soil biodiversity, and multiple ecosystem functions through a 13-year field experiment. We show that soil acidification induced by nutrient enrichment, rather than changes in mineral nutrient and carbon (C) availability, is the primary factor negatively affecting the relationship between soil diversity and ecosystem multifunctionality. Nitrogen and phosphorus additions significantly reduce soil pH, diversity of bacteria, fungi and nematodes, as well as an array of ecosystem functions related to C and nutrient cycling. Effects of nutrient enrichment on microbial diversity also have negative consequences at higher trophic levels on the diversity of microbivorous nematodes. These results indicate that nutrient-induced acidification can cascade up its impacts along the soil food webs and influence ecosystem functioning, providing novel insight into the mechanisms through which nutrient enrichment influences soil community and ecosystem properties.}, number={1}, journal={NATURE COMMUNICATIONS}, author={Hu, Zhengkun and Delgado-Baquerizo, Manuel and Fanin, Nicolas and Chen, Xiaoyun and Zhou, Yan and Du, Guozhen and Hu, Feng and Jiang, Lin and Hu, Shuijin and Liu, Manqiang}, year={2024}, month={Apr} }
 @article{chen_huang_hu_wang_hu_2024, title={Precipitation- rather than temperature-driven pattern in belowground biomass and root:shoot ratio across the Qinghai-Tibet Plateau}, volume={915}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2024.170158}, abstractNote={The Qinghai-Tibet Plateau faces dramatic global change, which can greatly affect its plant growth, biomass accumulation, and carbon cycling. However, it is still unclear how belowground plant biomass, which is the major part of vegetation biomass on the plateau, changes with different environmental factors, impeding accurate prediction of ecosystem carbon cycling under future global change scenarios. To reveal the patterns of belowground biomass and root:shoot ratio with environmental factors in different vegetation types on the Qinghai-Tibet Plateau, we synthesized data for 158 sites from 167 publications, including 585 and 379 observations for above- and below-ground biomass, respectively. Data on temperature, precipitation, soil nitrogen content, evapotranspiration and solar radiation were collected from open databases. The results showed that precipitation, rather than temperature, was closely associated with other environmental factors including soil N and solar radiation. Also, both above- and below-ground biomass significantly increased with annual precipitation and its related environmental factors, while elevation-related coldness only slightly decreased aboveground biomass. In addition, the positive effect of precipitation on belowground biomass is more obvious in higher elevations (colder areas). As a result, root:shoot ratio significantly increased with precipitation in colder areas but not in warmer areas. Finally, the positive relationship between biomass and precipitation was stronger for dryer steppes than for wetter meadows and shrublands. Our findings indicate that precipitation, as well as the associated nitrogen availability and solar radiation, together are more important drivers than temperature for ecosystem productivity and biomass allocation on the Qinghai-Tibet Plateau. Given the heterogeneous trend of precipitation change on the plateau, productivity response to global change can be highly variable across different regions and vegetation types, which can consequently impact soil carbon dynamics and regional carbon cycling.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Chen, Sihan and Huang, Kailing and Hu, Lingyan and Wang, Peng and Hu, Shuijin}, year={2024}, month={Mar} }
 @article{su_mei_mendes_tian_zhou_hu_li_2023, title={Alkalinity exacerbates phosphorus deficiency in subtropical red soils: Insights from phosphate-solubilizing fungi}, volume={5}, ISSN={["1475-2743"]}, DOI={10.1111/sum.12911}, abstractNote={Abstract}, journal={SOIL USE AND MANAGEMENT}, author={Su, Mu and Mei, Jiajie and Mendes, Gilberto de Oliveira and Tian, Da and Zhou, Limin and Hu, Shuijin and Li, Zhen}, year={2023}, month={May} }
 @article{qiu_zhang_zhao_zhao_wang_wang_he_xu_bai_zhang_et al._2023, title={Climate warming suppresses abundant soil fungal taxa and reduces soil carbon efflux in a semi-arid grassland}, volume={2}, ISSN={["2770-100X"]}, DOI={10.1002/mlf2.12098}, abstractNote={Abstract}, number={4}, journal={MLIFE}, author={Qiu, Yunpeng and Zhang, Kangcheng and Zhao, Yunfeng and Zhao, Yexin and Wang, Bianbian and Wang, Yi and He, Tangqing and Xu, Xinyu and Bai, Tongshuo and Zhang, Yi and et al.}, year={2023}, month={Dec}, pages={389–400} }
 @article{xu_zhang_zhang_li_xia_xiao_liang_lei_he_chen_et al._2023, title={Coupled anaerobic methane oxidation and metal reduction in soil under elevated CO2}, volume={5}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.16763}, abstractNote={Abstract}, journal={GLOBAL CHANGE BIOLOGY}, author={Xu, Chenchao and Zhang, Naifang and Zhang, Kaihang and Li, Shuyao and Xia, Qing and Xiao, Jing and Liang, Maojun and Lei, Weilei and He, Junpan and Chen, Gaiping and et al.}, year={2023}, month={May} }
 @article{ye_wu_bai_zhou_guo_du_hu_2023, title={Interannual variation in precipitation predominantly controls mineral-associated organic carbon dynamics in a Tibetan alpine meadow}, volume={433}, ISSN={["1872-6259"]}, DOI={10.1016/j.geoderma.2023.116432}, abstractNote={Soils in alpine ecosystems store a large amount of organic carbon (C) with a significant portion sorbed to reactive soil minerals. However, impacts of ongoing global change factors on mineral-associated organic C dynamics are highly uncertain in alpine regions. Utilizing a multi-factor simulation experiment in a Tibetan alpine meadow since May 2015, we examined the effects of air warming, nitrogen input and precipitation changes on calcium (Ca)- and iron (Fe)-associated C dynamics in 2019–2020. We found no significant difference in Ca- or Fe-associated C concentrations among treatments. However, both Ca- and Fe-associated C concentrations were significantly higher in 2020 with abnormally high rainfall (+40%) than in 2019 with normal rainfall. High rainfall significantly increased soil moisture, reduced soil aggregation and released soil dissolved organic C. High soil moisture promoted the formation of both Ca- and Fe-associated C, likely through facilitating Ca-binding to clay surface as a bridge for mineral-C complexes or through increasing solubility of Fe oxides. In contrast, a low degree of water addition (<30%) immediately following each rainfall event in field did not significantly affect either Ca- or Fe-associated C. Taken together, our results provide new insights into the potential mechanisms through which interannual precipitation variability controls mineral-associated C persistence in alpine meadow ecosystems, suggesting that the pattern of rainfall change may dominate its impact on dynamics of organic C retained by reactive minerals.}, journal={GEODERMA}, author={Ye, Chenglong and Wu, Bin and Bai, Tongshuo and Zhou, Xianhui and Guo, Hui and Du, Guozhen and Hu, Shuijin}, year={2023}, month={May} }
 @article{zhang_qiu_zhao_wang_deng_chen_xu_wang_bai_he_et al._2023, title={Moderate precipitation reduction enhances nitrogen cycling and soil nitrous oxide emissions in a semi-arid grassland}, volume={3}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.16672}, abstractNote={Abstract}, journal={GLOBAL CHANGE BIOLOGY}, author={Zhang, Kangcheng and Qiu, Yunpeng and Zhao, Yunfeng and Wang, Shuhong and Deng, Jun and Chen, Mengfei and Xu, Xinyu and Wang, Hao and Bai, Tongshuo and He, Tangqing and et al.}, year={2023}, month={Mar} }
 @article{li_yu_hao_qiu_hu_2023, title={Mycorrhizae enhance reactive minerals but reduce mineral-associated carbon}, volume={7}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.16886}, abstractNote={Abstract}, journal={GLOBAL CHANGE BIOLOGY}, author={Li, Huan and Yu, Guang-Hui and Hao, Liping and Qiu, Yunpeng and Hu, Shuijin}, year={2023}, month={Jul} }
 @article{bai_wang_qiu_zhang_hu_2023, title={Nitrogen availability mediates soil carbon cycling response to climate warming: A meta-analysis}, volume={2}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.16627}, abstractNote={Abstract}, journal={GLOBAL CHANGE BIOLOGY}, author={Bai, Tongshuo and Wang, Peng and Qiu, Yunpeng and Zhang, Yi and Hu, Shuijin}, year={2023}, month={Feb} }
 @article{zhao_wang_smith_hu_liu_tao_ma_averill_freschet_crowther_et al._2023, title={Nitrogen redistribution and seasonal trait fluctuation facilitate plant N conservation and ecosystem N retention}, volume={12}, ISSN={["1365-2745"]}, DOI={10.1111/1365-2745.14246}, abstractNote={Abstract}, journal={JOURNAL OF ECOLOGY}, author={Zhao, Qingzhou and Wang, Peng and Smith, Gabriel Reuben and Hu, Lingyan and Liu, Xupeng and Tao, Tingting and Ma, Miaojun and Averill, Colin and Freschet, Gregoire T. and Crowther, Thomas W. and et al.}, year={2023}, month={Dec} }
 @article{wang_huang_song_yuan_li_zhu_chang_luo_ciais_penuelas_et al._2023, title={Reduced phosphorus availability in paddy soils under atmospheric CO2 enrichment}, volume={1}, ISSN={["1752-0908"]}, DOI={10.1038/s41561-022-01105-y}, abstractNote={Phosphorus is an essential element for plant metabolism and growth, but its future supply under elevated levels of atmospheric CO2 remains uncertain. Here we present measurements of phosphorus concentration from two long-term (15 and 9 years) rice free air carbon dioxide enrichment experiments. Although no changes were observed in the initial year of the experiments, by the end of the experiments soil available phosphorus had declined by more than 20% (26.9% and 21.0% for 15 and 9 years, respectively). We suggest that the reduction can be explained by the production of soil organic phosphorus that is not in a readily plant-available form, as well as by increased removal through crop harvest. Our findings further suggest that increased transfers of plant available phosphorus from biological, biochemical and chemical phosphorus under anthropogenic changes are insufficient to compensate for reductions to plant available phosphorus under long-term exposure to elevated CO2. We estimate that reductions to rice yields could be particularly acute in low-income countries under future CO2 scenarios without the input of additional phosphorus fertilizers to compensate, despite the potentially reduced global risk for phosphorus pollution. Plant-available phosphorus declines in paddy soils as atmospheric CO2 increases, according to long-term free air carbon dioxide enrichment experiments of rice plants.}, journal={NATURE GEOSCIENCE}, author={Wang, Yu and Huang, Yuanyuan and Song, Lian and Yuan, Jiahui and Li, Wei and Zhu, Yongguan and Chang, Scott X. and Luo, Yiqi and Ciais, Philippe and Penuelas, Josep and et al.}, year={2023}, month={Jan} }
 @misc{liu_sayer_deng_li_liu_wang_yang_huang_luo_su_et al._2023, title={The grassland carbon cycle: Mechanisms, responses to global changes, and potential contribution to carbon neutrality}, volume={3}, ISSN={["2667-3258"]}, DOI={10.1016/j.fmre.2022.09.028}, abstractNote={Grassland is one of the largest terrestrial biomes, providing critical ecosystem services such as food production, biodiversity conservation, and climate change mitigation. Global climate change and land-use intensification have been causing grassland degradation and desertification worldwide. As one of the primary medium for ecosystem energy flow and biogeochemical cycling, grassland carbon (C) cycling is the most fundamental process for maintaining ecosystem services. In this review, we first summarize recent advances in our understanding of the mechanisms underpinning spatial and temporal patterns of the grassland C cycle, discuss the importance of grasslands in regulating inter- and intra-annual variations in global C fluxes, and explore the previously unappreciated complexity in abiotic processes controlling the grassland C balance, including soil inorganic C accumulation, photochemical and thermal degradation, and wind erosion. We also discuss how climate and land-use changes could alter the grassland C balance by modifying the water budget, nutrient cycling and additional plant and soil processes. Further, we examine why and how increasing aridity and improper land use may induce significant losses in grassland C stocks. Finally, we identify several priorities for future grassland C research, including improving understanding of abiotic processes in the grassland C cycle, strengthening monitoring of grassland C dynamics by integrating ground inventory, flux monitoring, and modern remote sensing techniques, and selecting appropriate plant species combinations with suitable traits and strong resistance to climate fluctuations, which would help design sustainable grassland restoration strategies in a changing climate.}, number={2}, journal={FUNDAMENTAL RESEARCH}, author={Liu, Lingli and Sayer, Emma J. and Deng, Meifeng and Li, Ping and Liu, Weixing and Wang, Xin and Yang, Sen and Huang, Junsheng and Luo, Jie and Su, Yanjun and et al.}, year={2023}, month={Mar}, pages={209–218} }
 @article{deng_hu_guo_jiang_huang_schmid_liu_chang_li_liu_et al._2023, title={Tree mycorrhizal association types control biodiversity- relationship in a subtropical forest}, volume={9}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.add4468}, abstractNote={Mycorrhizae are symbiotic associations between terrestrial plants and fungi in which fungi obtain nutrients in exchange for plant photosynthates. However, it remains unclear how different types of mycorrhizae affect their host interactions and productivity. Using a long-term experiment with a diversity gradient of arbuscular (AM) and ectomycorrhizal (EcM) tree species, we show that the type of mycorrhizae critically controls the effect of diversity on productivity. With increasing diversity, the net primary production of AM trees increased, but EcM trees decreased, largely because AM trees are more effective in acquiring nitrogen and phosphorus. Specifically, with diversity increase, AM trees enhance both nutrient resorption and litter decomposition, while there was a trade-off between litter decomposability and nutrient resorption in EcM trees. These results provide a mechanistic understanding of why AM trees using a different nutrient acquisition strategy from EcM trees can dominate in subtropical forests and at the same time their diversity enhances productivity.}, number={3}, journal={SCIENCE ADVANCES}, author={Deng, Meifeng and Hu, Shuijin and Guo, Lulu and Jiang, Lin and Huang, Yuanyuan and Schmid, Bernhard and Liu, Chao and Chang, Pengfei and Li, Shan and Liu, Xiaojuan and et al.}, year={2023}, month={Jan} }
 @article{zhang_qiu_gilliam_gillespie_tu_reberg-horton_hu_2022, title={Arbuscular Mycorrhizae Shift Community Composition of N-Cycling Microbes and Suppress Soil N2O Emission}, volume={8}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.2c03816}, abstractNote={Mycorrhizae are ubiquitous symbiotic associations between arbuscular mycorrhizal fungi (AMF) and terrestrial plants, in which AMF receive photosynthates from and acquire soil nutrients for their host plants. Plant uptake of soil nitrogen (N) reduces N substrate for microbial processes that generate nitrous oxide (N2O), a potent greenhouse gas. However, the underlying microbial mechanisms remain poorly understood, particularly in agroecosystems with high reactive N inputs. We examined how plant roots and AMF affect N2O emissions, N2O-producing (nirK and nirS) and N2O-consuming (nosZ) microbes under normal and high N inputs in conventional (CONV) and organically managed (OM) soils. Here, we show that high N input increased soil N2O emissions and the ratio of nirK to nirS microbes. Roots and AMF did not affect the (nirK + nirS)/nosZ ratio but significantly reduced N2O emissions and the nirK/nirS ratio. They reduced the nirK/nirS ratio by reducing nirK-Rhodobacterales but increasing nirS-Rhodocyclales in the CONV soil while decreasing nirK-Burkholderiales but increasing nirS-Rhizobiales in the OM soil. Our results indicate that plant roots and AMF reduced N2O emission directly by reducing soil N and indirectly through shifting the community composition of N2O-producing microbes in N-enriched agroecosystems, suggesting that harnessing the rhizosphere microbiome through agricultural management might offer additional potential for N2O emission mitigation.}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Zhang, Xuelin and Qiu, Yunpeng and Gilliam, Frank S. and Gillespie, Christopher J. and Tu, Cong and Reberg-Horton, S. Chris and Hu, Shuijin}, year={2022}, month={Aug} }
 @article{ye_huang_hall_hu_2022, title={Association of Organic Carbon With Reactive Iron Oxides Driven by Soil pH at the Global Scale}, volume={36}, ISSN={["1944-9224"]}, DOI={10.1029/2021GB007128}, abstractNote={Abstract}, number={1}, journal={GLOBAL BIOGEOCHEMICAL CYCLES}, author={Ye, Chenglong and Huang, Wenjuan and Hall, Steven J. and Hu, Shuijin}, year={2022}, month={Jan} }
 @article{hu_sai_guo_guo_zhou_hu_wang_2022, title={Effects of an actinorhizal shrub on the nitrogen status of the soil and neighboring plants in an alpine meadow of the Tibetan Plateau}, volume={8}, ISSN={["1664-221X"]}, DOI={10.1007/s00035-022-00287-w}, journal={ALPINE BOTANY}, author={Hu, Lingyan and Sai, Jiuma and Guo, Jin and Guo, Hui and Zhou, Xianhui and Hu, Shuijin and Wang, Peng}, year={2022}, month={Aug} }
 @article{wang_mou_hu_hu_2022, title={Effects of nutrient heterogeneity on root foraging and plant growth at the individual and community level}, volume={9}, ISSN={["1460-2431"]}, DOI={10.1093/jxb/erac358}, abstractNote={Abstract}, journal={JOURNAL OF EXPERIMENTAL BOTANY}, author={Wang, Peng and Mou, Pu and Hu, Lingyan and Hu, Shuijin}, year={2022}, month={Sep} }
 @article{zhang_zhang_hu_2022, title={Fungivorous nematode Aphelenchus avenae and collembola Hypogastrura perplexa alleviate damping-off disease caused by Pythium ultimum in tomato}, volume={9}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-022-05680-2}, journal={PLANT AND SOIL}, author={Zhang, Pei and Zhang, Weijian and Hu, Shuijin}, year={2022}, month={Sep} }
 @article{bloszies_reberg-horton_heitman_woodley_grossman_hu_2022, title={Legume cover crop type and termination method effects on labile soil carbon and nitrogen and aggregation}, volume={4}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.21022}, DOI={10.1002/agj2.21022}, abstractNote={Abstract}, number={3}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Bloszies, Sean A. and Reberg-Horton, S. Chris and Heitman, Joshua L. and Woodley, Alex L. and Grossman, Julie M. and Hu, Shuijin}, year={2022}, month={Apr} }
 @article{wu_chen_delgado-baquerizo_liu_wang_wu_hu_bai_2022, title={Long-term regional evidence of the effects of livestock grazing on soil microbial community structure and functions in surface and deep soil layers}, volume={168}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2022.108629}, abstractNote={Grazing by livestock can affect plant biodiversity and topsoil functions. However, experimental evidence on whether these impacts are limited to the topsoil or penetrate into deep layers (via changes in soil environment and resource locations) of soil is lacking, especially for soil microbial biomass and diversity. Here, we used paired grazed and ungrazed (fenced) plots at 10 locations across the Mongolian Plateau to investigate how long-term (>10 years) livestock grazing affects the biomass, diversity, composition, and function of microbial communities in surface (0–20 cm) and deep soil layers (40–60 cm). Livestock grazing increased bacterial diversity by 5–9% in both soil layers but increased fungal diversity by 10% only in the topsoil. Livestock grazing also strongly altered bacterial and fungal community composition in both soil layers. Livestock grazing decreased soil C mineralization rates by 11–25% in both soil layers, and decreased soil N mineralization rates by 16% and bacterial biomass by 20% only in the topsoil. The grazing-induced increase in microbial diversity in both soil layers was mainly explained by the changes in plant C:N ratio and plant biomass rather than by soil abiotic variables, especially for the deep soil layer. The grazing-induced negative effects on ecosystem functions (soil C and N mineralization) were mainly associated with soil abiotic variables together with plant variables or microbial diversity in the surface soil layer and were mainly associated with plant variables and soil microbial diversity in the deep soil layer. Overall, our regional field experiment provides the first evidence that the strong effects of livestock grazing on soil microbial biomass, diversity, composition, and function can penetrate the deep soil in arid and semi-arid grasslands. This knowledge suggests that models should consider the dynamic interactions between land use and both soil microbial diversity and biomass across soil depths in global drylands. Conceptual diagram showing the effects of livestock grazing on the soil microbial community structure and functions in surface and deep soil layers on the Mongolia Plateau. We investigated how large herbivore grazing affects biomass and diversities of soil bacterial and fungal communities and ecosystem functions in both surface and deep soil layers using paired grazed and ungrazed plots at 10 locations across the Mongolian Plateau. Our results provide the first evidence that the strong effects of livestock grazing on soil microbial biomass, diversity, composition, and function can penetrate to a deep soil layer on arid and semi-arid grasslands. The findings suggest that models should consider the dynamic interactions between land use and both soil microbial biomass and diversity across soil depths in global drylands. • Livestock grazing increased soil bacterial diversity in both topsoil and deep soils. • Livestock grazing increased soil fungal diversity only in the topsoil. • Livestock grazing decreased soil bacterial biomass only in the topsoil. • Grazing effects on soil bacteria were stronger than on soil fungi across soil depths. • Grazing effects on soil microbes and functions can penetrate the deeper soils.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Wu, Ying and Chen, Dima and Delgado-Baquerizo, Manuel and Liu, Shengen and Wang, Bing and Wu, Jianping and Hu, Shuijin and Bai, Yongfei}, year={2022}, month={May} }
 @article{yan_kohli_wen_wang_zhang_yang_zhou_du_hu_guo_2022, title={Nitrogen addition and warming modulate the pathogen impact on plant biomass by shifting intraspecific functional traits and reducing species richness}, volume={12}, ISSN={["1365-2745"]}, DOI={10.1111/1365-2745.14043}, abstractNote={Abstract}, journal={JOURNAL OF ECOLOGY}, author={Yan, Xuebin and Kohli, Mayank and Wen, Yue and Wang, Xiaoyi and Zhang, Yuanyuan and Yang, Fei and Zhou, Xianhui and Du, Guozhen and Hu, Shuijin and Guo, Hui}, year={2022}, month={Dec} }
 @article{xie_ren_chen_yang_zheng_chen_wang_li_hu_xu_2022, title={Plant nitrogen nutrition: The roles of arbuscular mycorrhizal fungi}, volume={269}, ISSN={["1618-1328"]}, DOI={10.1016/j.jplph.2021.153591}, abstractNote={Nitrogen (N) is the most abundant mineral nutrient required by plants, and crop productivity depends heavily on N fertilization in many soils. Production and application of N fertilizers consume huge amounts of energy and substantially increase the costs of agricultural production. Excess N compounds released from agricultural systems are also detrimental to the environment. Thus, increasing plant N uptake efficiency is essential for the development of sustainable agriculture. Arbuscular mycorrhizal (AM) fungi are beneficial symbionts of most terrestrial plants that facilitate plant nutrient uptake and increase host resistance to diverse environmental stresses. AM association is an endosymbiotic process that relies on the differentiation of both host plant roots and AM fungi to create novel contact interfaces within the cells of plant roots. AM plants have two pathways for nutrient uptake: either direct uptake via the root hairs and root epidermis, or indirectly through AM fungal hyphae into root cortical cells. Over the last few years, great progress has been made in deciphering the molecular mechanisms underlying the AM-mediated modulation of nutrient uptake processes, and a growing number of fungal and plant genes responsible for the uptake of nutrients from soil or transfer across the fungi-root interface have been identified. Here, we mainly summarize the recent advances in N uptake, assimilation, and translocation in AM symbiosis, and also discuss how N interplays with C and P in modulating AM development, as well as the synergies between AM fungi and soil microbial communities in N uptake.}, journal={JOURNAL OF PLANT PHYSIOLOGY}, author={Xie, Kun and Ren, Yuhan and Chen, Aiqun and Yang, Congfan and Zheng, Qingsong and Chen, Jun and Wang, Dongsheng and Li, Yiting and Hu, Shuijin and Xu, Guohua}, year={2022}, month={Feb} }
 @article{cheng_li_zhang_lu_chen_yao_dong_ma_yuan_xu_et al._2021, title={Autopolyploidy-driven range expansion of a temperate-originated plant to pan-tropic under global change}, volume={91}, ISSN={["1557-7015"]}, DOI={10.1002/ecm.1445}, abstractNote={Abstract}, number={2}, journal={ECOLOGICAL MONOGRAPHS}, author={Cheng, Jiliang and Li, Jun and Zhang, Zheng and Lu, Huan and Chen, Guoqi and Yao, Beibei and Dong, Yingxue and Ma, Ling and Yuan, Xiaoxiao and Xu, Jingxuan and et al.}, year={2021}, month={May} }
 @article{li_wang_su_wang_li_bai_wei_liu_chen_zhu_et al._2021, title={Climate change drivers alter root controls over litter decomposition in a semi-arid grassland}, volume={158}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2021.108278}, abstractNote={Plant roots are the primary source of soil organic carbon (C) and critically support the growth and activities of microbes in the rhizosphere. Climate change factors may, however, modify root-microbial interactions and impact C dynamics in the rhizosphere. Yet, the direction and magnitude of interactive climate change effects, as well as the underlying mechanisms, remain unclear. Here we show evidence from a field experiment demonstrating that warming and precipitation changes strengthen root controls over litter decomposition in a semi-arid grassland. While warming and precipitation reduction suppressed microbial decomposition of root litter regardless of the root presence, precipitation increase stimulated litter decomposition only in the absence of roots, suggesting that plant competition for water constraints the activities of saprophytic microbes. Root presence increased microbial biomass but reduced microbial activities such as respiration, C cycling enzymes and litter decomposition, indicating that roots exert differential effects on microbes through altering C or water availability. In addition, nitrogen (N) input significantly reduced microbial biomass and microbial activities (respiration). Together, these results showed that alterations in soil moisture induced by climate change drivers critically modulate root controls over microbial decomposition in soil. Our findings suggest that warming-enhanced plant water utilization, combined with N-induced suppression of microbes, may provide a unique mechanism through which moderate increases in precipitation, warming and N input interactively suppress microbial decomposition, thereby facilitating short-term soil C sequestration in the arid and semi-arid grasslands.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Li, Zhen and Wang, Fuwei and Su, Fanglong and Wang, Peng and Li, Shijie and Bai, Tongshuo and Wei, Yanan and Liu, Manqiang and Chen, Dima and Zhu, Weixing and et al.}, year={2021}, month={Jul} }
 @article{xu_qiu_zhang_yang_chen_luo_yan_wang_zhang_chen_et al._2021, title={Climate warming promotes deterministic assembly of arbuscular mycorrhizal fungal communities}, volume={11}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.15945}, abstractNote={Abstract}, journal={GLOBAL CHANGE BIOLOGY}, author={Xu, Xinyu and Qiu, Yunpeng and Zhang, Kangcheng and Yang, Fei and Chen, Mengfei and Luo, Xi and Yan, Xuebin and Wang, Peng and Zhang, Yi and Chen, Huaihai and et al.}, year={2021}, month={Nov} }
 @article{li_zhang_sun_hu_wang_hu_li_xu_jiao_2021, title={Combination of plant-growth-promoting and fluoranthene-degrading microbes enhances phytoremediation efficiency in the ryegrass rhizosphere}, volume={28}, ISSN={["1614-7499"]}, DOI={10.1007/s11356-020-10937-3}, abstractNote={Plant- and/or microbe-based systems can provide a cost-effective, sustainable means to remove contaminants from soil. Microbe-assisted phytoremediation has potential utility for polycyclic aromatic hydrocarbons such as fluoranthene (Flu) removal from soils; however, the efficiency varies with the plant and microbes used. This study evaluated the Flu removal efficiency in a system with ryegrass (Lolium multiflorum), an IAA-producing Arthrobacter pascens strain (ZZ21), and/or a Flu-degrading Bacillus cereus strain (Z21). Strain ZZ21 significantly enhanced the growth of ryegrass. Ryegrass in combination with both strains (FIP) was the most effective method for Flu removal. By day 60, 74.9% of the Flu was depleted in the FIP treatment, compared with 21.1% in the control (CK), 63.7% with ryegrass alone (P), 69.0% for ryegrass with ZZ21 (IP), and 72.6% for ryegrass with Z21 (FP). FIP treatment promoted ryegrass growth, accelerated Flu accumulation in plants, and increased soil microbial counts. Microbial carbon utilization was significantly higher in soil in the FIP than with the CK treatment. Principal component analysis of the distribution of carbon substrate utilization showed that microbial functional profiles diverged among treatments, and this divergence became more profound at day 60 than day 30. Microbial inoculation significantly enhanced microbial utilization of phenols. Microbes in the FIP soil dominantly utilized amines/amides and phenols at day 30 but shifted to carbohydrates by day 60. Together, the combination of IAA-producing microbes and Flu-degrading microbes could promote plant growth, facilitate Flu degradation, and change soil microbial functional structure.}, number={5}, journal={ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH}, author={Li, Weiming and Zhang, Zhen and Sun, Bin and Hu, Shuijin and Wang, Dongsheng and Hu, Feng and Li, Huixin and Xu, Li and Jiao, Jiaguo}, year={2021}, month={Feb}, pages={6068–6077} }
 @article{bai_wang_ye_hu_2021, title={Form of nitrogen input dominates N effects on root growth and soil aggregation: A meta-analysis}, volume={157}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2021.108251}, abstractNote={Anthropogenic nitrogen (N) input has overtaken natural N fixation as the largest reactive N source and is predicted to stimulate ecosystem carbon (C) sequestration. Most studies of N effects on soil C balance have focused on biological processes that control C input (plant production) and C output (microbial decomposition), but few have examined the general patterns of N effects on the physiochemical processes that regulate soil organic C persistence. We synthesized results from 87 publications that examined effects of experimental N input on soil aggregation, a key process controlling soil C persistence, and its related processes. Globally, N input significantly enhanced plant shoot and root biomass, and the formation of soil macroaggregates and their size (measured as mean weight diameter, MWD; P < 0.05). Surprisingly, N-enhancement of root biomass and soil aggregation primarily stemmed from urea applications. Although urea input reduced microaggregates, it increased macroaggregates (+6.9%) and MWD, likely due to enmeshment by urea-induced root growth (+20.5%). In contrast, other forms of N input (combined NH4+, NO3− and NH4NO3) did not significantly affect root biomass, microaggregates or macroaggregates, but reduced microbial biomass C. Further, N-promotion of soil aggregation occurred mainly in croplands under low to moderate N input (<200 kg N ha−1 yr−1). Together, these results indicate that the form of N fertilizer exerts a primary control over N effects on plants, microbes, and soil aggregation. Our findings suggest that combination of urea fertilizers and reduced perturbations (e.g., reduced-tillage) may be key to enhance soil aggregation and organic C retention and persistence in vast agroecosystems.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Bai, Tongshuo and Wang, Peng and Ye, Chenglong and Hu, Shuijin}, year={2021}, month={Jun} }
 @article{wang_wu_chen_hu_bai_2021, title={Legacy effect of grazing intensity mediates the bottom-up controls of resource addition on soil food webs}, volume={58}, ISSN={["1365-2664"]}, DOI={10.1111/1365-2664.13825}, abstractNote={Abstract}, number={5}, journal={JOURNAL OF APPLIED ECOLOGY}, author={Wang, Bing and Wu, Ying and Chen, Dima and Hu, Shuijin and Bai, Yongfei}, year={2021}, month={May}, pages={976–987} }
 @article{liu_bei_wang_liu_hu_lin_zhang_lin_jin_hu_et al._2021, title={Microbial metabolic efficiency and community stability in high and low fertility soils following wheat residue addition}, volume={159}, ISSN={["1873-0272"]}, DOI={10.1016/j.apsoil.2020.103848}, abstractNote={Soil microbial metabolic efficiency and microbial community stability following the amendment of plant residue to soils are of great importance to the improvement of soil carbon storage and soil fertility. However, heterogeneity of microbial metabolic efficiency and community stability in soils with different fertility defined based on the crop yield, as well as the underlying mechanisms still remains elusive. Here, soils with high and low fertility (HF and LF) were incubated with 13C-labeled wheat residue and analyzed periodically for microbial metabolic quotient and functional bacterial populations using DNA-stable isotope probing technique combined with high-throughput sequencing. Results revealed that soil organic matter (SOM) decomposers following wheat residue amendment were suppressed in HF but stimulated in LF, leading to a higher microbial metabolic efficiency and lower priming effect in HF. This difference in SOM decomposers' responses could be due to that microbes in nutrient- limited LF has to mine recalcitrant SOM for nutrient requirement to support the utilization of wheat residue, the ample nutrients in HF, however, render the microbes to directly utilize wheat residue. Both the resistance (disturbance stability) and resilience (temporal stability) of bacterial community were higher in HF than in LF following disturbance of wheat residue addition. Higher abundance and lower composition variation of wheat residue decomposers in HF than in LF might result in the higher stability of microbial community in HF. The results suggest that plant residue amendment to fertile soils is likely more effective for soil carbon accumulation and soil fertility buildup than to infertile soils, due to higher microbial metabolic efficiency and higher microbial community stability.}, journal={APPLIED SOIL ECOLOGY}, author={Liu, Benjuan and Bei, Qicheng and Wang, Xiaojie and Liu, Qi and Hu, Shuijin and Lin, Zhibin and Zhang, Yanhui and Lin, Xingwu and Jin, Haiyang and Hu, Tianlong and et al.}, year={2021}, month={Mar} }
 @article{yang_zhang_barberan_yang_hu_guo_2021, title={Nitrogen-induced acidification plays a vital role driving ecosystem functions: Insights from a 6-year nitrogen enrichment experiment in a Tibetan alpine meadow}, volume={153}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2020.108107}, abstractNote={Anthropogenic nitrogen (N) input has overtaken natural N fixation as the leading source of reactive N, and can profoundly alter the structure and functions of terrestrial ecosystems. N input impacts ecosystem functions through altering abiotic (e.g., soil nutrients and pH) and biotic (e.g., biological community composition) properties, but the relative importance of these abiotic and biotic effects remains largely unknown. We conducted a 6-year experiment of N manipulations (0, 5, 10, and 20 g N m−2 yr−1) in a Tibetan alpine meadow to assess N-induced abiotic and biotic effects on ecosystem functions. A complementary experiment with acid additions (0, 0.66, 2.65, 4.63, and 7.28 mol H+ m−2 yr−1) was also carried out to examine the direct impact of acidification. We found that N enrichment significantly increased plant productivity but decreased soil microbial respiration. While the increased productivity was associated with increased N availability, the reduction in soil microbial respiration was mainly explained by the decreased soil pH. In the acid addition experiment, enhanced soil acidity due to the increased proton concentration significantly reduced soil microbial respiration. These results indicate that N-induced changes in soil pH represent an important mechanism driving the ecosystem functions, suggesting that N-induced acidification should receive more attention for understanding and predicting ecosystem services under future N-enrichment scenarios.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Yang, Fei and Zhang, Zhilong and Barberan, Albert and Yang, Yi and Hu, Shuijin and Guo, Hui}, year={2021}, month={Feb} }
 @article{zhang_cai_hu_chang_2021, title={Plant mixture effects on carbon-degrading enzymes promote soil organic carbon accumulation}, volume={163}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2021.108457}, abstractNote={Microbial decomposition of soil organic carbon (SOC) is a major determinant of the global climate and terrestrial ecosystem services. Despite the rapid loss of plant species worldwide, it remains unclear how plant species richness impacts SOC decomposition, especially the decomposition of labile vs. recalcitrant SOC. This is partly because of the variable responses of soil C-degrading enzyme activities to plant species richness. Through a global meta-analysis of 490 paired observations of plant mixtures versus monocultures, we show that plant mixtures significantly enhanced soil C-hydrolase (degrades labile C) and C-oxidase (degrades recalcitrant C) activities by 29.4 and 14.9%, respectively. However, in mixtures, C-hydrolase activity marginally (P = 0.051) increased, while C-oxidase activity significantly decreased with plant species richness. In addition, in mixtures, C-hydrolase but not C-oxidase activity significantly increased with plant functional type richness and experimental duration. These plant species richness and functional type effects on C-hydrolase and C-oxidase activities were consistent among diverse terrestrial ecosystems, plant life forms, the presence/absence of legumes, and climate types. Moreover, increases in C-hydrolase but not C-oxidase activity were positively related with increasing microbial biomass C and SOC under plant mixtures, suggesting that faster microbial decomposition and transformation of labile C pools mediate SOC accumulation at higher plant species richness. These results highlight that plant species richness differentially affects labile and recalcitrant C-degrading enzymes, thereby influencing SOC decomposition, dynamics, and accumulation.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Zhang, Baogang and Cai, Yanjiang and Hu, Shuijin and Chang, Scott X.}, year={2021}, month={Dec} }
 @article{wang_li_wei_su_guo_guo_wang_zhang_hu_2021, title={Responses of soil ammonia-oxidizing bacteria and archaea to short-term warming and nitrogen input in a semi-arid grassland on the Loess Plateau}, volume={102}, ISSN={["1778-3615"]}, DOI={10.1016/j.ejsobi.2020.103267}, abstractNote={Ammonia-oxidizing archaea (AOA) and bacteria (AOB) predominantly control ammonia oxidation, the first and rate-limiting step of nitrification, and critically affect plant utilization and the fate of reactive nitrogen (N) input to soil. Both AOA and AOB are often sensitive to environmental changes, but their responses to the concurrent climate warming and N input remain poorly understood, particularly in semi-arid grassland ecosystems where nitrification dominates soil N transformations. We examined the interactive effects of short-term (2-yr) warming and N input (12 g N m−2 y−1) on the abundance and community structure of AOA and AOB in a semi-arid grassland on China's Loess Plateau. Results showed that AOA abundance was significantly higher than AOB in all treatments. N input significantly increased the abundance of AOA and AOB by 32% and 521%, respectively, and induced a significant shift in the AOB community composition. Warming significantly increased the abundance of AOB by 94%, but had no impact on the AOA abundance. Warming (alone or combined with N input) did not significantly affect the community structure of AOA or AOB. These results indicated that AOB was more sensitive to N input and climate warming than AOA in semi-arid Loess grasslands. Our findings suggest that understanding the responses of AOB abundance and composition may be key to predict the N dynamics under future global change scenarios.}, journal={EUROPEAN JOURNAL OF SOIL BIOLOGY}, author={Wang, Fuwei and Li, Zhen and Wei, Yanan and Su, Fanglong and Guo, Hui and Guo, Jiuxin and Wang, Yi and Zhang, Yi and Hu, Shuijin}, year={2021} }
 @article{wang_li_su_guo_wang_guo_zhu_wang_hu_2021, title={Sensitive Groups of Bacteria Dictate Microbial Functional Responses to Short-term Warming and N Input in a Semiarid Grassland}, volume={10}, ISSN={["1435-0629"]}, DOI={10.1007/s10021-021-00719-4}, journal={ECOSYSTEMS}, author={Wang, Fuwei and Li, Zhen and Su, Fanglong and Guo, Hui and Wang, Peng and Guo, Jiuxin and Zhu, Weixing and Wang, Yi and Hu, Shuijin}, year={2021}, month={Oct} }
 @article{ren_cai_rodrigues_wu_wang_chang_wu_zhou_jiang_hu_2021, title={Species patch size at seeding affects the productivity of mixed legume-grass communities}, volume={129}, ISSN={["1873-7331"]}, DOI={10.1016/j.eja.2021.126342}, abstractNote={The impact of inter- and intraspecific neighboring plants on mixed legume-grass communities has rarely been explored in relation to seeded species patch size. In this study, two native perennial species, the legume alfalfa (Medicago sativa L.) and the grass tall fescue (Festuca arundinacea L.), were investigated as monocultures and in mixture. A three-year growth experiment was conducted to investigate the effects of plant-plant competitive interactions on fine-scale seeding patterns: monoculture, three different conspecific patch sizes (1.0, 0.5, and 0.25 m side length of squares) and a control in which the seeds were mixed and scattered (i.e., patches were not formed) as in conventional seeding. The results demonstrated significant differences in the mutual effect intensity in all conspecific patch sizes, indicating the presence of grass-legume interactions on mixed plant communities. Smaller patch sizes resulted in better facilitation by higher neighbor effect intensity when compared with a larger patch size and the conventional mixture. Seedings in the smallest patch size of 0.25 m × 0.25 m showed intra- and interspecific competition and significantly improved aboveground productivity compared with the other patch sizes. We directly quantified the variation of species neighbor effect intensity between grass and legume mixtures among different species patch sizes at seeding. Integrating this knowledge into species interaction models in plant community ecology could greatly enhance our understanding of species coexistence in grasslands as well as provide opportunities for manipulating competition to achieve specific agronomic aims.}, journal={EUROPEAN JOURNAL OF AGRONOMY}, author={Ren, Haiyan and Cai, Anran and Rodrigues, Jorge L. Mazza and Wu, Xinwei and Wang, Lifeng and Chang, Jiechao and Wu, Xiuyang and Zhou, Quanping and Jiang, Yuehua and Hu, Shuijin}, year={2021}, month={Sep} }
 @article{xiao_ran_hu_guo_2021, title={The response of ammonia oxidizing archaea and bacteria in relation to heterotrophs under different carbon and nitrogen amendments in two agricultural soils}, volume={158}, ISSN={["1873-0272"]}, DOI={10.1016/j.apsoil.2020.103812}, abstractNote={Ammonia-oxidizing archaea (AOA) and bacteria (AOB) drive nitrification and therefore critically modulate plant nitrogen (N) utilization, ecosystem N retention and environmental effects of reactive N. Previous studies have shown that abiotic factors (e.g., soil ammonium concentration, pH) can largely control the abundance and composition of ammonia oxidizers. However, whether the biotic factors, such as heterotrophic microbes play a role in impacting AOA and AOB remain unknown. Here, we conducted two experiments to assess the impacts of heterotrophs on AOA and AOB. First, a microcosm experiment was designed to create environments with different competition intensities between heterotrophic microbes and ammonia oxidizers through adding different amounts and ratios of organic C (cellulose) and mineral N [(NH4)2SO4] into two agriculture soils with long-term distinct fertilization histories. Along with the carbon to nitrogen (C/N) ratio gradient, rapid decreases in AOA and AOB abundances occurred accompanied with increased total microbial biomass and activities (respiration), suggesting intense competition between heterotrophic microbes and ammonia oxidizers. Pyrosequencing data revealed that different C/N ratios of substrate had significant impacts on the composition of the AOB but not on AOA communities. Second, to test whether there were inhibitive interactions through metabolic compounds, we examined the effect of water extracts of soils amended with high ratios of cellulose and ammonium sulfate on AOA /AOB abundances. The results showed that the extracts from substrates with C/N ratio of 50 and 100 reduced AOA and AOB abundance significantly, although this negative effect abated over time. Together, our findings indicate that both direct competition and inhibition by microbial metabolites critically affect AOA and AOB communities, providing new insights into the mechanisms that underlie ammonia oxidizer dynamics in agricultural ecosystems.}, journal={APPLIED SOIL ECOLOGY}, author={Xiao, Rui and Ran, Wei and Hu, Shuijin and Guo, Hui}, year={2021}, month={Feb} }
 @article{qiu_guo_xu_zhang_zhang_chen_zhao_burkey_shew_zobel_et al._2021, title={Warming and elevated ozone induce tradeoffs between fine roots and mycorrhizal fungi and stimulate organic carbon decomposition}, volume={7}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.abe9256}, abstractNote={Warming and elevated ozone alter root traits and mycorrhizal fungal community and stimulate organic carbon decomposition.}, number={28}, journal={SCIENCE ADVANCES}, author={Qiu, Yunpeng and Guo, Lijin and Xu, Xinyu and Zhang, Lin and Zhang, Kangcheng and Chen, Mengfei and Zhao, Yexin and Burkey, Kent O. and Shew, H. David and Zobel, Richard W. and et al.}, year={2021}, month={Jul} }
 @article{yan_diez_huang_li_luo_xu_su_jiang_guo_hu_2020, title={Beyond resource limitation: an expanded test of the niche dimension hypothesis for multiple types of niche axes}, volume={193}, ISSN={["1432-1939"]}, DOI={10.1007/s00442-020-04713-w}, abstractNote={The niche dimension hypothesis predicts that more species can coexist given a greater number of niche axes along which they partition the environment. Although this hypothesis has been broadly supported by nutrient enrichment experiments, its applicability to other ecological factors, such as natural enemies and abiotic stresses, has not been vigorously tested. Here, we examined the generality of the niche dimension hypothesis by experimentally manipulating both resource and non-resource niche dimensions-nitrogen limitation, pathogens and low-temperature stress-in a Tibetan alpine meadow. We found that decreases in niche dimensions led to a significant reduction in species richness, consistent with results from nutrient addition studies. However, different niche variables uniquely affected the plant communities. While nitrogen had largest effects on both community biomass and species richness, pathogens and low-temperature stress, in combination with nitrogen, had synergistic effects on them. Our results provide direct evidence demonstrating that both resource and non-resource niche dimensions can influence species coexistence. These findings suggest that other non-resource factors need to be taken into consideration to better predict the community assembly and control over biodiversity, particularly under the future multifaceted global change scenarios.}, number={3}, journal={OECOLOGIA}, author={Yan, Xuebin and Diez, Jeffrey and Huang, Kailing and Li, Shaopeng and Luo, Xi and Xu, Xinyu and Su, Fanglong and Jiang, Lin and Guo, Hui and Hu, Shuijin}, year={2020}, month={Jul}, pages={689–699} }
 @article{xiao_qiu_tao_zhang_chen_reberg-horton_shi_shew_zhang_hu_2020, title={Biological controls over the abundances of terrestrial ammonia oxidizers}, volume={29}, ISSN={["1466-8238"]}, DOI={10.1111/geb.13030}, abstractNote={Abstract}, number={2}, journal={GLOBAL ECOLOGY AND BIOGEOGRAPHY}, author={Xiao, Rui and Qiu, Yunpeng and Tao, Jinjin and Zhang, Xuelin and Chen, Huaihai and Reberg-Horton, S. Chris and Shi, Wei and Shew, H. David and Zhang, Yi and Hu, Shuijin}, year={2020}, month={Feb}, pages={384–399} }
 @article{long_zhang_liu_zhou_su_xiao_wang_guo_hu_2020, title={Can the scaling of plant nitrogen to phosphorus be altered by global change? An empirical test}, volume={13}, ISSN={["1752-993X"]}, DOI={10.1093/jpe/rtaa032}, abstractNote={Abstract}, number={4}, journal={JOURNAL OF PLANT ECOLOGY}, author={Long, Min and Zhang, Juanjuan and Liu, Zhengyi and Zhou, Luyao and Su, Fanglong and Xiao, Rui and Wang, Yi and Guo, Hui and Hu, Shuijin}, year={2020}, month={Aug}, pages={442–449} }
 @article{fowler_denning_hu_watson_schmidt_2020, title={Carbon Neutral: The Failure of Dung Beetles (Coleoptera: Scarabaeidae) to Affect Dung-Generated Greenhouse Gases in the Pasture}, volume={49}, ISSN={["1938-2936"]}, DOI={10.1093/ee/nvaa094}, abstractNote={Abstract}, number={5}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Fowler, Fallon and Denning, Steve and Hu, Shuijin and Watson, Wes and Schmidt, Jason}, year={2020}, month={Oct}, pages={1105–1116} }
 @article{zhang_zhang_yin_yang_zhao_jiang_tao_yan_qiu_guo_et al._2020, title={Combination of warming and N inputs increases the temperature sensitivity of soil N2O emission in a Tibetan alpine meadow}, volume={704}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2019.135450}, abstractNote={Many high-elevation alpine ecosystems have been experiencing significant increases in air temperature and, to a lesser extent, nitrogen (N) deposition. These changes may affect N-cycling microbes and enhance emissions of nitrous oxide (N2O, a potent greenhouse gas) from soil. However, few studies have investigated whether and how the resulting changes in N-cycling microbes may affect the temperature sensitivity (Q10) of N2O emission and in turn feed back to N2O emissions. We conducted two incubation experiments to examine N2O emissions and their temperature sensitivities in soils that had experienced 3-yr field treatments of warming, N inputs and their combination in a Tibetan alpine meadow. Our results showed that neither N inputs nor warming alone affected the rate or Q10 of soil N2O emission, but combining the two significantly increased both parameters. Also, combined N and warming significantly increased the abundance of ammonia-oxidizing bacteria (AOB), corresponding with high soil N2O emission. In addition, N2O emission from nitrification accounted for 60-80% of total emissions in all soils, indicating that nitrifying microbes dominated the N2O production and its temperature sensitivity. Using random forest (RF) and structural equation model (SEM) analyses, we further evaluated the effects of various soil characteristics on soil N2O emissions and Q10. We identified soil moisture, pH, N mineralization and AOB abundance as the main predictors of the Q10 of N2O emissions. Together, these findings suggest that alterations in soil moisture, pH and ammonia-oxidizing bacteria induced by long-term N inputs and warming may increase temperature sensitivity of soil N2O emissions, leading to a positive climate feedback in this high-altitude alpine ecosystem.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Zhang, Yi and Zhang, Nan and Yin, Jingjing and Yang, Fei and Zhao, Yexin and Jiang, Zhongquan and Tao, Jinjin and Yan, Xuebin and Qiu, Yunpeng and Guo, Hui and et al.}, year={2020}, month={Feb} }
 @article{jiang_jiang_zhang_su_tian_wang_sun_nong_hu_wang_et al._2020, title={Contrasting the Pb (II) and Cd (II) tolerance of Enterobacter sp. via its cellular stress responses}, volume={22}, ISSN={["1462-2920"]}, DOI={10.1111/1462-2920.14719}, abstractNote={Summary}, number={4}, journal={ENVIRONMENTAL MICROBIOLOGY}, author={Jiang, Zhongquan and Jiang, Liu and Zhang, Lin and Su, Mu and Tian, Da and Wang, Tong and Sun, Yalin and Nong, Ying and Hu, Shuijin and Wang, Shimei and et al.}, year={2020}, month={Apr}, pages={1507–1516} }
 @article{wang_huang_hu_2020, title={Distinct fine-root responses to precipitation changes in herbaceous and woody plants: a meta-analysis}, volume={225}, ISSN={["1469-8137"]}, DOI={10.1111/nph.16266}, abstractNote={Summary}, number={4}, journal={NEW PHYTOLOGIST}, author={Wang, Peng and Huang, Kailing and Hu, Shuijin}, year={2020}, month={Feb}, pages={1491–1499} }
 @article{wu_wu_saleem_wang_hu_bai_pan_chen_2020, title={Ecological clusters based on responses of soil microbial phylotypes to precipitation explain ecosystem functions}, volume={142}, ISSN={["1879-3428"]}, DOI={10.1016/j.soilbio.2020.107717}, abstractNote={Ecological classification has been proposed as a way to more tightly link microbial communities and ecosystem functions, but few studies have attempted to relate ecological classifications of microbial communities with specific ecosystem functions. Here, we conducted a 3-year experiment with nine levels of artificial precipitation (100–500 mm) in a typical semi-arid steppe. The first five levels (≤300 mm) were considered a “dry” gradient, and the last five (≥300 mm) were considered a “wet” gradient. Increases in precipitation under dry and wet gradients did not alter the alpha diversities of soil bacterial, soil fungal, or plant communities, except that increases in precipitation under the dry gradient decreased bacterial alpha diversity. Increases in precipitation under the dry and wet gradients altered the composition of the soil bacterial community but did not alter the composition of the fungal or plant communities. Ecological clusters (ECs) based on the relationships between the relative abundance of phylotypes and dry and wet gradients were correlated with soil C or N mineralization rates; these ECs explained 14–28% of the total variance in soil C and N mineralization rates. In contrast, soil C or N mineralization rates were not correlated with the commonly measured properties (e.g., biomass and diversity) of plant, soil bacterial, and soil fungal communities. Our findings indicate that the grouping of soil microorganisms into ECs based on responses to precipitation gradients can provide insights into the relationships between soil organisms and ecosystem functions.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Wu, Ying and Wu, Jianping and Saleem, Muhammad and Wang, Bing and Hu, Shuijin and Bai, Yongfei and Pan, Qingmin and Chen, Dima}, year={2020}, month={Mar} }
 @article{wang_wu_chen_wu_hu_li_bai_2020, title={Grazing simplifies soil micro-food webs and decouples their relationships with ecosystem functions in grasslands}, volume={26}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.14841}, abstractNote={Abstract}, number={2}, journal={GLOBAL CHANGE BIOLOGY}, author={Wang, Bing and Wu, Liji and Chen, Dima and Wu, Ying and Hu, Shuijin and Li, Linghao and Bai, Yongfei}, year={2020}, month={Feb}, pages={960–970} }
 @article{zhao_guo_shu_wang_hu_2020, title={Impacts of drought and nitrogen enrichment on leaf nutrient resorption and root nutrient allocation in four Tibetan plant species}, volume={723}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2020.138106}, abstractNote={Plant nutrient resorption, a process by which plant withdraws nutrients from senescing structures to developing tissues, can significantly affect plant growth, litter decomposition and nutrient cycling. Global change factors, such as nitrogen (N) deposition and altered precipitation, may mediate plant nutrient resorption and allocation. The ongoing global change is accompanied with increased N inputs and drought frequency in many regions. However, the interactive effects of increased N availability and drought on plant nutrient-responses remain largely unclear. In a pot experiment, we examined the impacts of N enrichment and drought on leaf N and phosphorous (P) resorption and root nutrient allocation in four species from the Qinghai-Tibet Plateau, including two graminoid species (Kobresia capillifolia and Elymus nutans) and two forb species (Delphinium kamaonense and Aster diplostephioides). Our results showed divergent resorption patterns within the two functional groups. E. nutans and D. kamaonense showed stronger N resorption than K. capillifolia and A. diplostephioides. N addition did not alter their N resorption efficiencies, but decreased the N resorption proficiencies of the former two species. In contrast, drought did not affect N or P resorption proficiencies, but decreased N resorption efficiency of K. capillifolia. Besides, N addition facilitated P resorption in K. capillifolia and D. kamaonense, and drought did the same in A. diplostephioides, suggesting that P resorption plays an important role in nutrient conservation in these species. Moreover, species with stronger N resorption allocated more biomass C or N to aboveground and enhanced their litter quality under N enrichment, while species with weaker resorption allocated more biomass C and/or N to belowground part under drought. Together, these results show that the responses of nutrient resorption and allocation to N enrichment and drought are highly species-specific. Future studies should take these differential responses into consideration to better predict litter decomposition and ecosystem nutrient cycling.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Zhao, Qingzhou and Guo, Jin and Shu, Meng and Wang, Peng and Hu, Shuijin}, year={2020}, month={Jun} }
 @article{bai_wang_hall_wang_ye_li_li_zhou_qiu_guo_et al._2020, title={Interactive global change factors mitigate soil aggregation and carbon change in a semi-arid grassland}, volume={26}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.15220}, abstractNote={Abstract}, number={9}, journal={GLOBAL CHANGE BIOLOGY}, author={Bai, Tongshuo and Wang, Peng and Hall, Steven J. and Wang, Fuwei and Ye, Chenglong and Li, Zhen and Li, Shijie and Zhou, Luyao and Qiu, Yunpeng and Guo, Jiuxin and et al.}, year={2020}, month={Sep}, pages={5320–5332} }
 @article{xu_zhang_zhu_xiao_zhu_zhang_yu_li_zhu_tu_et al._2020, title={Large losses of ammonium-nitrogen from a rice ecosystem under elevated CO2}, volume={6}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.abb7433}, abstractNote={Carbon dioxide enrichment facilitates nitrogen loss through anaerobic oxidation of ammonium coupled to the reduction of iron.}, number={42}, journal={SCIENCE ADVANCES}, author={Xu, Chenchao and Zhang, Kaihang and Zhu, Wanying and Xiao, Jing and Zhu, Chen and Zhang, Naifang and Yu, Fangjian and Li, Shuyao and Zhu, Chunwu and Tu, Qichao and et al.}, year={2020}, month={Oct} }
 @article{li_wang_chen_liu_zhou_deng_dong_bao_bai_li_et al._2020, title={Mowing alters nitrogen effects on the community-level plant stoichiometry through shifting plant functional groups in a semi-arid grassland}, volume={15}, ISSN={["1748-9326"]}, DOI={10.1088/1748-9326/ab8a87}, abstractNote={Abstract}, number={7}, journal={ENVIRONMENTAL RESEARCH LETTERS}, author={Li, Shijie and Wang, Fuwei and Chen, Mengfei and Liu, Zhengyi and Zhou, Luyao and Deng, Jun and Dong, Changjun and Bao, Guocheng and Bai, Tongshuo and Li, Zhen and et al.}, year={2020}, month={Jul} }
 @article{yang_zhou_weih_li_zhai_zhang_chen_liu_liu_hu_2020, title={Mycorrhizal nitrogen uptake of wheat is increased by earthworm activity only under no-till and straw removal conditions}, volume={155}, ISSN={["1873-0272"]}, DOI={10.1016/j.apsoil.2020.103672}, abstractNote={A large part of crop nutrient uptake occurs through the interaction of roots with symbiotic arbuscular mycorrhizal fungi (AMF). However, it is still an open question how straw management and earthworm activity affect AMF community structure and their nitrogen-transferring function in wheat. A split-plot field experiment was conducted to address this question. Three straw management regimes including different tillage treatments (no-till with no straw, NTNS; rotary tillage with straw return, RTSR and ditch-buried straw return, DBSR), and two earthworm treatments (no earthworm, −E; and earthworm addition, +E) were conducted. The AMF community structure in the wheat roots was characterized with high-throughput sequencing, and its function in terms of N acquisition was measured with 15N isotope tracing through hyphal in-growth cores. Our results showed that both the DBSR and RTSR treatments significantly changed AMF community composition and enhanced the mycorrhiza-mediated plant N uptake when compared to NTNS. The effect of earthworm activity on AMF community composition and mycorrhiza-mediated N uptake strongly depended on the straw management regimes. While earthworm presence increased AMF dominance (+32.9%) and mycorrhizal N uptake (+2.05-fold) under straw removal, they decreased AMF dominance (−30.4% and −41.9% respectively) and mycorrhizal N uptake (−37.3% and −34.3% respectively) under both DBSR and RTSR treatments in comparison with the absence of earthworms. It is concluded that straw addition shifts the AMF community structure and increases N uptake by the host plants; and that the effect of earthworms on AMF community structure and functioning depends on the straw management regime. The results suggest that straw management and its interaction with earthworms can affect mycorrhiza-mediated plant N uptake, possibly through altering some dominant AMF taxa.}, journal={APPLIED SOIL ECOLOGY}, author={Yang, Haishui and Zhou, Jiajia and Weih, Martin and Li, Yifan and Zhai, Silong and Zhang, Qian and Chen, Weiping and Liu, Jian and Liu, Ling and Hu, Shuijin}, year={2020}, month={Nov} }
 @misc{cheng_wang_wang_wang_chang_cai_zhang_niu_hu_2020, title={Nitrogen deposition differentially affects soil gross nitrogen transformations in organic and mineral horizons}, volume={201}, ISSN={["1872-6828"]}, DOI={10.1016/j.earscirev.2019.103033}, abstractNote={Reactive nitrogen (N) input can profoundly alter soil N transformations and long-term productivity of forest ecosystems. However, critical knowledge gaps exist in our understanding of N deposition effects on internal soil N cycling in forest ecosystems. It is well established that N addition enhances soil N availability based on traditional net mineralization rate assays. Yet, experimental additions of inorganic N to soils broadly show a suppression of microbial activity and protein depolymerization. Here we show, from a global meta-analysis of 15N-labelled studies that gross N transformation rates in forest soil organic and mineral horizons differentially respond to N addition. In carbon (C)-rich organic horizons, N addition significantly enhanced soil gross rates of N mineralization, nitrification and microbial NO3¯ immobilization rates, but decreased gross microbial NH4+ immobilization rates. In C-poor mineral soils, in contrast, N addition did not change gross N transformation rates except for increasing gross nitrification rates. An initial soil C/N threshold of approx. 14.6, above which N addition enhanced gross N mineralization rates, could explain why gross N mineralization was increased by N deposition in organic horizons alone. Enhancement of gross N mineralization by N deposition was also largely attributed to enhanced N mineralization activity per unit microbial biomass. Our results indicate that the net effect of N input on forest soil gross N transformations are highly stratified by soil C distribution along the soil profile, and thus challenge the perception that N availability ubiquitously limits N mineralization. These findings suggest that these differences should be integrated into models to better predict forest ecosystem N cycle and C sequestration potential under future N deposition scenarios.}, journal={EARTH-SCIENCE REVIEWS}, author={Cheng, Yi and Wang, Jing and Wang, Jinyang and Wang, Shenqiang and Chang, Scott X. and Cai, Zucong and Zhang, Jinbo and Niu, Shuli and Hu, Shuijin}, year={2020}, month={Feb} }
 @article{pan_wang_qiu_chen_zhang_ye_guo_zhu_chen_xu_et al._2020, title={Nitrogen-induced acidification, not N-nutrient, dominates suppressive N effects on arbuscular mycorrhizal fungi}, volume={26}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.15311}, abstractNote={Abstract}, number={11}, journal={GLOBAL CHANGE BIOLOGY}, author={Pan, Shang and Wang, Yang and Qiu, Yunpeng and Chen, Dima and Zhang, Lin and Ye, Chenglong and Guo, Hui and Zhu, Weixing and Chen, Aiqun and Xu, Guohua and et al.}, year={2020}, month={Nov}, pages={6568–6580} }
 @article{su_wang_li_wei_li_bai_wang_guo_hu_2020, title={Predominant role of soil moisture in regulating the response of ecosystem carbon fluxes to global change factors in a semi-arid grassland on the Loess Plateau}, volume={738}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2020.139746}, abstractNote={Climate warming, altered precipitation and nitrogen deposition may critically affect plant growth and ecosystem carbon fluxes. However, the underlying mechanisms are not fully understood. We conducted a 2-yr, multi-factor experiment (warming (W), altered precipitation (+30% and − 30%) and nitrogen addition (N)) in a semi-arid grassland on the Loess Plateau to study how these factors affect ecosystem carbon fluxes. Surprisingly, no interactive effects of warming, altered precipitation and nitrogen addition were detected on parameters of ecosystem carbon fluxes, including net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), gross ecosystem productivity (GEP) and soil respiration (SR). Warming marginally reduced NEE and GEP mainly due to its negative effects on them in July and August. Altered precipitation significantly affected all parameters of carbon fluxes with precipitation reduction decreasing NEE, ER and GEP, whereas precipitation addition increasing SR. In contrast, nitrogen addition had little effect on any parameters of carbon fluxes. Soil moisture was the most important driver and positively correlated with ecosystem carbon fluxes and warming impacted ecosystem carbon fluxes indirectly by decreasing soil moisture. While plant community cover did not show significant association with carbon fluxes, semi-shrubs cover was positively related to NEE, ER and GEP. Together, these results suggest that soil water availability, rather than soil temperature and nitrogen availability, may dominate the effect of the future multi-faceted global changes on semi-arid grassland carbon fluxes on the Loess Plateau.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Su, Fanglong and Wang, Fuwei and Li, Zhen and Wei, Yanan and Li, Shijie and Bai, Tongshuo and Wang, Yi and Guo, Hui and Hu, Shuijin}, year={2020}, month={Oct} }
 @article{zhang_zhang_yin_zhao_yang_jiang_tao_yan_qiu_guo_et al._2020, title={Simulated warming enhances the responses of microbial N transformations to reactive N input in a Tibetan alpine meadow}, volume={141}, ISSN={["1873-6750"]}, DOI={10.1016/j.envint.2020.105795}, abstractNote={Alpine ecosystems worldwide are characterized with high soil organic carbon (C) and low mineral nitrogen (N). Climate warming has been predicted to stimulate microbial decomposition and N mineralization in these systems. However, experimental results are highly variable, and the underlying mechanisms remain unclear. We examined the effects of warming, N input, and their combination on soil N pools and N-cycling microbes in a field manipulation experiment. Special attention was directed to the ammonia-oxidizing bacteria and archaea, and their mediated N-cycling processes (transformation rates and N2O emissions) in the third plant growing season after the treatments were initiated. Nitrogen input (12 g m−2 y−1) alone significantly increased soil mineral N pools and plant N uptake, and stimulated the growth of AOB and N2O emissions in the late growing season. While warming (by 1.4 °C air temperature) alone did not have significant effects on most parameters, it amplified the effects of N input on soil N concentrations and AOB abundance, eliciting a chain reaction that increased nitrification potential (+83%), soil NO3−-N (+200%), and N2O emissions (+412%) across the whole season. Also, N input reduced AOB diversity but increased the dominance of genus Nitrosospira within the AOB community, corresponding to the increased N2O emissions. These results showed that a small temperature increase in soil may significantly enhance N losses through NO3− leaching and N2O emissions when mineral N becomes available. These findings suggest that interactions among global change factors may predominantly affect ammonia-oxidizing microbes and their mediated N-cycling processes in alpine ecosystems under future climate change scenarios.}, journal={ENVIRONMENT INTERNATIONAL}, author={Zhang, Yi and Zhang, Nan and Yin, Jingjing and Zhao, Yexin and Yang, Fei and Jiang, Zhongquan and Tao, Jinjin and Yan, Xuebin and Qiu, Yunpeng and Guo, Hui and et al.}, year={2020}, month={Aug} }
 @article{wang_guo_xu_yan_zhang_qiu_zhao_huang_luo_yang_et al._2020, title={Soil acidification alters root morphology, increases root biomass but reduces root decomposition in an alpine grassland}, volume={265}, ISSN={["1873-6424"]}, DOI={10.1016/j.envpol.2020.115016}, abstractNote={Soil acidification has been expanding in many areas of Asia due to increasing reactive nitrogen (N) inputs and industrial activities. While the detrimental effects of acidification on forests have been extensively studied, less attention has been paid to grasslands, particularly alpine grasslands. In a soil pH manipulation experiment in the Qinghai-Tibet Plateau, we examined the effects of soil acidification on plant roots, which account for the major part of alpine plants. After three years of manipulation, soil pH decreased from 6.0 to 4.7 with the acid-addition gradient, accompanied by significant changes in the availability of soil nitrogen, phosphorus and cations. Plant composition shifted with the soil acidity, with graminoids replacing forbs. Differing from findings in forests, soil acidification in the alpine grassland increased root biomass by increasing the fraction of coarse roots and the production of fine roots, corresponding to enhanced sedge and grass biomass, respectively. In addition, litter decomposability decreased with altered root morphological and chemical traits, and soil acidification slowed root decomposition by reducing soil microbial activity and litter quality. Our results showed that acidification effect on root dynamics in our alpine grassland was significantly different from that in forests, and supported similar results obtained in limited studies in other grassland ecosystems. These results suggest an important role of root morphology in mediating root dynamics, and imply that soil acidification may lead to transient increase in soil carbon stock as root standing biomass and undecomposed root litter. These changes may reduce nutrient cycling and further constrain ecosystem productivity in nutrient-limiting alpine systems.}, journal={ENVIRONMENTAL POLLUTION}, author={Wang, Peng and Guo, Jin and Xu, Xinyu and Yan, Xuebin and Zhang, Kangcheng and Qiu, Yunpeng and Zhao, Qingzhou and Huang, Kailing and Luo, Xi and Yang, Fei and et al.}, year={2020}, month={Oct} }
 @article{xiao_wang_lu_chen_wu_zhu_hu_bai_2020, title={Soil acidification reduces the effects of short-term nutrient enrichment on plant and soil biota and their interactions in grasslands}, volume={26}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.15167}, abstractNote={Abstract}, number={8}, journal={GLOBAL CHANGE BIOLOGY}, author={Xiao, Hong and Wang, Bing and Lu, Shunbao and Chen, Dima and Wu, Ying and Zhu, Yuhe and Hu, Shuijin and Bai, Yongfei}, year={2020}, month={Aug}, pages={4626–4637} }
 @article{tian_jiang_jiang_su_feng_zhang_wang_li_hu_2019, title={A new insight into lead (II) tolerance of environmental fungi based on a study of Aspergillus niger and Penicillium oxalicum}, volume={21}, ISSN={["1462-2920"]}, DOI={10.1111/1462-2920.14478}, abstractNote={Summary}, number={1}, journal={ENVIRONMENTAL MICROBIOLOGY}, author={Tian, Da and Jiang, Zhongquan and Jiang, Liu and Su, Mu and Feng, Zheye and Zhang, Lin and Wang, Shimei and Li, Zhen and Hu, Shuijin}, year={2019}, month={Jan}, pages={471–479} }
 @article{ye_hall_hu_2019, title={Controls on mineral-associated organic matter formation in a degraded Oxisol}, volume={338}, ISSN={["1872-6259"]}, DOI={10.1016/j.geoderma.2018.12.011}, abstractNote={Oxisols are the dominant soil type in humid tropical and subtropical regions and are subjected to both drying–rewetting (DRW) cycles and fluctuating oxygen (O2) availability driven by warm temperatures and abundant rainfall in surface layers. Drying-rewetting cycles and O2 fluctuations may critically affect the microbial transformation of plant litter and subsequent stabilization as mineral-associated organic carbon (MAOC), but experimental data are still limited. We examined the impacts of DRW cycles, and variable O2 regimes with constant moisture, on carbon (C) and iron (Fe) dynamics in a degraded Oxisol (under long-term fallow) with added plant residues. In laboratory incubations (>3 months), both DRW cycling and fluctuating O2 availability induced a flush of respiration and a temporary increase in microbial biomass C (MBC) following soil rewetting or O2 exposure, although MBC was consistently suppressed in these treatments relative to the control (60% water holding capacity under constantly aerobic condition). Consequently, DRW cycles significantly increased but O2 fluctuations significantly decreased cumulative C mineralization relative to the control. Concentrations of short-range-ordered Fe oxides peaked immediately after litter addition and decreased five-fold during the remainder of the experiment. Mineral-associated C (defined as the chemically dispersed <53 μm soil fraction) increased 42–64% relative to initial values but was significantly lower under DRW cycling and fluctuating O2 relative to the control. Correspondingly, these treatments had greater fine particulate organic C (53–250 μm), despite increased CO2 production under DRW cycling. Our data indicate the potential for rapid and significant accrual of MAOC in a degraded Oxisol, but environmental factors such as DRW cycling and fluctuating O2 can inhibit the conversion of plant litter to MAOC—possibly by suppressing microbial biomass formation and/or microbial transformations of organic matter.}, journal={GEODERMA}, author={Ye, Chenglong and Hall, Steven J. and Hu, Shuijin}, year={2019}, month={Mar}, pages={383–392} }
 @article{yang_niu_collins_yan_ji_ling_zhou_du_guo_hu_2019, title={Cover Image}, volume={30}, ISSN={1085-3278}, url={http://dx.doi.org/10.1002/LDR.3244}, DOI={10.1002/LDR.3244}, abstractNote={The cover image is based on the Research Article Grazing practices affect the soil microbial community composition in a Tibetan alpine meadow, by Fei Yang et al., https://doi.org/10.1002/ldr.3189.}, number={1}, journal={Land Degradation & Development}, publisher={Wiley}, author={Yang, Fei and Niu, Kechang and Collins, Courtney G. and Yan, Xuebin and Ji, Yangguang and Ling, Ning and Zhou, Xianhui and Du, Guozhen and Guo, Hui and Hu, Shuijin}, year={2019}, month={Jan}, pages={i-i} }
 @article{bai_tao_li_shu_yan_wang_ye_guo_wang_hu_2019, title={Different microbial responses in top- and sub-soils to elevated temperature and substrate addition in a semiarid grassland on the Loess Plateau}, volume={70}, ISSN={["1365-2389"]}, DOI={10.1111/ejss.12800}, abstractNote={The Loess Plateau soil in northwest China originated from wind sediments and is characterized by deep soil profiles and large organic carbon (C) content. Severe soil erosion constantly exposes deep soils to the surface, making the organic C vulnerable to microbial decomposition. Few, however, have so far examined how soil microbial activity and community composition in the deep loess soil respond to perturbations. We examined microbial responses in three layers of a clay‐loam loess (topsoil, 0–20 cm; midsoil, 40–60 cm; subsoil, 80–100 cm) to substrate additions (0.8 g glucose‐C kg−1 soil) under two temperature regimes (25 and 35°C). Soil C:N ratio was significantly larger in the subsoil (20.3) than topsoil (7.4). Glucose addition significantly increased CO2 efflux during a 30‐day incubation period and the relative magnitude of the increase was four times larger in the subsoil than topsoil. The temperature sensitivity (Q10) of soil CO2 efflux increased significantly with soil depth in the absence of glucose addition (i.e., ambient soil), but it decreased under glucose addition. Also, glucose addition significantly increased phenol oxidase and peroxidase activities in the subsoil, which might contribute to the stimulation of microbial CO2 efflux. Composition of the microbial community was more affected by temperature increase in the topsoil, but more responsive to labile C addition in the subsoil. Together, these results indicated that the composition of soil communities and microbial activities in the topsoil and deep soil responded differently to warming and labile C input. Our findings suggest that organic C in deep loess soils can be highly sensitive to environmental changes, emphasizing the need for more long‐term monitoring and quantitative assessment of organic C release from this important C pool.}, number={5}, journal={EUROPEAN JOURNAL OF SOIL SCIENCE}, author={Bai, Tongshuo and Tao, Jinjin and Li, Zhen and Shu, Meng and Yan, Xuebin and Wang, Peng and Ye, Chenglong and Guo, Hui and Wang, Yi and Hu, Shuijin}, year={2019}, month={Sep}, pages={1025–1036} }
 @article{xu_wolfe_diez_zheng_guo_hu_2019, title={Differential germination strategies of native and introduced populations of the invasive species Plantago virginica}, ISSN={["1314-2488"]}, DOI={10.3897/neobiota.43.30392}, abstractNote={Germination strategies are critically important for the survival, establishment and spread of plant species. Although many plant traits related to invasiveness have been broadly studied, the earliest part of the life cycle, germination, has received relatively little attention. Here, we compared the germination patterns between native (North America) and introduced (China) populations of Plantagovirginica for four consecutive years to examine whether there has been adaptive differentiation in germination traits and how these traits are related to local climatic conditions. We found that the introduced populations of P.virginica had significantly higher germination percentages and faster and shorter durations of germination than native populations. Critically, the native populations had a significantly larger proportion of seeds that stayed dormant in all four years, with only 60% of seeds germinating in year 1 (compared to >95% in introduced populations). These results demonstrate striking differences in germination strategies between native and introduced populations which may contribute to their successful invasion. Moreover, the germination strategy of P.virginica in their native range exhibited clear geographical variation across populations, with trends towards higher germination percentages at higher latitudes and lower annual mean temperatures and annual precipitation. In the introduced range, however, their germination strategies were more conserved, with less variation amongst populations, suggesting that P.virginica may have experienced strong selection for earlier life history characteristics. Our findings highlight the need to examine the role of rapid evolution of germination traits in facilitating plant invasion.}, number={43}, journal={NEOBIOTA}, author={Xu, Xinyu and Wolfe, Lorne and Diez, Jeffrey and Zheng, Yi and Guo, Hui and Hu, Shuijin}, year={2019}, month={Mar}, pages={101–118} }
 @article{chen_xing_lan_saleem_wu_hu_bai_2019, title={Direct and indirect effects of nitrogen enrichment on soil organisms and carbon and nitrogen mineralization in a semi-arid grassland}, volume={33}, ISSN={["1365-2435"]}, DOI={10.1111/1365-2435.13226}, abstractNote={Abstract}, number={1}, journal={FUNCTIONAL ECOLOGY}, author={Chen, Dima and Xing, Wen and Lan, Zhichun and Saleem, Muhammad and Wu, Yunqiqige and Hu, Shuijin and Bai, Yongfei}, year={2019}, month={Jan}, pages={175–187} }
 @article{sun_guo_guo_guo_hu_2019, title={Divergent responses of leaf N:P:K stoichiometry to nitrogen fertilization in rice and weeds}, volume={67}, ISSN={["1550-2759"]}, DOI={10.1017/wsc.2019.7}, abstractNote={Abstract}, number={3}, journal={WEED SCIENCE}, author={Sun, Xiao and Guo, Jiuxin and Guo, Shiwei and Guo, Hui and Hu, Shuijin}, year={2019}, month={May}, pages={339–345} }
 @article{chen_saleem_cheng_mi_chu_tuvshintogtokh_hu_bai_2019, title={Effects of aridity on soil microbial communities and functions across soil depths on the Mongolian Plateau}, volume={33}, ISSN={["1365-2435"]}, DOI={10.1111/1365-2435.13359}, abstractNote={Abstract}, number={8}, journal={FUNCTIONAL ECOLOGY}, author={Chen, Dima and Saleem, Muhammad and Cheng, Junhui and Mi, Jia and Chu, Pengfei and Tuvshintogtokh, Indree and Hu, Shuijin and Bai, Yongfei}, year={2019}, month={Aug}, pages={1561–1571} }
 @article{shu_zhao_li_zhang_wang_hu_2019, title={Effects of global change factors and living roots on root litter decomposition in a Qinghai-Tibet alpine meadow}, volume={9}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-019-53450-5}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Shu, Meng and Zhao, Qingzhou and Li, Zhen and Zhang, Lin and Wang, Peng and Hu, Shuijin}, year={2019}, month={Nov} }
 @article{chen_zhang_tang_su_tian_zhang_li_hu_2019, title={Enhanced Pb immobilization via the combination of biochar and phosphate solubilizing bacteria}, volume={127}, ISSN={["1873-6750"]}, DOI={10.1016/j.envint.2019.03.068}, abstractNote={Application of biochar in heavy metal remediation suffers from lack of long-term stability. Phosphate-solubilizing bacteria (PSB) are able to elevate P release and the subsequent reaction with Pb to form stable pyromorphite. This study investigated the feasibility of applying PSB modified biochar to enhance immobilization of Pb2+. An alkaline biochar produced from rice husk (RB) and a slightly acidic biochar produced from sludge (SB) were selected. It showed that the biochars can effectively remove Pb2+ via adsorption, i.e., aqueous Pb concentrations after RB and SB addition were reduced by 18.61 and 53.89% respectively. The addition of PSB increased the Pb2+ removal for both biochars (to 24.11 and 60.85%, respectively). In particular, PSB significantly enhanced the formation of stable pyromorphite on surface of SB. This is due to that the evenly distributed PSB enhanced P release and regulated pH on the biochar surface. Moreover, small particles (<0.074 mm) showed their higher ability to induce the formation of pyromorphite, for both RB and SB. Nevertheless, SB demonstrated higher capability of sorption, together with its more abundant P content, which provided a more suitable platform to attract PSB to immobilize heavy metals. Therefore, the combination of biochar and PSB is a promising candidate material for heavy metal remediation. However, the types and particle size distribution of biochar should be addressed.}, journal={ENVIRONMENT INTERNATIONAL}, author={Chen, Haoming and Zhang, Jiawen and Tang, Lingyi and Su, Mu and Tian, Da and Zhang, Lin and Li, Zhen and Hu, Shuijin}, year={2019}, month={Jun}, pages={395–401} }
 @article{yang_niu_collins_yan_ji_ling_zhou_du_guo_hu_2019, title={Grazing practices affect the soil microbial community composition in a Tibetan alpine meadow}, volume={30}, ISSN={["1099-145X"]}, DOI={10.1002/ldr.3189}, abstractNote={Abstract}, number={1}, journal={LAND DEGRADATION & DEVELOPMENT}, author={Yang, Fei and Niu, Kechang and Collins, Courtney G. and Yan, Xuebin and Ji, Yangguang and Ling, Ning and Zhou, Xianhui and Du, Guozhen and Guo, Hui and Hu, Shuijin}, year={2019}, month={Jan}, pages={49–59} }
 @article{zhang_hu_han_wu_tian_su_wang_li_hu_2019, title={Influences of multiple clay minerals on the phosphorus transport driven by Aspergillus niger}, volume={177}, ISSN={["1872-9053"]}, DOI={10.1016/j.clay.2019.04.026}, abstractNote={Phosphorus (P) is a major limiting nutrient for plant growth. Clay minerals are able to work as active centers in soil system due to their high surface area and CEC. Yet, effects of clay minerals on P biogeochemical cycle driven by microorganisms are still unclear. In this study, hydroxylapatite and three typical clay minerals (kaolinite, palygorskite, and montmorillonite) were incubated with Aspergillus niger to investigate microbial influences on P release and adsorption. Due to the mineral particles, hyphae wrapped small montmorillonite particles (<10 μm, confirmed by SEM and TEM), which promoted microbial bioactivities, e.g., respiration and acid production. P consumption by the fungus lowered the available P from 143 to 68 ppm. Meanwhile, ATR-IR spectra and HPLC analysis confirmed the intense adsorption of oxalic acid (the primary microbial secretion) onto montmorillonite. Despite the higher acid production, both the high adsorption capability of the clay and the acid consumed by phosphate dissolution caused that pH values increased from ~2 to ~4 after montmorillonite addition. In contrast, low CEC, dispersibility, and surface area of kaolinite and palygorskite limited their ability to enhance microbial activities and the subsequent interactions with hyphae. Therefore, clay minerals, especially montmorillonite, can drive P transport with the favor from fungi in ecosystem.}, journal={APPLIED CLAY SCIENCE}, author={Zhang, Lin and Hu, Yunxiao and Han, Feiyu and Wu, Yiling and Tian, Da and Su, Mu and Wang, Shimei and Li, Zhen and Hu, Shuijin}, year={2019}, month={Sep}, pages={12–18} }
 @misc{zhang_li_wu_hu_2019, title={Invasive plants differentially affect soil biota through litter and rhizosphere pathways: a meta-analysis}, volume={22}, ISSN={["1461-0248"]}, DOI={10.1111/ele.13181}, abstractNote={Abstract}, number={1}, journal={ECOLOGY LETTERS}, author={Zhang, Pei and Li, Bo and Wu, Jihua and Hu, Shuijin}, year={2019}, month={Jan}, pages={200–210} }
 @article{jiang_qian_wang_feng_huang_hungate_kessel_horwath_zhang_qin_et al._2019, title={Limited potential of harvest index improvement to reduce methane emissions from rice paddies}, volume={25}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.14529}, abstractNote={Abstract}, number={2}, journal={GLOBAL CHANGE BIOLOGY}, author={Jiang, Yu and Qian, Haoyu and Wang, Ling and Feng, Jinfei and Huang, Shan and Hungate, Bruce A. and Kessel, Chris and Horwath, William R. and Zhang, Xingyue and Qin, Xiaobo and et al.}, year={2019}, month={Feb}, pages={686–698} }
 @article{guo_tian_wang_han_su_wu_li_hu_2019, title={Reduction of Pb availability during surficial leaching in different types of soils with addition of apatite and oxalic acid}, volume={19}, ISSN={["1614-7480"]}, DOI={10.1007/s11368-018-2100-6}, number={2}, journal={JOURNAL OF SOILS AND SEDIMENTS}, author={Guo, Chenmeng and Tian, Weitao and Wang, Zhijun and Han, Feiyu and Su, Mu and Wu, Yiling and Li, Zhen and Hu, Shuijin}, year={2019}, month={Feb}, pages={741–749} }
 @article{su_wei_wang_guo_zhang_wang_guo_hu_2019, title={Sensitivity of plant species to warming and altered precipitation dominates the community productivity in a semiarid grassland on the Loess Plateau}, volume={9}, ISSN={["2045-7758"]}, DOI={10.1002/ece3.5312}, abstractNote={Abstract}, number={13}, journal={ECOLOGY AND EVOLUTION}, author={Su, Fanglong and Wei, Yanan and Wang, Fuwei and Guo, Jiuxin and Zhang, Juanjuan and Wang, Yi and Guo, Hui and Hu, Shuijin}, year={2019}, month={Jul}, pages={7628–7638} }
 @article{chen_zhang_cao_fu_hu_wu_zhao_liu_2019, title={Stand age and species traits alter the effects of understory removal on litter decomposition and nutrient dynamics in subtropical Eucalyptus plantations}, volume={20}, ISBN={2351-9894}, DOI={10.1016/j.gecco.2019.e00693}, abstractNote={Litter decomposition is a crucial ecological process that regulates nutrient cycling. However, the effects of understory plants and overstory trees on litter decomposition and nutrient dynamics are still poorly understood. We conducted understory plants removal and/or overstory trees removal to examine the resulting effects on litter decomposition and nutrient mineralization in two Eucalyptus plantations with contrasting ages (8-yr-old, 29-yr-old) in subtropical China. Litter bags containing naturally senesced leaves of either overstory Eucalyptus urophylla or understory Dicranopteris dichotoma were placed in field and periodically collected for analyses of carbon (C), nitrogen (N), phosphorus (P) and calculation of mass loss. Our results showed that understory plants removal significantly reduced litter decomposition of E. urophylla in both plantations, but N and P mineralization were reduced only in the 8-yr-old plantation. In contrast, it reduced litter decomposition of D. dichotoma only in the 29-yr-old plantation, but had no effects on N and P mineralization in either plantation. In comparison, overstory tree removal did not have any effects on decomposition or mineralization of N and P of E. urophylla and D. dichotoma litters. These results indicate that the role of understory plants in mediating litter decomposition and nutrient mineralization is more important than overstory trees, and it can be altered by stand age and plant species. Our findings could facilitate the understanding of ecological processes of litter decomposition and nutrient mineralization in subtropical forest ecosystems.}, journal={GLOBAL ECOLOGY AND CONSERVATION}, author={Chen, Yuanqi and Zhang, Yanju and Cao, Jianbo and Fu, Shenglei and Hu, Shuijin and Wu, Jianping and Zhao, Jie and Liu, Zhanfeng}, year={2019}, month={Oct} }
 @article{luo_xu_zheng_guo_hu_2019, title={The role of phenotypic plasticity and rapid adaptation in determining invasion success of Plantago virginica}, volume={21}, ISSN={["1573-1464"]}, DOI={10.1007/s10530-019-02004-x}, number={8}, journal={BIOLOGICAL INVASIONS}, author={Luo, Xi and Xu, Xinyu and Zheng, Yi and Guo, Hui and Hu, Shuijin}, year={2019}, month={Aug}, pages={2679–2692} }
 @article{yang_ma_rong_zeng_wang_hu_ye_zheng_2019, title={Wheat Straw Return Influences Nitrogen-Cycling and Pathogen Associated Soil Microbiota in a Wheat-Soybean Rotation System}, volume={10}, ISSN={["1664-302X"]}, DOI={10.3389/fmicb.2019.01811}, abstractNote={Returning straw to soil is an effective way to sustain or improve soil quality and crop yields. However, a robust understanding of the impact of straw return on the composition of the soil microbial communities under field conditions has remained elusive. In this study, we characterized the effects of wheat straw return on soil bacterial and fungal communities in a wheat–soybean rotation system over a 3-year period, using Illumina-based 16S rRNA, and internal transcribed region (ITS) amplicon sequencing. Wheat straw return significantly affected the α-diversity of the soil bacterial, but not fungal, community. It enhanced the relative abundance of the bacterial phylum Proteobacteria and the fungal phylum Zygomycota, but reduced that of the bacterial phylum Acidobacteria, and the fungal phylum Ascomycota. Notably, it enriched the relative abundance of nitrogen-cycling bacterial genera such as Bradyrhizobium and Rhizobium. Preliminary analysis of soil chemical properties indicated that straw return soils had significantly higher total nitrogen (TN) contents than no straw return soils. In addition, the relative abundance of fungal genera containing pathogens was significantly lower in straw return soils relative to control soils, such as Fusarium, Alternaria, and Myrothecium. These results suggested a selection effect from the 3-year continuous straw return treatment and the soil bacterial and fungal communities were moderately changed.}, journal={FRONTIERS IN MICROBIOLOGY}, author={Yang, Hongjun and Ma, Jiaxin and Rong, Zhenyang and Zeng, Dandan and Wang, Yuanchao and Hu, Shuijin and Ye, Wenwu and Zheng, Xiaobo}, year={2019}, month={Aug} }
 @article{tian_lai_zou_guo_tang_su_li_hu_2018, title={A contrast of lead immobilization via bioapatite under elevated CO2 between acidic and alkaline soils}, volume={34}, ISSN={["1475-2743"]}, DOI={10.1111/sum.12448}, abstractNote={Abstract}, number={4}, journal={SOIL USE AND MANAGEMENT}, author={Tian, D. and Lai, Z. and Zou, X. and Guo, C. and Tang, L. and Su, M. and Li, Z. and Hu, S.}, year={2018}, month={Dec}, pages={542–544} }
 @article{yang_schroeder-moreno_giri_hu_2018, title={Arbuscular Mycorrhizal Fungi and Their Responses to Nutrient Enrichment}, volume={52}, ISBN={["978-3-319-75909-8"]}, ISSN={["1613-3382"]}, DOI={10.1007/978-3-319-75910-4_17}, abstractNote={The roots of most land plants form mycorrhizal associations with soil fungi, in which plants trade carbon for increased nutrient acquisition (e.g., N and P) under nutrient deficiency conditions. However, how nutrient enrichment affects mycorrhiza is still not well understood, in particular under future global changing scenarios such as nitrogen deposition. In this chapter, we first review the major pathways of mycorrhizal-mediated nutrient acquisition and molecular mechanisms of sensing nutrient availability for mycorrhizal fungi and roots. Next, we propose two conceptual models that may control plant C allocation to mycorrhizal fungi in response to nutrient enrichment: reciprocal reward model and root-mycorrhiza trade-off model. We also describe a plant-centric model and fungal-centric model to explain responses of the mycorrhizal fungal community to nutrient enrichment as well as examine impacts of nutrient inputs on mycorrhizas functioning.}, journal={ROOT BIOLOGY}, author={Yang, Haishui and Schroeder-Moreno, Michelle and Giri, Bhoopander and Hu, Shuijin}, year={2018}, pages={429–449} }
 @article{zhang_qiu_cheng_wang_liu_tu_bowman_burkey_bian_zhang_et al._2018, title={Atmospheric CO2 Enrichment and Reactive Nitrogen Inputs Interactively Stimulate Soil Cation Losses and Acidification}, volume={52}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.8b00495}, abstractNote={Reactive N inputs (Nr) may alleviate N-limitation of plant growth and are assumed to help sustain plant responses to the rising atmospheric CO2 (eCO2). However, Nr and eCO2 may elicit a cascade reaction that alters soil chemistry and nutrient availability, shifting the limiting factors of plant growth, particularly in acidic tropical and subtropical croplands with low organic matter and low nutrient cations. Yet, few have so far examined the interactive effects of Nr and eCO2 on the dynamics of soil cation nutrients and soil acidity. We investigated the cation dynamics in the plant-soil system with exposure to eCO2 and different N sources in a subtropical, acidic agricultural soil. eCO2 and Nr, alone and interactively, increased Ca2+ and Mg2+ in soil solutions or leachates in aerobic agroecosystems. eCO2 significantly reduced soil pH, and NH4+-N inputs amplified this effect, suggesting that eCO2-induced plant preference of NH4+-N and plant growth may facilitate soil acidification. This is, to our knowledge, the first direct demonstration of eCO2 enhancement of soil acidity, although other studies have previously shown that eCO2 can increase cation release into soil solutions. Together, these findings provide new insights into the dynamics of cation nutrients and soil acidity under future climatic scenarios, highlighting the urgency for more studies on plant-soil responses to climate change in acidic tropical and subtropical ecosystems.}, number={12}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Zhang, Li and Qiu, Yunpeng and Cheng, Lei and Wang, Yi and Liu, Lingli and Tu, Cong and Bowman, Dan C. and Burkey, Kent O. and Bian, Xinmin and Zhang, Weijian and et al.}, year={2018}, month={Jun}, pages={6895–6902} }
 @article{fang_yu_liu_hu_chapin_2018, title={Climate change, human impacts, and carbon sequestration in China INTRODUCTION}, volume={115}, ISSN={["1091-6490"]}, DOI={10.1073/pnas.1700304115}, abstractNote={The scale of economic growth in China during the past three decades is unprecedented in modern human history. China is now the world’s second largest economic entity, next to the United States. However, this fast economic growth puts China’s environment under increasing stresses. China can be viewed as a massive “laboratory” with complex interactions between socioeconomic and natural systems, providing an excellent opportunity to examine how environmental changes and intensive human economic activities influence natural systems. This special feature explores the impacts of climate change and human activities on the structure and functioning of ecosystems, with emphasis on quantifying the magnitude and distribution of carbon (C) pools and C sequestration in China’s terrestrial ecosystems. We also document how species diversity, species traits, and nitrogen (N) and phosphorus (P) stoichiometry mediate ecosystem C pool and vegetation production. This overview paper introduces the background and scientific significance of the research project, presents the underlying conceptual framework, and summarizes the major findings of each paper.

Reducing CO2 emissions to mitigate regional and global climate change is one of the most challenging issues facing humanity (1). At present, China has the largest annual CO2 emissions in the world ( Upper graph in Fig. 1), placing it in the spotlight of efforts to manage global C emissions and design climate-change policy. It is therefore critical to improve our understanding of the C budget and its dynamics in China to mitigate climate change at both regional and global scales.



Fig. 1. 
Evolution in total national GDP, population, and fossil fuel CO2 emissions, together with trajectory of the national policies in China between 1945 and 2015. ( Upper ) GDP, population, and CO2 emissions. The CO2 emissions data were from Oak Ridge National Laboratory (cdiac.ess-dive.lbl.gov/), and population and GDP data from the World Bank (https://data.worldbank.org/country/). ( Lower ) National … 



[↵][1]1To whom correspondence may be addressed. Email: jyfang{at}urban.pku.edu.cn, fangjingyun{at}ibcas.ac.cn, or terry.chapin{at}alaska.edu.

 [1]: #xref-corresp-1-1}, number={16}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Fang, Jingyun and Yu, Guirui and Liu, Lingli and Hu, Shuijin and Chapin, F. Stuart, III}, year={2018}, month={Apr}, pages={4015–4020} }
 @article{yue_fei-yue_xing-jun_shui-jin_xin_jian-fei_2018, title={Components Analysis of Biochar Based on Near Infrared Spectroscopy Technology}, volume={46}, ISSN={["1872-2040"]}, DOI={10.1016/s1872-2040(17)61081-8}, abstractNote={This study aims to establish a rapid quantitative analysis method for biochar based on near infrared spectroscopy (NIRS) technology. Near infrared spectra of 163 samples in the 10000–3800 cm–1 (1000–2632 nm) range were collected, and the contents of fixed carbon (FC), volatile matter (VM) and ash of samples were also analyzed. A partial least square (PLS) model for FC, VM and Ash was established after the model spectral ranges were optimized, the optimal factors were determined, and the raw spectra were pretreated by multiple scatter correction and second derivative (MSC + SD) method. Finally, the prediction performance of predictive model was evaluated. The results showed that the PLS model had a good prediction ability, and the predicted coefficient R2p of actual values vs prediction values for FC, VM and ash were 0.9423, 0.9517 and 0.9265, respectively. Root mean square error of prediction (RMSEP) was 0.1074, 0.1201 and 0.1243, and ratios of prediction to deviation (RPD) were 3.51, 4.28 and 2.03, respectively. The PLS model had good accuracy and precision for both of FC and VM, and could be used as a quantitative method for FC and VM contents analysis. Nevertheless, PLS model need to improve the precision for Ash analysis according to RPD value. This method provides a fast and effective technical means for the quantitative analysis of biochar components.}, number={4}, journal={CHINESE JOURNAL OF ANALYTICAL CHEMISTRY}, author={Yue, Xie and Fei-Yue, Li and Xing-Jun, Fan and Shui-Jin, Hu and Xin, Xiao and Jian-Fei, Wang}, year={2018}, month={Apr}, pages={609–615} }
 @article{qu_jiang_guo_burkey_zobel_shew_hu_2018, title={Contrasting Warming and Ozone Effects on Denitrifiers Dominate Soil N2O Emissions}, volume={52}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.8b01093}, abstractNote={Nitrous oxide (N2O) in the atmosphere is a major greenhouse gas and reacts with volatile organic compounds to create ozone (an air pollutant) in the troposphere. Climate change factors such as warming and elevated ozone (eO3) affect N2O fluxes, but the direction and magnitude of these effects are uncertain and the underlying mechanisms remain unclear. We examined the impact of simulated warming (control + 3.6 °C) and eO3 (control + 45 ppb) on soil N2O fluxes in a soybean agroecosystem. Results obtained showed that warming significantly increased soil labile C, microbial biomass, and soil N mineralization, but eO3 reduced these parameters. Warming enhanced N2O-producing denitrifers ( nirS- and nirK-type), corresponding to increases in both the rate and sum of N2O emissions. In contrast, eO3 significantly reduced both N2O-producing and N2O-consuming ( nosZ-type) denitrifiers but had no impact on N2O emissions. Further, eO3 offsets the effects of warming on soil labile C, microbial biomass, and the population size of denitrifiers but still increased N2O emissions, indicating a direct effect of temperature on N2O emissions. Together, these findings suggest that warming may promote N2O production through increasing both the abundance and activities of N2O-producing microbes, positively feeding back to the ongoing climate change.}, number={19}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Qu, Yunpeng and Jiang, Yu and Guo, Lijin and Burkey, Kent O. and Zobel, Richard W. and Shew, H. David and Hu, Shuijin}, year={2018}, month={Oct}, pages={10956–10966} }
 @article{li_deng_chen_yang_zheng_dai_zhang_wang_hu_2018, title={Contrasting physical and biochemical properties of orchard soils suppressive and conducive to Fusarium wilt of banana}, volume={34}, ISSN={["1475-2743"]}, DOI={10.1111/sum.12390}, abstractNote={Abstract}, number={1}, journal={SOIL USE AND MANAGEMENT}, author={Li, Z. and Deng, Z. and Chen, S. and Yang, H. and Zheng, Y. and Dai, L. and Zhang, F. and Wang, S. and Hu, Shuijin}, year={2018}, month={Mar}, pages={154–162} }
 @article{zhao_wang_hu_zhang_ouyang_zhang_huang_zhao_wu_xie_et al._2018, title={Economics- and policy-driven organic carbon input enhancement dominates soil organic carbon accumulation in Chinese croplands}, volume={115}, ISSN={["1091-6490"]}, DOI={10.1073/pnas.1700292114}, abstractNote={Significance}, number={16}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Zhao, Yongcun and Wang, Meiyan and Hu, Shuijin and Zhang, Xudong and Ouyang, Zhu and Zhang, Ganlin and Huang, Biao and Zhao, Shiwei and Wu, Jinshui and Xie, Deti and et al.}, year={2018}, month={Apr}, pages={4045–4050} }
 @article{williams_wells_dickey_hu_maul_raskin_reberg-horton_mirsky_2018, title={Establishing the relationship of soil nitrogen immobilization to cereal rye residues in a mulched system}, volume={426}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-018-3566-0}, abstractNote={Soil nitrogen (N) immobilization from cover crop residues may help suppress weeds. We established a gradient of cereal rye shoot biomass to determine the extent that soil N can be immobilized and its effect on redroot pigweed (Amaranthus retroflexus L.). A microplot study was conducted in no-till cereal rye (Secale cereale L.)—soybean (Glycine max L. (Merr.)) systems at two sites in eastern USA. Microplots received 0, 2000, 5000, 8000, 12,000 or 15,000 kg ha−1 of cereal rye shoot biomass, and were injected with two mg 15N kg−1 soil 5 cm below the soil surface. Pigweeds were sown and allowed to germinate. Maximum rates of cereal rye shoot decomposition were observed at ≥5000 kg ha−1. Although cereal rye shoot N declined, shoots became enriched with 15N, indicating fungal transfer of soil N to shoots. Soil inorganic N declined by an average of 5 kg N ha−1. Pigweed tissue N and biomass were reduced in the presence of cereal rye. The magnitude of pigweed N reduction was similar across all shoot application rates. We found weak evidence for a cereal rye shoot-based N immobilization mechanism of weed suppression. Our results indicate N immobilization may be primarily due to root residues.}, number={1-2}, journal={PLANT AND SOIL}, author={Williams, Alwyn and Wells, M. Scott and Dickey, David A. and Hu, Shuijin and Maul, Jude and Raskin, Daniel T. and Reberg-Horton, S. Chris and Mirsky, Steven B.}, year={2018}, month={May}, pages={95–107} }
 @article{ren_taube_stein_zhang_bai_hu_2018, title={Grazing weakens temporal stabilizing effects of diversity in the Eurasian steppe}, volume={8}, ISSN={["2045-7758"]}, DOI={10.1002/ece3.3669}, abstractNote={Abstract}, number={1}, journal={ECOLOGY AND EVOLUTION}, author={Ren, Haiyan and Taube, Friedhelm and Stein, Claudia and Zhang, Yingjun and Bai, Yongfei and Hu, Shuijin}, year={2018}, month={Jan}, pages={231–241} }
 @article{li_su_duan_tian_yang_guo_wang_hu_2018, title={Induced biotransformation of lead (II) by Enterobacter sp in SO4-PO4-Cl-Para solution}, volume={357}, ISSN={["1873-3336"]}, DOI={10.1016/j.jhazmat.2018.06.032}, abstractNote={Pb is a toxic heavy metal in contaminated soil and water, resulted from industrial activities, mine exploration, etc. Phosphate solubilizing bacteria are able to secrete organic acids and further to enhance the solubility of phosphates. Enterobacter. sp and geological fluorapatite (FAp) were applied to investigate the biotransformation of Pb2+ in solution with SO42-, PO43-, and Cl- species by ICP-OES, ATR-IR, XRD, and SEM. Enterobacter. sp can lower pH of the medium to ∼4. Meanwhile, >90% mobile Pb (declining from 1000 to 30 ppm) was immobilized via the combination of Enterobacter. sp and FAp. With the addition of FAp and Pb, pyromorphite was precipitated, but with relatively low content. In contrast, abundant anglesite mineral was formed in such weakly acidic system. These anglesite crystals can even absorb phosphates particles onto their surface. Additionally, geochemical modeling confirms the formation of anglesite and cerussite under weekly acidic and alkalic condition respectively, especially when H2PO4- concentration <10-8 mM. Furthermore, the presence of Cl- in solution leads to the formation of chloropyromorphite when H2PO4- concentration >10-12 mM, especially under neutral environment. This study explored the biotransformation of Pb in SO4-PO4-Cl aqueous system and hence provided guidance on bioremediation of Pb by bacteria and FAp.}, journal={JOURNAL OF HAZARDOUS MATERIALS}, author={Li, Zhen and Su, Mu and Duan, Xiaofang and Tian, Da and Yang, Mengying and Guo, Jieyun and Wang, Shimei and Hu, Shuijin}, year={2018}, month={Sep}, pages={491–497} }
 @article{tang_duan_kong_zhang_zheng_li_mei_zhao_hu_2018, title={Influences of climate change on area variation of Qinghai Lake on Qinghai-Tibetan Plateau since 1980s}, volume={8}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-018-25683-3}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Tang, Lingyi and Duan, Xiaofang and Kong, Fanjin and Zhang, Fan and Zheng, Yangfan and Li, Zhen and Mei, Yi and Zhao, Yanwen and Hu, Shuijin}, year={2018}, month={May} }
 @article{zhang_wang_yuan_xu_tu_fisk_zhang_chen_ritchie_hu_2018, title={Irrigation and weed control alter soil microbiology and nutrient availability in North Carolina Sandhill peach orchards}, volume={615}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2017.09.265}, abstractNote={Orchard management practices such as weed control and irrigation are primarily aimed at maximizing fruit yields and economic profits. However, the impact of these practices on soil fertility and soil microbiology is often overlooked. We conducted a two-factor experimental manipulation of weed control by herbicide and trickle irrigation in a nutrient-poor peach (Prunus persica L. cv. Contender) orchard near Jackson Springs, North Carolina. After three and eight years of treatments, an array of soil fertility parameters were examined, including soil pH, soil N, P and cation nutrients, microbial biomass and respiration, N mineralization, and presence of arbuscular mycorrhizal fungi (AMF). Three general trends emerged: 1) irrigation significantly increased soil microbial biomass and activity, 2) infection rate of mycorrhizal fungi within roots were significantly higher under irrigation than non-irrigation treatments, but no significant difference in the AMF community composition was detected among treatments, 3) weed control through herbicides reduced soil organic matter, microbial biomass and activity, and mineral nutrients, but had no significant impacts on root mycorrhizal infection and AMF communities. Weed-control treatments directly decreased availability of soil nutrients in year 8, especially soil extractable inorganic N. Weed control also appears to have altered the soil nutrients via changes in soil microbes and altered net N mineralization via changes in soil microbial biomass and activity. These results indicate that long-term weed control using herbicides reduces soil fertility through reducing organic C inputs, nutrient retention and soil microbes. Together, these findings highlight the need for alternative practices such as winter legume cover cropping that maintain and/or enhance organic inputs to sustain the soil fertility.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Zhang, Yi and Wang, Liangju and Yuan, Yongge and Xu, Jing and Tu, Cong and Fisk, Connie and Zhang, Weijian and Chen, Xin and Ritchie, David and Hu, Shuijin}, year={2018}, month={Feb}, pages={517–525} }
 @article{ren_eviner_gui_wilson_cobb_yang_zhang_hu_bai_2018, title={Livestock grazing regulates ecosystem multifunctionality in semi-arid grassland}, volume={32}, ISSN={["1365-2435"]}, DOI={10.1111/1365-2435.13215}, abstractNote={Abstract}, number={12}, journal={FUNCTIONAL ECOLOGY}, author={Ren, Haiyan and Eviner, Valerie T. and Gui, Weiyang and Wilson, Gail W. T. and Cobb, Adam B. and Yang, Gaowen and Zhang, Yingjun and Hu, Shuijin and Bai, Yongfei}, year={2018}, month={Dec}, pages={2790–2800} }
 @article{zhang_yan_su_li_wang_wei_ji_yang_zhou_guo_et al._2018, title={Long-term N and P additions alter the scaling of plant nitrogen to phosphorus in a Tibetan alpine meadow}, volume={625}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2017.12.292}, abstractNote={Nitrogen and phosphorus are two important nutrient elements for plants. The current paradigm suggests that the scaling of plant tissue N to P is conserved across environments and plant taxa because these two elements are coupled and coordinately change with each other following a constant allometric trajectory. However, this assumption has not been vigorously examined, particularly in changing N and P environments. We propose that changes in relative availability of N and P in soil alter the N to P relationship in plants. Taking advantage of a 4-yr N and P addition experiment in a Tibetan alpine meadow, we examined changes in plant N and P concentrations of 14 common species. Our results showed that while the scaling of N to P under N additions was similar to the previously reported pattern with a uniform 2/3 slope of the regression between log N and log P, it was significantly different under P additions with a smaller slope. Also, graminoids had different responses from forbs. These results indicate that the relative availability of soil N and P is an important determinant regulating the N and P concentrations in plants. These findings suggest that alterations in the N to P relationships may not only alter plant photosynthate allocation to vegetative or reproductive organs, but also regulate the metabolic and growth rate of plant and promote shifts in plant community composition in a changing nutrient loading environment.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Zhang, Juanjuan and Yan, Xuebin and Su, Fanglong and Li, Zhen and Wang, Ying and Wei, Yanan and Ji, Yangguang and Yang, Yi and Zhou, Xianhui and Guo, Hui and et al.}, year={2018}, month={Jun}, pages={440–448} }
 @article{shen_tian_zhang_tang_su_zhang_li_hu_hou_2018, title={Mechanisms of biochar assisted immobilization of Pb 2+ by bioapatite in aqueous solution}, volume={190}, ISSN={0045-6535}, url={http://dx.doi.org/10.1016/J.CHEMOSPHERE.2017.09.140}, DOI={10.1016/J.CHEMOSPHERE.2017.09.140}, abstractNote={Bioapatite (BAp) is regarded as an effective material to immobilize lead (Pb2+) via the formation of stable pyromorphite. However, when applied in contaminated soil, due to its low surface area and low adsorption capacity, BAp might not sufficiently contact and react with Pb2+. Biochar, a carbon storage material, typically has high surface area and high adsorption capacity. This study investigated the feasibility of using biochar as a reaction platform to enhance BAp immobilization of Pb2+. An alkaline biochar produced from wheat straw pellets (WSP) and a slightly acidic biochar produced from hardwood (SB) were selected. The results of aqueous adsorption showed the combination of biochar (WSP or SB) and BAp effectively removed Pb2+ from the aqueous solution containing 1000 ppm Pb2+. XRD, ATR-IR, and SEM/EDX results revealed the formation of hydroxypyromorphite on both biochars' surfaces. This study demonstrates that biochars could act as an efficient reaction platform for BAp and Pb2+ in aqueous solution due to their high surface area, porous structure, and high adsorption capacity. Therefore, it is mechanistically feasible to apply biochar to enhance BAp immobilization of Pb2+ in contaminated soil.}, journal={Chemosphere}, publisher={Elsevier BV}, author={Shen, Zhengtao and Tian, Da and Zhang, Xinyu and Tang, Lingyi and Su, Mu and Zhang, Li and Li, Zhen and Hu, Shuijin and Hou, Deyi}, year={2018}, month={Jan}, pages={260–266} }
 @article{ye_chen_hall_pan_yan_bai_guo_zhang_bai_hu_2018, title={Reconciling multiple impacts of nitrogen enrichment on soil carbon: plant, microbial and geochemical controls}, volume={21}, ISSN={["1461-0248"]}, DOI={10.1111/ele.13083}, abstractNote={Abstract}, number={8}, journal={ECOLOGY LETTERS}, author={Ye, Chenglong and Chen, Dima and Hall, Steven J. and Pan, Shang and Yan, Xuebin and Bai, Tongshuo and Guo, Hui and Zhang, Yi and Bai, Yongfei and Hu, Shuijin}, year={2018}, month={Aug}, pages={1162–1173} }
 @article{tian_wang_su_zheng_wu_wang_li_hu_2018, title={Remediation of lead-contaminated water by geological fluorapatite and fungus Penicillium oxalicum}, volume={25}, ISSN={0944-1344 1614-7499}, url={http://dx.doi.org/10.1007/S11356-018-2243-4}, DOI={10.1007/S11356-018-2243-4}, abstractNote={Phosphate-solubilizing fungi (PSF) can secrete large amounts of organic acids. In this study, the application of the fungus Penicillium oxalicum and geological fluorapatite (FAp) to lead immobilization was investigated. The formation and morphology of the lead-related minerals were analyzed by ATR-IR, XRD, Raman, and SEM. The quantity of organic acids secreted by P. oxalicum reached the maximum on the fourth day, which elevated soluble P concentrations from 0.4 to 108 mg/L in water. The secreted oxalic acid dominates the acidity in solution. P. oxalicum can survive in the solution with Pb concentration of ~ 1700 mg/L. In addition, it was shown that ~ 98% lead cations were removed while the fungus was cultured with Pb (~ 1700 mg/L) and FAp. The mechanism is that the released P from FAp (enhanced by organic acids) can react with Pb 2+  to form the stable pyromorphite mineral [Pb 5 (PO 4 ) 3 F]. The precipitation of lead oxalate also contributes to Pb immobilization. However, lead oxalate is more soluble due to its relatively high solubility. P. oxalicum has a higher rate of organic acid secretion compared with other typical PSF, e.g., Aspergillus niger. This study sheds light on bright future of applying P. oxalicum in Pb remediation.}, number={21}, journal={Environmental Science and Pollution Research}, publisher={Springer Science and Business Media LLC}, author={Tian, Da and Wang, Wenchao and Su, Mu and Zheng, Junyi and Wu, Yuanyi and Wang, Shimei and Li, Zhen and Hu, Shuijin}, year={2018}, month={May}, pages={21118–21126} }
 @article{zhang_zhang_zou_han_yan_li_hu_2018, title={Semi-quantitative analysis of microbial production of oxalic acid by montmorillonite sorption and ATR-IR}, volume={162}, ISSN={["1872-9053"]}, DOI={10.1016/j.clay.2018.07.006}, abstractNote={Interactions between organic acids and clay minerals significantly influence elemental cycle on Earth. Oxalic acid has been recognized as one of the most important secretions of soil microorganisms, for both typical bacterium Enterobacter sp. and fungus Aspergillus niger. This study examined the ATR-IR spectra of solid and aqueous oxalic acid. Then, sorption of dissolved oxalic acid, microbial secretion, and simulative acid solution onto montmorillonite were also studied by ATR-IR. The sorption significantly elevated intensity of the characteristic peak of oxalate at 1318 cm−1. Then, the intensity ratio (R) of 1318/1635 cm−1 was proposed as an accurate indicator for semi-quantitatively analyzing oxalic acid concentration. R values of ~0.13 and ~0.20 (for non-microorganism system) represented the oxalic acid concentrations of 600–800 ppm and ~2000 ppm respectively. Additionally, only oxalic acid with >800 ppm concentration can be identified appropriately if mixed with montmorillonite for 6 or 12 h, whereas 24 h shaking can decrease the detection line to as low as 100 ppm. Finally, we proposed an equation of Rcorrection = C0 ∗ Rmicrobe oxalic (with a coefficient C0 of 3.171) to estimate oxalic acid secreted by microorganisms. The coefficient was necessary due to the interference from multiple organic acids in microbial secretion. This equation worked successfully for both Enterobacter sp. and Aspergillus niger. It therefore is a reliable method for semi-quantitatively estimating microbial production of oxalic acid via montmorillonite sorption and ATR-IR technique.}, journal={APPLIED CLAY SCIENCE}, author={Zhang, Xinyu and Zhang, Lin and Zou, Xiang and Han, Feiyu and Yan, Ziping and Li, Zhen and Hu, Shuijin}, year={2018}, month={Sep}, pages={518–523} }
 @article{tao_bai_xiao_wang_wang_duryee_wang_zhang_hu_2018, title={Vertical distribution of ammonia-oxidizing microorganisms across a soil profile of the Chinese Loess Plateau and their responses to nitrogen inputs}, volume={635}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2018.04.104}, abstractNote={Ammonia-oxidizing archaea (AOA) and bacteria (AOB) oxidize ammonia into nitrite, the first and rate-limiting step of microbial nitrification, and exert major controls over soil nitrogen transformations. The Loess Plateau in northwest China is characterized with deep soils that are often exposed to the surface and reactive nitrogen (N) inputs due to erosion and human removal of the surface soil. However, few have examined the distribution of AOA and AOB along the profile of Loess Plateau soils and their responses to N inputs. We examined the abundance and diversity of AOA and AOB along the soil profile (0–100 cm) and their responses to two levels of N inputs (low at 10, and high at 100 μg N g−1 soil) in a 55-d incubation experiment. While AOB were most numerous in the surface soil (0–20 cm), AOA were most abundant in the subsoils (20–40 and 40–60 cm), suggesting a niche differentiation between AOA and AOB along the soil profile. High N input increased AOB nearly ten-fold in the upper two layers of soils (0–20 and 20–40 cm) and sixteen to twenty-five fold in the deeper soil layers (40–60, 60–80 and 80–100 cm). However, it only increased AOA by 7% (40–60 cm) to 48% (20–40 cm). In addition, potential nitrification rate and N2O emissions correlated only with AOB. Finally, high N input significantly increased AOB diversity and led to nitrite accumulation in deep soil layers (60–80 and 80–100 cm). Together, our results showed that high N input can significantly alter the diversity and function of ammonia-oxidizing microbes in the deep soil of Loess Plateau, suggesting the need to examine the generality of the observed changes and their potential environmental impacts.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Tao, Jinjin and Bai, Tongshuo and Xiao, Rui and Wang, Peng and Wang, Fuwei and Duryee, Alexander M. and Wang, Yi and Zhang, Yi and Hu, Shuijin}, year={2018}, month={Sep}, pages={240–248} }
 @article{wang_li_xing_ma_hu_tu_2017, title={Bio-organic Fertilizer Promotes Plant Growth and Yield and Improves Soil Microbial Community in Continuous Monoculture System of Chrysanthemum morifolium cv. Chuju}, volume={19}, ISSN={["1814-9596"]}, DOI={10.17957/ijab/15.0339}, abstractNote={Chuju, a cultivar of Chrysanthemum morifolium, has been growing for both drink and medicinal uses for hundreds of years in China. In recent years, however, continuous monoculture of Chuju has caused declines in growth and yields. In this study, we investigated the plant growth and yields, soil microbial community composition dynamics, and the improvements of bio-organic fertilizer on plant growth and yield in Chuju continuous cropping systems. Results showed that the yield of Chuju flowers was decreased by 11-37%, but Fusarium oxysporum and total fungus populations were respectively increased by 34-79% and 53-107% in soils continuously monocultured with Chuju for two to four years, as compared to those for one year. Bio-organic fertilizer significantly reduced F. oxysporum population and the ratio of F. oxysporum to total fungus population, but enhanced shoot biomass, flower diameter, and flower yields, in comparison with synthetic fertilizer. These results indicate that bio-organic fertilizer could be used to alleviate soil problems and to sustain crop production in continuous cropping systems of Chuju. © 2017 Friends Science Publishers}, number={3}, journal={INTERNATIONAL JOURNAL OF AGRICULTURE AND BIOLOGY}, author={Wang, Jianfei and Li, Xiaoliang and Xing, Suzhi and Ma, Zhongyou and Hu, Shuijin and Tu, Cong}, year={2017}, pages={563–568} }
 @article{liu_wang_yan_li_jiao_hu_2017, title={Biochar amendments increase the yield advantage of legume-based intercropping systems over monoculture}, volume={237}, ISSN={["1873-2305"]}, DOI={10.1016/j.agee.2016.12.026}, abstractNote={Biochar soil amendments are receiving increased attention as one strategy to improve soil quality and crop productivity. However, studies about how biochar affects crop productivity so far have mainly focused on single cropping systems. Few have examined the effects of biochar additions on intercrops. We conducted a field experiment that investigated the effects of biochar amendments on yield and nutrient uptake in an intercropping system where maize (Zea mays L.) was intercropped with either soybean (Glycine max L.) or peanut (Arachis hypogaea L.). The relative advantages of both yield and total nutrient content were calculated as land equivalent ratios (LER). Biochar amendments significantly increased the yield advantage in both maize/soybean and maize/peanut systems over the single crops. Similarly, they significantly enhanced the relative N and P uptake advantage. Using the 15N isotope dilution method, we examined the effect of biochar amendments on peanut N2-fixation and subsequent N transfer from peanut to maize in a root-box experiment. Biochar amendments of 10 and 20 g kg−1 soil increased peanut N fixation by 15.52% and 14.11%, and increased N transfer from peanut to maize by 32.66% and 36.07%, respectively. These results indicate that amending soil with biochar can amplify the benefits of legume-based intercropping by enhancing legume N fixation and facilitating N transfer from legume plants to co-existing cereal crops.}, journal={AGRICULTURE ECOSYSTEMS & ENVIRONMENT}, author={Liu, Ling and Wang, Yanfang and Yan, Xinwei and Li, Jiwei and Jiao, Nianyuan and Hu, Shuijin}, year={2017}, month={Jan}, pages={16–23} }
 @article{wu_chen_tu_qiu_burkey_reberg-horton_peng_hu_2017, title={CO2-induced alterations in plant nitrate utilization and root exudation stimulate N2O emissions}, volume={106}, ISSN={["0038-0717"]}, DOI={10.1016/j.soilbio.2016.11.018}, abstractNote={Atmospheric carbon dioxide enrichment (eCO2) often increases soil nitrous oxide (N2O) emissions, which has been largely attributed to increased denitrification induced by CO2-enhancement of soil labile C and moisture. However, the origin of the N remains unexplained. Emerging evidence suggests that eCO2 alters plant N preference in favor of ammonium (NH4+-N) over nitrate (NO3−-N). Yet, whether and how this attributes to the enhancement of N2O emissions has not been investigated. We conducted a microcosm experiment with wheat (Triticum aestivum L.) and tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) to examine the effects of eCO2 on soil N2O emissions in the presence of two N forms (NH4+-N or NO3−-N). Results obtained showed that N forms dominated eCO2 effects on plant and microbial N utilization, and thus soil N2O emissions. Elevated CO2 significantly increased the rate and the sum of N2O emissions by three to four folds when NO3−-N, but not NH4+-N, was supplied under both wheat and tall fescue. While enhanced N2O emission was more related to the reduced plant NO3−-N uptake under wheat, it concurred with increased labile C under tall fescue. In the presence of NO3−-N, significantly lower shoot biomass N and 15N, but higher plant biomass C:N ratio, microbial biomass C and N, and/or soil extractable C indicated that eCO2 constrained plant NO3−-N utilization and likely stimulated root exudation. We propose a new conceptual model in which eCO2-inhibition of plant NO3−-N uptake and/or CO2-enhancement of soil labile C enhances the N and/or C availability for denitrifiers and increases the intensity and/or the duration of N2O emissions. Together, these findings indicate that CO2-enhancement of soil N and labile C favors denitrification, suggesting that management of N fertilizers in intensive systems will likely become more challenging under future CO2 scenarios.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Wu, Keke and Chen, Dima and Tu, Cong and Qiu, Yunpeng and Burkey, Kent O. and Reberg-Horton, S. Chris and Peng, Shaolin and Hu, Shuijin}, year={2017}, month={Mar}, pages={9–17} }
 @article{xie_zhou_li_hu_zhang_zhang_wang_kong_2017, title={Characterization of ferulic acid removal from aqueous solution by H2O2-modified hydrothermal biochar produced from Chrysanthemum morifolium Ramat. cv. Chuju}, volume={26}, number={12}, journal={Fresenius Environmental Bulletin}, author={Xie, Y. and Zhou, C. and Li, F. Y. and Hu, S. J. and Zhang, Z. L. and Zhang, Z. and Wang, J. F. and Kong, W. F.}, year={2017}, pages={7478–7491} }
 @article{li_tang_zheng_tian_su_zhang_ma_hu_2017, title={Characterizing the Mechanisms of Lead Immobilization via Bioapatite and Various Clay Minerals}, volume={1}, ISSN={["2472-3452"]}, DOI={10.1021/acsearthspacechem.7b00016}, abstractNote={Immobilizing lead (Pb) in contaminated water and soils via mineralization is an emerging field of interest in environmental remediation. This study investigated the feasibility of applying bioapatite and typical clay minerals (kaolinite, palygorskite, and montmorillonite) to immobilize Pb2+ cations in water. The mechanisms of lead immobilization were studied by inductively coupled plasma optical emission spectrometry (ICP–OES), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). Montmorillonite shows the highest efficiency in Pb remediation (reduced from ∼2000 to 30 ppm) with the addition of bioapatite. The XRD and HRTEM results demonstrated that aqueous Pb removal efficiency is facilitated by bioapatite via reacting with Pb to form pyromorphite mineral [Pb5(PO4)3(F,Cl,OH)]. The high surface area and cation-exchange capability of montmorillonite allow its abundant absorption of Pb2+ and, hence, cause the enriched formation of pyromorphite on its surface. In contrast, the...}, number={3}, journal={ACS EARTH AND SPACE CHEMISTRY}, author={Li, Zhen and Tang, Lingyi and Zheng, Yangfan and Tian, Da and Su, Mu and Zhang, Fan and Ma, Shuojia and Hu, Shuijin}, year={2017}, month={May}, pages={152–157} }
 @article{ling_chen_guo_wei_bai_shen_hu_2017, title={Differential responses of soil bacterial communities to long-term N and P inputs in a semi-arid steppe}, volume={292}, ISSN={["1872-6259"]}, DOI={10.1016/j.geoderma.2017.01.013}, abstractNote={Both nitrogen (N) and phosphorus (P) may limit plant production in steppes and affect plant community structure. However, few studies have explored in detail the differences and similarities in the responses of belowground microbial communities to long-term N and P inputs. Using a high-throughput Illumina Miseq sequencing platform, we characterized the bacterial communities in a semi-arid steppe subjected to long-term N or P additions. Our results showed that both the Chao richness and Shannon's diversity were negatively correlated to N input rate, while only Chao richness was significantly and negatively correlated to P input rate. Also, both N and P additions altered the bacterial community structure. The bacterial community between plots of the same N or P input rate was much more dissimilar with the higher input level, indicating more severe niche differentiation in pots with higher N or P input. N Inputs significantly increased the relative abundance of the predicted copiotrophic groups (Proteobacteria and Firmicutes) but reduced the predicted oligotrophic groups (Acidobacteria, Nitrospirae, Chloroflexi), with the order Rhizobiales being most affected. P additions significantly affected only two phyla (Armatimonadetes and Chlorobi), which were positively correlated with P source. Results from the structural equation modelling (SEM) showed that N additions affected the bacterial community primarily by changing the pH, while P additions did so mainly by improving P availability. Our results suggest that the below-ground bacterial communities are more sensitive to N inputs, but P inputs can also play an important role in bacterial niche differentiation. These findings improve our understanding of bacterial responses to N and P inputs, and their impacts on bacterial-mediated processes, especially in the context of increasing anthropogenic nutrient inputs.}, journal={GEODERMA}, author={Ling, Ning and Chen, Dima and Guo, Hui and Wei, Jiaxin and Bai, Yongfei and Shen, Qirong and Hu, Shuijin}, year={2017}, month={Apr}, pages={25–33} }
 @article{li_su_tian_tang_zhang_zheng_hu_2017, title={Effects of elevated atmospheric CO2 on dissolution of geological fluorapatite in water and soil}, volume={599}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2017.05.100}, abstractNote={Most of phosphorus (P) is present as insoluble phosphorus-bearing minerals or organic forms in soil. Geological fluorapatite (FAp) is the dominant mineral-weathering source of P. In this study, FAp was added into water and soil under elevated CO2 to investigate the pathway of P release. Two types of soils (an acidic soil from subtropical China and a saline-alkali soil from Tibet Plateau, China) with similar total P content were studied. In the solution, increased CO2 in air enhanced the dissolution of FAp, i.e., from 0.04 to 1.18 ppm for P and from 2.48 to 13.61 ppm for Ca. In addition, release of Ca and P from FAp reached the maximum (2.14 ppm for P and 13.84 ppm for Ca) under the combination of elevated CO2 and NaCl due to the increasing ion exchange. Consistent with the results from the solution, CO2 elevation promoted P release more significantly (triple) in the saline-alkali soil than in the acidic soil. Therefore, saline-alkali soils in Tibet Plateau would be an important reservoir of available P under the global CO2 rise. This study sheds the light on understanding the geological cycle of phosphorus.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Li, Zhen and Su, Mu and Tian, Da and Tang, Lingyi and Zhang, Lin and Zheng, Yangfan and Hu, Shuijin}, year={2017}, month={Dec}, pages={1382–1387} }
 @article{zheng_mamuti_liu_shu_hu_wang_li_lin_li_2017, title={Effects of nutrient additions on litter decomposition regulated by phosphorus-induced changes in litter chemistry in a subtropical forest, China}, volume={400}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2017.06.002}, abstractNote={Nutrient additions directly alter exogenous nutrient availability in soil, and then affect endogenous nutrient concentration in litter (i.e., litter chemistry), modifying litter decomposition. However, how nutrient-induced changes in litter chemistry interacting with altered soil nutrients affect litter decomposition remain unclear. In this study, three field experiments with reciprocal transplants using litter bags were conducted in a phosphorous (P) limiting subtropical forest with control, nitrogen addition (+N), P addition (+P), and +NP treatments to examine effects of exogenous and endogenous nutrient availability on litter decomposition. Our results showed that, in Experiment I, decomposition of litter collected from the control plots was significantly inhibited by 16% under both +P and +NP treatments and reversed to become net P accumulation from P release compared to that in the control. In Experiment II, since litter collected from +P and +NP plots had higher litter P, lower C/P and N/P, its decomposition was significantly faster in the control plots by 9% and 26%, respectively, with the faster release of N and P in the litter. The in situ Experiment III found that +P and +NP treatments reduced litter decomposition by 6% and 14%, respectively, but +N did not affect it compared to the control. Our results indicate that effects of P addition on litter decomposition were mediated by P-induced changes in litter chemistry, which need to be incorporated into land surface models for predicting effects of nutrient deposition on ecosystem C cycling and assessing the climate-biosphere feedbacks. Effects of nutrient additions on litter decomposition were regulated by P-induced changes in litter chemistry.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Zheng, Zemei and Mamuti, Meiliban and Liu, Heming and Shu, Yuqin and Hu, Shuijin and Wang, Xihua and Li, Binbin and Lin, Li and Li, Xu}, year={2017}, month={Sep}, pages={123–128} }
 @article{pan_liu_mo_patterson_duan_tian_hu_tang_2017, title={Erratum: Corrigendum: Effects of Nitrogen and Shading on Root Morphologies, Nutrient Accumulation, and Photosynthetic Parameters in Different Rice Genotypes}, volume={7}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/SREP45611}, DOI={10.1038/SREP45611}, abstractNote={Scientific Reports 6: Article number: 32148; published online: 25 August 2016; updated: 30 March 2017 The original version of this Article contained a typographical error in the spelling of the author Shuijin Hu, which was incorrectly given as Shuijing Hu. This has now been corrected in the PDF and HTML versions of the Article.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Pan, Shenggang and Liu, Haidong and Mo, Zhaowen and Patterson, Bob and Duan, Meiyang and Tian, Hua and Hu, Shuijin and Tang, Xiangru}, year={2017}, month={Mar} }
 @article{jiang_groenigen_huang_hungate_kessel_hu_zhang_wu_yan_wang_et al._2017, title={Higher yields and lower methane emissions with new rice cultivars}, volume={23}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.13737}, abstractNote={Abstract}, number={11}, journal={GLOBAL CHANGE BIOLOGY}, author={Jiang, Yu and Groenigen, Kees Jan and Huang, Shan and Hungate, Bruce A. and Kessel, Chris and Hu, Shuijin and Zhang, Jun and Wu, Lianhai and Yan, Xiaojun and Wang, Lili and et al.}, year={2017}, month={Nov}, pages={4728–4738} }
 @article{wells_reberg-horton_mirsky_maul_hu_2017, title={In situ validation of fungal N translocation to cereal rye mulches under no-till soybean production}, volume={410}, ISSN={0032-079X 1573-5036}, url={http://dx.doi.org/10.1007/S11104-016-2989-8}, DOI={10.1007/S11104-016-2989-8}, abstractNote={The ability of grass mulches to inhibit weed performance has been linked to their limitations on nitrogen availability to the weeds. Fungal translocation of N from the soil to the surface mulch has been confirmed in laboratories, but this mechanism has not been documented under field conditions. Experiments used 15N (NH4)2SO4 , 99.7 at.%, which was uniformly injected below the soil surface at a rate of 1 mg 15 N kg−1 soil. Some plots were treated with a fungicide (Captan) every 2 weeks after injection, while others were not treated. Nitrogen transfer was monitored by measuring levels in surface residue, soybean tissue, and extractable soil inorganic N pools. Despite the N release from the cereal rye (Secale cereale L.) tissues ranging from 15 to 50 kg N ha−1, there was a detectable increase in 15N enrichment of 10–15 % in the cereal rye tissue. Six weeks after injection, tissue from the plots not treated with fungicide contained 36 % more 15 N. The increased 15N enrichment in the cereal rye mulch supports laboratory observations that soil inorganic N is translocated into surface mulch via fungal mechanisms. These findings illustrate microbial-mediated sinks for nitrogen in cereal rye mulches in no-till soybean production systems.}, number={1-2}, journal={Plant and Soil}, publisher={Springer Nature}, author={Wells, M. Scott and Reberg-Horton, S. Chris and Mirsky, Steven B. and Maul, Jude E. and Hu, Shuijin}, year={2017}, pages={153–165} }
 @article{guo_ye_zhang_pan_ji_li_liu_zhou_du_hu_et al._2017, title={Long-term nitrogen & phosphorus additions reduce soil microbial respiration but increase its temperature sensitivity in a Tibetan alpine meadow}, volume={113}, ISSN={["0038-0717"]}, DOI={10.1016/j.soilbio.2017.05.024}, abstractNote={Nutrient availability may exert major controls over soil microbial respiration, especially in carbon (C)-rich, nitrogen (N)-limited ecosystems in high elevation regions, but how soil organic matter (SOM) decomposition and its temperature sensitivity respond to long-term N & P additions in alpine ecosystems remains unclear. We examined the impact of long-term (15 yr) N & P additions on soil microbial respiration and its temperature sensitivity (Q10), and assessed the relative importance of nutrient-induced alterations in substrate quality and the microbial community composition in explaining the variation in soil respiration and temperature sensitivity. We found that N & P additions significantly reduced microbial respiration rates and cumulative C efflux, but increased the Q10 (15/5 °C). Also, N & P additions reduced the biomass of the whole microbial community, gram negative bacteria and fungi, but increased the aromaticity and aliphaticity of soil organic C substrate. Across the treatments, averaged Q10 was positively correlated with the complexity of SOM as characterized by 13C-NMR, supporting the prediction based on kinetic theory that SOM with recalcitrant molecular structure is with high temperature sensitivity. Together, our results showed that changes in both substrate quality and soil microbial community induced by long-term nutrient inputs may alter the response of soil microbial respiration to elevated temperature. Because the positive effects of increasing temperature sensitivity for use of lower quality substrates on C emission may be offset by lower absolute rates at any one temperature, long-term N & P additions increase the uncertainty in predicting the net soil C losses in the scenario of warming on Tibetan Plateau.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Guo, Hui and Ye, Chenglong and Zhang, Hao and Pan, Shang and Ji, Yangguang and Li, Zhen and Liu, Manqiang and Zhou, Xianhui and Du, Guozhen and Hu, Feng and et al.}, year={2017}, month={Oct}, pages={26–34} }
 @article{wang_li_tu_hoyt_deforest_hu_2017, title={Long-term no-tillage and organic input management enhanced the diversity and stability of soil microbial community}, volume={609}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2017.07.053}, abstractNote={Intensive tillage and high inputs of chemicals are frequently used in conventional agriculture management, which critically depresses soil properties and causes soil erosion and nonpoint source pollution. Conservation practices, such as no-tillage and organic farming, have potential to enhance soil health. However, the long-term impact of no-tillage and organic practices on soil microbial diversity and community structure has not been fully understood, particularly in humid, warm climate regions such as the southeast USA. We hypothesized that organic inputs will lead to greater microbial diversity and a more stable microbial community, and that the combination of no-tillage and organic inputs will maximize soil microbial diversity. We conducted a long-term experiment in the southern Appalachian mountains of North Carolina, USA to test these hypotheses. The results showed that soil microbial diversity and community structure diverged under different management regimes after long term continuous treatments. Organic input dominated the effect of management practices on soil microbial properties, although no-tillage practice also exerted significant impacts. Both no-tillage and organic inputs significantly promoted soil microbial diversity and community stability. The combination of no-tillage and organic management increased soil microbial diversity over the conventional tillage and led to a microbial community structure more similar to the one in an adjacent grassland. These results indicate that effective management through reducing tillage and increasing organic C inputs can enhance soil microbial diversity and community stability.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Wang, Yi and Li, Chunyue and Tu, Cong and Hoyt, Greg D. and DeForest, Jared L. and Hu, Shuijin}, year={2017}, month={Dec}, pages={341–347} }
 @article{zeng_yang_xuan_dai_hu_hu_zhong_li_gao_wang_et al._2017, title={Longitudinal Study of the Effects of Environmental pH on the Mechanical Properties of Aspergillus niger}, volume={3}, ISSN={["2373-9878"]}, DOI={10.1021/acsbiomaterials.6b00294}, abstractNote={The regulation of environmental pH is key to the health of an ecosystem, influencing the metabolic activity, growth, and development of organisms within it. Although pH values can be measured by a wide range of readily available technologies ranging from fluorescent dyes and nanosensors, these cannot reveal the history of environmental pH from before monitoring begins. This information is sometimes crucial for piecing together what has happened to an ecosystem, and our long-term goal is therefore to develop technologies capable of obtaining it. Here, we propose monitoring environmental pH over time by tracking mechanical properties of a common fungus. As a first step toward obtaining a time history of pH, we evaluate the effect of pH upon the effective indentation modulus of spores and hyphae of Aspergillus niger. We report that the indentation modulus of this phosphorus-solubilizing fungus, obtained through atomic force microscopy and nanoindentation, correlated with environmental acidity. We observed a significant, monotonic increase in moduli over the course of incubation in an acidic environment, but no change in moduli over time for incubation in a neutral environment. Results show promise for using our scheme to detect and track environmental pH over time, and more broadly for using a microorganism's mechanical properties as a biomarker for environmental detection.}, number={11}, journal={ACS BIOMATERIALS SCIENCE & ENGINEERING}, author={Zeng, Wenjun and Yang, Hua and Xuan, Guanghui and Dai, Letian and Hu, Yunxiao and Hu, Shuijin and Zhong, Shengkui and Li, Zhen and Gao, Mingyuan and Wang, Shimei and et al.}, year={2017}, month={Nov}, pages={2974–2979} }
 @article{yu_xiao_hu_polizzotto_zhao_mcgrath_li_ran_shen_2017, title={Mineral Availability as a Key Regulator of Soil Carbon Storage}, volume={51}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.7b00305}, abstractNote={Mineral binding is a major mechanism for soil carbon (C) stabilization, and mineral availability for C binding critically affects C storage. Yet, the mechanisms regulating mineral availability are poorly understood. Here, we showed that organic amendments in three long-term (23, 154, and 170 yrs, respectively) field experiments significantly increased mineral availability, particularly of short-range-ordered (SRO) phases. Two microcosm studies demonstrated that the presence of roots significantly increased mineral availability and promoted the formation of SRO phases. Mineral transformation experiments and isotopic labeling experiments provided direct evidence that citric acid, a major component of root exudates, promoted the formation of SRO minerals, and that SRO minerals acted as "nuclei" for C retention. Together, these findings indicate that soil organic amendments initialize a positive feedback loop by increasing mineral availability and promoting the formation of SRO minerals for further C binding, thereby possibly serving as a management tool for enhancing carbon storage in soils.}, number={9}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Yu, Guanghui and Xiao, Jian and Hu, Shuijin and Polizzotto, Matthew L. and Zhao, Fangjie and McGrath, Steve P. and Li, Huan and Ran, Wei and Shen, Qirong}, year={2017}, month={May}, pages={4960–4969} }
 @article{ye_bai_yang_zhang_guo_li_li_hu_2017, title={Physical access for residue-mineral interactions controls organic carbon retention in an Oxisol soil}, volume={7}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-017-06654-6}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Ye, Chenglong and Bai, Tongshuo and Yang, Yi and Zhang, Hao and Guo, Hui and Li, Zhen and Li, Huixin and Hu, Shuijin}, year={2017}, month={Jul} }
 @article{hu_zhu_chen_bonkowski_griffiths_chen_zhu_hu_hu_liu_2017, title={Responses of rice paddy micro-food webs to elevated CO2 are modulated by nitrogen fertilization and crop cultivars}, volume={114}, ISSN={0038-0717}, url={http://dx.doi.org/10.1016/J.SOILBIO.2017.07.008}, DOI={10.1016/J.SOILBIO.2017.07.008}, abstractNote={Elevated atmospheric CO2 concentrations (eCO2) often increase plant growth but simultaneously lead to the nitrogen (N) limitation in soil. The corresponding mitigation strategy such as supplementing N fertilizer and growing high-yielding cultivars at eCO2 would further modify soil ecosystem structure and function. Little attention has, however, been directed toward assessing the responses of soil food web. We report results from a long-term free air CO2 enrichment (FACE) experiment in a rice paddy agroecosystem that examined the responses of soil micro-food webs to eCO2 and exogenous nitrogen fertilization (eN) in the rhizosphere of two rice cultivars with distinctly weak and strong responses to eCO2. Soil micro-food web parameters, including microfauna (protists and nematodes) and soil microbes (bacteria and fungi from phospholipid fatty acid (PLFA) analysis), as well as soil C and N variables, were determined at the heading and ripening stages of rice. Results showed that eCO2 effects on soil micro-food webs depended strongly on N fertilization, rice cultivar and growth stage. eCO2 stimulated the fungal energy channel at the ripening stage, as evidenced by increases in fungal biomass (32%), fungi:bacteria ratio (18%) and the abundance of fungivorous nematodes (64%), mainly due to an enhanced carbon input. The eN fueled the bacterial energy channel by increasing the abundance of flagellates and bacterivorous nematodes, likely through alleviating the N-limitation of plants and rhizosphere under eCO2. While eCO2 decreased the abundance of herbivorous nematodes under the weak-responsive cultivar by 59% and 47% with eN at the heading and ripening stage, respectively, the numbers of herbivorous nematodes almost tripled (×2.9; heading) and doubled (×1.6; ripening) under the strong-responsive cultivar with eCO2 at eN due to higher root quantity and quality. Structural equation model (SEM) showed that lower trophic-level organisms were affected by bottom-up forces of altered soil resources induced by eCO2 and eN, and effects on higher trophic level organisms were driven by bottom-up cascades with 69% of the variation being explained. Taken together, strategies to adapt climate change by growing high-yielding crop cultivars under eCO2 may face a trade-off by negative soil feedbacks through the accumulation of root-feeding crop pest species.}, journal={Soil Biology and Biochemistry}, publisher={Elsevier BV}, author={Hu, Zhengkun and Zhu, Chunwu and Chen, Xiaoyun and Bonkowski, Michael and Griffiths, Bryan and Chen, Fajun and Zhu, Jianguo and Hu, Shuijin and Hu, Feng and Liu, Manqiang}, year={2017}, month={Nov}, pages={104–113} }
 @article{yang_zhang_koide_hoeksema_tang_bian_hu_chen_2017, title={Taxonomic resolution is a determinant of biodiversity effects in arbuscular mycorrhizal fungal communities}, volume={105}, ISSN={["1365-2745"]}, DOI={10.1111/1365-2745.12655}, abstractNote={Summary}, number={1}, journal={JOURNAL OF ECOLOGY}, author={Yang, Haishui and Zhang, Qian and Koide, Roger T. and Hoeksema, Jason D. and Tang, Jianjun and Bian, Xinmin and Hu, Shuijin and Chen, Xin}, year={2017}, month={Jan}, pages={219–228} }
 @misc{chen_wang_meng_yang_jiang_zou_li_hu_2017, title={Temperature-related changes of Ca and P release in synthesized hydroxylapatite, geological fluorapatite, and bone bioapatite}, volume={451}, ISSN={["1878-5999"]}, DOI={10.1016/j.chemgeo.2017.01.014}, abstractNote={Solubility of apatite is highly addressed in mineralogical and material studies. Heating is one of the major processes in apatite industry. In this study, synthesized hydroxylapatite (HAp), geological fluorapatite (FAp), and bone bioapatite (BAp) were heated at various temperatures (100–900 °C) for analyses. The mineralogy and solubility of the three apatites were analyzed by XRD, ATR–IR, and ICP. Release of Ca and P in water for BAp reaches the maximum when heated at 200 °C, i.e., 0.215 mmol/L for Ca and 0.106 mmol/L for P. The value is higher than the maximum values (heated at 900 °C) of the solubility for HAp and FAp. The heating temperature at 600 °C is a re-crystallization point for all the three types of apatites. Especially, the crystallinity of BAp is significantly elevated at > 600 °C. Phase of geological FAp is relatively stable during heating up to 900 °C. Phase of β-TCP is present when heating HAp at 800 to 900 °C. In addition, BAp is transformed to the resemblance of HAp. However, no β-TCP was detected for BAp during heating between 800 and 900 °C, which is probably due to its Ca-deficiency. This study elucidates the correlation of phase changes of BAp and its solubility during heating, which sheds the light on its application as materials and fertilizer.}, journal={CHEMICAL GEOLOGY}, author={Chen, Weikun and Wang, Quanzhi and Meng, Shiting and Yang, Ping and Jiang, Liu and Zou, Xiang and Li, Zhen and Hu, Shuijin}, year={2017}, month={Feb}, pages={183–188} }
 @article{guo_hu_gao_xie_ling_shen_hu_guo_2017, title={The rice production practices of high yield and high nitrogen use efficiency in Jiangsu, China}, volume={7}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-017-02338-3}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Guo, Jiuxin and Hu, Xiangyu and Gao, Limin and Xie, Kailiu and Ling, Ning and Shen, Qirong and Hu, Shuijin and Guo, Shiwei}, year={2017}, month={May} }
 @article{li_bai_dai_wang_tao_meng_hu_wang_hu_2016, title={A study of organic acid production in contrasts between two phosphate solubilizing fungi: Penicillium oxalicum and Aspergillus niger}, volume={6}, ISSN={["2045-2322"]}, DOI={10.1038/srep25313}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Li, Zhen and Bai, Tongshuo and Dai, Letian and Wang, Fuwei and Tao, Jinjin and Meng, Shiting and Hu, Yunxiao and Wang, Shimei and Hu, Shuijin}, year={2016}, month={Apr} }
 @article{chen_cheng_chu_mi_hu_xie_tuvshintogtokh_bai_2016, title={Effect of diversity on biomass across grasslands on the Mongolian Plateau: contrasting effects between plants and soil nematodes}, volume={43}, ISSN={["1365-2699"]}, DOI={10.1111/jbi.12683}, abstractNote={Abstract}, number={5}, journal={JOURNAL OF BIOGEOGRAPHY}, author={Chen, Dima and Cheng, Junhui and Chu, Pengfei and Mi, Jia and Hu, Shuijin and Xie, Yichun and Tuvshintogtokh, Indree and Bai, Yongfei}, year={2016}, month={May}, pages={955–966} }
 @article{pan_liu_mo_patterson_duan_tian_hu_tang_2016, title={Effects of Nitrogen and Shading on Root Morphologies, Nutrient Accumulation, and Photosynthetic Parameters in Different Rice Genotypes}, volume={6}, ISSN={["2045-2322"]}, DOI={10.1038/srep32148}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Pan, Shenggang and Liu, Haidong and Mo, Zhaowen and Patterson, Bob and Duan, Meiyang and Tian, Hua and Hu, Shuijing and Tang, Xiangru}, year={2016}, month={Aug} }
 @article{hu_wang_gu_tao_zhang_hu_zhu_meng_2016, title={Effects of different straw returning modes on greenhouse gas emissions and crop yields in a rice-wheat rotation system}, volume={223}, ISSN={["1873-2305"]}, DOI={10.1016/j.agee.2016.02.027}, abstractNote={Significant efforts have been made to assess the common straw returning modes on crop yields and greenhouse gas (GHG) emissions. However, the effects of a novel straw returning mode, namely ditch-buried straw returning on GHG emissions are still unknown. We conducted a 2-year field experiment, including four wheat straw returning modes (no straw returning (CK), wheat straw returning with rotary tillage (WR), wheat straw returning with plowing (WP), and ditch-buried wheat straw returning (WD)) to evaluate crop yields and GHG emissions under rice–wheat rotation system. Methane (CH4) and nitrous oxide (N2O) fluxes were measured using the static chamber method from the 2013 rice season to 2015 wheat season. The results indicated that wheat straw returning treatments before rice transplantation significantly increased seasonal CH4 emissions during both the rice seasons and wheat seasons, compared to CK. Annual CH4 emission was lower under WD than that under WR and WP. Straw returning significantly increased N2O emission during the first rice season and second wheat season, compared to CK. Annual N2O emission under WD was significantly lower than that under WP, but significantly higher than that under WR and CK. Straw returning increased both rice and wheat yields compared with CK, and WD had significantly higher annual grain yields of both rice and wheat, with an increase of 7.1%. Across the two rotation cycles, annual yield-scaled GWP of CH4 and N2O emissions under WD was 10.8% lower than that of WR. These results indicated that compared with straw returning via rotary tillage or plowing, ditch-buried wheat straw in rice seasons may reduce GHG emissions while sustaining or even increasing crop yields in the rice–wheat rotation system.}, journal={AGRICULTURE ECOSYSTEMS & ENVIRONMENT}, author={Hu, Naijuan and Wang, Baojun and Gu, Zehai and Tao, Baorui and Zhang, Zhengwen and Hu, Shuijin and Zhu, Liqun and Meng, Yali}, year={2016}, month={May}, pages={115–122} }
 @article{chen_pan_bai_hu_huang_wang_naeem_elser_wu_han_2016, title={Effects of plant functional group loss on soil biota and net ecosystem exchange: a plant removal experiment in the Mongolian grassland}, volume={104}, ISSN={["1365-2745"]}, DOI={10.1111/1365-2745.12541}, abstractNote={Summary}, number={3}, journal={JOURNAL OF ECOLOGY}, author={Chen, Dima and Pan, Qingmin and Bai, Yongfei and Hu, Shuijin and Huang, Jianhui and Wang, Qibing and Naeem, Shahid and Elser, James J. and Wu, Jianguo and Han, Xingguo}, year={2016}, month={May}, pages={734–743} }
 @article{li_hu_polizzotto_chang_shen_ran_yu_2016, title={Fungal biomineralization of montmorillonite and goethite to short-range-ordered minerals}, volume={191}, ISSN={["1872-9533"]}, DOI={10.1016/j.gca.2016.07.009}, abstractNote={Highly reactive nano-scale minerals, e.g., short-range-ordered minerals (SROs) and other nanoparticles, play an important role in soil carbon (C) retention. Yet, the mechanisms that govern biomineralization from bulk minerals to highly reactive nano-scale minerals remain largely unexplored, which critically hinders our efforts toward managing nano-scale minerals for soil C retention. Here we report the results from a study that explores structural changes during Aspergillus fumigatus Z5 transformation of montmorillonite and goethite to SROs. We examined the morphology and structure of nano-scale minerals, using high-resolution transmission electron microscopy, time-resolved solid-state 27Al and 29Si NMR, and Fe K-edge X-ray absorption fine structure spectroscopy combined with two dimensional correlation spectroscopy (2D COS) analysis. Our results showed that after a 48-h cultivation of montmorillonite and goethite with Z5, new biogenic intracellular and extracellular reactive nano-scale minerals with a size of 3–5 nm became abundant. Analysis of 2D COS further suggested that montmorillonite and goethite were the precursors of the dominant biogenic nano-scale minerals. Carbon 1s near edge X-ray absorption fine structure (NEXAFS) spectra and their deconvolution results demonstrated that during fungus Z5 growth, carboxylic C (288.4–289.1 eV) was the dominant organic group, accounting for approximately 34% and 59% in the medium and aggregates, respectively. This result suggested that high percentage of the production of organic acids during the growth of Z5 was the driving factor for structural changes during biomineralization. This is, to the best of our knowledge, the first report of the structural characterization of nano-scale minerals by 2D COS, highlighting its potential to elucidate biomineralization pathways and thus identify the precursors of nano-scale minerals.}, journal={GEOCHIMICA ET COSMOCHIMICA ACTA}, author={Li, Huan and Hu, Shuijin and Polizzotto, Matthew L. and Chang, Xiaoli and Shen, Qirong and Ran, Wei and Yu, Guanghui}, year={2016}, month={Oct}, pages={17–31} }
 @article{li_wang_bai_tao_guo_yang_wang_hu_2016, title={Lead immobilization by geological fluorapatite and fungus Aspergillus niger}, volume={320}, ISSN={["1873-3336"]}, DOI={10.1016/j.jhazmat.2016.08.051}, abstractNote={Phosphate solubilizing fungi have high ability to secrete organic acids. In this study, fungus Aspergillus niger and geological fluorapatite were applied in lead remediation in aqueous solution. Formation and morphology of the lead minerals, e.g., pyromorphite and lead oxalate, were investigated by SEM, XRD, and ATR-IR. The total quantity of organic acids reached the maximum at the sixth day, which improved the concentration of soluble P up to ∼370 mg/L from ∼0.4 mg/L. The organic acids, especially the oxalic acid, enhance the solubility of fluorapatite significantly. The stable fluoropyromorphite [Pb5(PO4)3F] is precipitated with the elevated solubility of fluorapatite in the acidic environment. Furthermore, A. niger grows normally with the presence of lead cations. It is shown that >99% lead cations can be removed from the solution. However, immobilization caused by the precipitation of lead oxalate cannot be ignored if the fungus A. niger was cultured in the Pb solution. This study elucidates the mechanisms of lead immobilization by FAp and A. niger, and sheds its perspective in lead remediation, especially for high Pb concentration solution.}, journal={JOURNAL OF HAZARDOUS MATERIALS}, author={Li, Zhen and Wang, Fuwei and Bai, Tongshuo and Tao, Jinjin and Guo, Jieyun and Yang, Mengying and Wang, Shimei and Hu, Shuijin}, year={2016}, month={Dec}, pages={386–392} }
 @inproceedings{crews_bravo_smith_2016, title={Model development for pzt bimorph actuation employed for micro-air vehicles}, booktitle={Proceedings of the asme conference on smart materials adaptive}, author={Crews, J. and Bravo, N. and Smith, R.}, year={2016} }
 @article{chandrasekaran_kim_krishnamoorthy_walitang_sundaram_joe_selvakumar_hu_oh_sa_2016, title={Mycorrhizal Symbiotic Efficiency on C-3 and C-4 Plants under Salinity Stress - A Meta-Analysis}, volume={7}, ISSN={["1664-302X"]}, DOI={10.3389/fmicb.2016.01246}, abstractNote={A wide range of C3 and C4 plant species could acclimatize and grow under the impact of salinity stress. Symbiotic relationship between plant roots and arbuscular mycorrhizal fungi (AMF) are widespread and are well known to ameliorate the influence of salinity stress on agro-ecosystem. In the present study, we sought to understand the phenomenon of variability on AMF symbiotic relationship on saline stress amelioration in C3 and C4 plants. Thus, the objective was to compare varied mycorrhizal symbiotic relationship between C3 and C4 plants in saline conditions. To accomplish the above mentioned objective, we conducted a random effects models meta-analysis across 60 published studies. An effect size was calculated as the difference in mycorrhizal responses between the AMF inoculated plants and its corresponding control under saline conditions. Responses were compared between (i) identity of AMF species and AMF inoculation, (ii) identity of host plants (C3 vs. C4) and plant functional groups, (iii) soil texture and level of salinity and (iv) experimental condition (greenhouse vs. field). Results indicate that both C3 and C4 plants under saline condition responded positively to AMF inoculation, thereby overcoming the predicted effects of symbiotic efficiency. Although C3 and C4 plants showed positive effects under low (EC < 4 ds/m) and high (>8 ds/m) saline conditions, C3 plants showed significant effects for mycorrhizal inoculation over C4 plants. Among the plant types, C4 annual and perennial plants, C4 herbs and C4 dicot had a significant effect over other counterparts. Between single and mixed AMF inoculants, single inoculants Rhizophagus irregularis had a positive effect on C3 plants whereas Funneliformis mosseae had a positive effect on C4 plants than other species. In all of the observed studies, mycorrhizal inoculation showed positive effects on shoot, root and total biomass, and in nitrogen, phosphorous and potassium (K) uptake. However, it showed negative effects in sodium (Na) uptake in both C3 and C4 plants. This influence, owing to mycorrhizal inoculation, was significantly higher in K uptake in C4 plants. For our analysis, we concluded that AMF-inoculated C4 plants showed more competitive K+ ions uptake than C3 plants. Therefore, maintenance of high cytosolic K+/Na+ ratio is a key feature of plant salt tolerance. Studies on the detailed mechanism for the selective transport of K in C3 and C4 mycorrhizal plants under salt stress is lacking, and this needs to be explored.}, journal={FRONTIERS IN MICROBIOLOGY}, author={Chandrasekaran, Murugesan and Kim, Kiyoon and Krishnamoorthy, Ramasamy and Walitang, Denver and Sundaram, Subbiah and Joe, Manoharan M. and Selvakumar, Gopal and Hu, Shuijin and Oh, Sang-Hyon and Sa, Tongmin}, year={2016}, month={Aug} }
 @article{luo_mazer_guo_zhang_weiner_hu_2016, title={Nitrogen:phosphorous supply ratio and allometry in five alpine plant species}, volume={6}, ISSN={2045-7758}, url={http://dx.doi.org/10.1002/ECE3.2587}, DOI={10.1002/ECE3.2587}, abstractNote={Abstract}, number={24}, journal={Ecology and Evolution}, publisher={Wiley}, author={Luo, Xi and Mazer, Susan J. and Guo, Hui and Zhang, Nan and Weiner, Jacob and Hu, Shuijin}, year={2016}, month={Nov}, pages={8881–8892} }
 @article{jiang_huang_zhang_zhang_zhang_zheng_deng_zhang_wu_hu_et al._2016, title={Optimizing rice plant photosynthate allocation reduces N2O emissions from paddy fields}, volume={6}, ISSN={["2045-2322"]}, DOI={10.1038/srep29333}, abstractNote={Abstract}, journal={SCIENTIFIC REPORTS}, author={Jiang, Yu and Huang, Xiaomin and Zhang, Xin and Zhang, Xingyue and Zhang, Yi and Zheng, Chengyan and Deng, Aixing and Zhang, Jun and Wu, Lianhai and Hu, Shuijin and et al.}, year={2016}, month={Jul} }
 @article{chen_li_lan_hu_bai_2016, title={Soil acidification exerts a greater control on soil respiration than soil nitrogen availability in grasslands subjected to long-term nitrogen enrichment}, volume={30}, ISSN={["1365-2435"]}, DOI={10.1111/1365-2435.12525}, abstractNote={Summary}, number={4}, journal={FUNCTIONAL ECOLOGY}, author={Chen, Dima and Li, Jianjun and Lan, Zhichun and Hu, Shuijin and Bai, Yongfei}, year={2016}, month={Apr}, pages={658–669} }
 @article{jani_grossman_smyth_hu_2016, title={Winter legume cover-crop root decomposition and N release dynamics under disking and roller-crimping termination approaches}, volume={31}, ISSN={1742-1705 1742-1713}, url={http://dx.doi.org/10.1017/S1742170515000113}, DOI={10.1017/S1742170515000113}, abstractNote={Abstract}, number={3}, journal={Renewable Agriculture and Food Systems}, publisher={Cambridge University Press (CUP)}, author={Jani, Arun D. and Grossman, Julie and Smyth, Thomas J. and Hu, Shuijin}, year={2016}, pages={214–229} }
 @article{chen_wang_lan_li_xing_hu_bai_2015, title={Biotic community shifts explain the contrasting responses of microbial and root respiration to experimental soil acidification}, volume={90}, ISSN={["0038-0717"]}, DOI={10.1016/j.soilbio.2015.08.009}, abstractNote={Soil respiration is comprised primarily of root and microbial respiration, and accounts for nearly half of the total CO2 efflux from terrestrial ecosystems. Soil acidification resulting from acid deposition significantly affects soil respiration. Yet, the mechanisms that underlie the effects of acidification on soil respiration and its two components remain unclear. We collected data on sources of soil CO2 efflux (microbial and root respiration), above- and belowground biotic communities, and soil properties in a 4-year field experiment with seven levels of acid in a semi-arid Inner Mongolian grassland. Here, we show that soil acidification has contrasting effects on root and microbial respiration in a typical steppe grassland. Soil acidification increases root respiration mainly by an increase in root biomass and a shift to plant species with greater specific root respiration rates. The shift of plant community from perennial bunchgrasses to perennial rhizome grasses was in turn regulated by the decreases in soil base cations and N status. In contrast, soil acidification suppresses microbial respiration by reducing total microbial biomass and enzymatic activities, which appear to result from increases in soil H+ ions and decreases in soil base cations. Our results suggest that shifts in both plant and microbial communities dominate the responses of soil respiration and its components to soil acidification. These results also indicate that carbon cycling models concerned with future climate change should consider soil acidification as well as shifts in biotic communities.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Chen, Dima and Wang, Yang and Lan, Zhichun and Li, Jianjun and Xing, Wen and Hu, Shuijin and Bai, Yongfei}, year={2015}, month={Nov}, pages={139–147} }
 @article{xing_wang_zhou_bloszies_tu_hu_2015, title={EFFECTS OF NH4+- N/NO3--N RATIOS ON PHOTOSYNTHETIC CHARACTERISTICS, DRY MATTER YIELD AND NITRATE CONCENTRATION OF SPINACH}, volume={51}, ISSN={["1469-4441"]}, DOI={10.1017/s0014479714000192}, abstractNote={SUMMARY}, number={1}, journal={EXPERIMENTAL AGRICULTURE}, author={Xing, Suzhi and Wang, Jianfei and Zhou, Yi and Bloszies, Sean A. and Tu, Cong and Hu, Shuijin}, year={2015}, month={Jan}, pages={151–160} }
 @article{chen_lan_hu_bai_2015, title={Effects of nitrogen enrichment on belowground communities in grassland: Relative role of soil nitrogen availability vs. soil acidification}, volume={89}, ISSN={["0038-0717"]}, DOI={10.1016/j.soilbio.2015.06.028}, abstractNote={Terrestrial ecosystems worldwide are receiving increasing amounts of biologically reactive nitrogen (N) as a consequence of anthropogenic activities. This intended or unintended fertilization can have a wide range of impacts on the above- and belowground communities. An increase in high N availability has been assumed to be a major mechanism enhancing the abundance of above- and belowground communities. In addition to increasing available N, however, N enrichment causes soil acidification, which may negatively affect above- and belowground communities. The relative importance of increased N availability vs. increased soil acidity for above- and belowground communities in natural ecosystems experiencing N enrichment is unclear. In a 12-year N enrichment experiment in a semi-arid grassland, N enrichment substantially increased both above- and belowground plant biomass mainly via the N availability-induced increase in biomass of perennial rhizome grasses. N enrichment also dramatically suppressed bacterial, fungal, and actinobacteria biomass mainly via the soil acidification pathway (acidification increased concentrations of H+ ions and Al3+ and decreased concentrations of mineral cations). In addition, N enrichment also suppressed bacterial-, fungal-feeding, and omnivorous + carnivorous nematodes mainly via the soil acidification pathway (acidification reduced nematode food resources and reduced concentrations of mineral cations). The positive effects resulting from the increase in belowground carbon allocation (via increase in quantity and quality of plant production) on belowground communities were outweighed by the negative effects resulting from soil acidification, indicating that N enrichment weakens the linkages between aboveground and belowground components of grassland ecosystems. Our results suggest that N enrichment-induced soil acidification should be included in models that predict biota communities and linkages to carbon and nitrogen cycling in terrestrial ecosystems under future scenarios of N deposition.}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Chen, Dima and Lan, Zhichun and Hu, Shuijin and Bai, Yongfei}, year={2015}, month={Oct}, pages={99–108} }
 @article{qiao_liu_hu_compton_greaver_li_2015, title={How inhibiting nitrification affects nitrogen cycle and reduces environmental impacts of anthropogenic nitrogen input}, volume={21}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.12802}, abstractNote={Abstract}, number={3}, journal={GLOBAL CHANGE BIOLOGY}, author={Qiao, Chunlian and Liu, Lingli and Hu, Shuijin and Compton, Jana E. and Greaver, Tara L. and Li, Quanlin}, year={2015}, month={Mar}, pages={1249–1257} }
 @article{jani_grossman_smyth_hu_2015, title={Influence of soil inorganic nitrogen and root diameter size on legume cover crop root decomposition and nitrogen release}, volume={393}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-015-2473-x}, number={1-2}, journal={PLANT AND SOIL}, author={Jani, Arun D. and Grossman, Julie M. and Smyth, Thomas J. and Hu, Shuijin}, year={2015}, month={Aug}, pages={57–68} }
 @article{chen_cheng_chu_hu_xie_tuvshintogtokh_bai_2015, title={Regional-scale patterns of soil microbes and nematodes across grasslands on the Mongolian plateau: relationships with climate, soil, and plants}, volume={38}, ISSN={["1600-0587"]}, DOI={10.1111/ecog.01226}, abstractNote={Belowground communities exert major controls over the carbon and nitrogen balances of terrestrial ecosystems by regulating decomposition and nutrient availability for plants. Yet little is known about the patterns of belowground communities and their relationships with environmental factors, particularly at the regional scale where multiple environmental gradients co‐vary. Here, we describe the patterns of belowground communities (microbes and nematodes) and their relationships with environmental factors based on two parallel studies: a field survey with two regional‐scale transects across the Mongolia plateau and a water‐addition experiment in a typical steppe. In the field survey, soils and plants were collected across two large‐scale transects (a 2000‐km east–west transect and a 900‐km south–north transect). At the regional‐scale, the variations in soil microbes (e.g. bacterial PLFA, fungal PLFA, and F/B ratio) were mainly explained by precipitation and soil factors. In contrast, the variation in soil nematodes (e.g. density of trophic groups and the bacterial‐feeding/fungal‐feeding nematode ratio) were primarily explained by precipitation. These variations of microbe or nematode variables explained by environmental factors at regional scale were derived from different vegetation types. Along the gradient from nutrient‐poor to nutrient‐rich vegetation types, the total variation in soil microbes explained by precipitation increased and that explained by plant and soil decreased, while the opposite was true for soil nematodes. Experimental water addition, which increased rainfall by 30% during the growing season, increased biomass or density of belowground communities, with the nematodes being more responsive than the microbes. The different responses of soil microbial and nematode communities to environmental gradients at the regional scale likely reflect their different adaptations to climate, soil nutrients, and plants. Our findings suggest that the soil nematode and microbial communities are strongly controlled by bottom‐up effects of precipitation alone or in combination with soil conditions.}, number={6}, journal={ECOGRAPHY}, author={Chen, Dima and Cheng, Junhui and Chu, Pengfei and Hu, Shuijin and Xie, Yichun and Tuvshintogtokh, Indree and Bai, Yongfei}, year={2015}, month={Jun}, pages={622–631} }
 @article{chandrasekaran_boughattas_hu_oh_sa_2014, title={A meta-analysis of arbuscular mycorrhizal effects on plants grown under salt stress}, volume={24}, ISSN={["1432-1890"]}, DOI={10.1007/s00572-014-0582-7}, abstractNote={Salt stress limits crop yield and sustainable agriculture in most arid and semiarid regions of the world. Arbuscular mycorrhizal fungi (AMF) are considered bio-ameliorators of soil salinity tolerance in plants. In evaluating AMF as significant predictors of mycorrhizal ecology, precise quantifiable changes in plant biomass and nutrient uptake under salt stress are crucial factors. Therefore, the objective of the present study was to analyze the magnitude of the effects of AMF inoculation on growth and nutrient uptake of plants under salt stress through meta-analyses. For this, data were compared in the context of mycorrhizal host plant species, plant family and functional group, herbaceous vs. woody plants, annual vs. perennial plants, and the level of salinity across 43 studies. Results indicate that, under saline conditions, AMF inoculation significantly increased total, shoot, and root biomass as well as phosphorous (P), nitrogen (N), and potassium (K) uptake. Activities of the antioxidant enzymes superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase also increased significantly in mycorrhizal compared to nonmycorrhizal plants growing under salt stress. In addition, sodium (Na) uptake decreased significantly in mycorrhizal plants, while changes in proline accumulation were not significant. Across most subsets of the data analysis, identities of AMF (Glomus fasciculatum) and host plants (Acacia nilotica, herbs, woody and perennial) were found to be essential in understanding plant responses to salinity stress. For the analyzed dataset, it is concluded that under salt stress, mycorrhizal plants have extensive root traits and mycorrhizal morphological traits which help the uptake of more P and K, together with the enhanced production of antioxidant enzymes resulting in salt stress alleviation and increased plant biomass.}, number={8}, journal={MYCORRHIZA}, author={Chandrasekaran, Murugesan and Boughattas, Sonia and Hu, Shuijin and Oh, Sang-Hyon and Sa, Tongmin}, year={2014}, month={Nov}, pages={611–625} }
 @article{yuan_tang_leng_hu_yong_chen_2014, title={An Invasive Plant Promotes Its Arbuscular Mycorrhizal Symbioses and Competitiveness through Its Secondary Metabolites: Indirect Evidence from Activated Carbon}, volume={9}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0097163}, abstractNote={Secondary metabolites released by invasive plants can increase their competitive ability by affecting native plants, herbivores, and pathogens at the invaded land. Whether these secondary metabolites affect the invasive plant itself, directly or indirectly through microorganisms, however, has not been well documented. Here we tested whether activated carbon (AC), a well-known absorbent for secondary metabolites, affect arbuscular mycorrhizal (AM) symbioses and competitive ability in an invasive plant. We conducted three experiments (experiments 1–3) with the invasive forb Solidago canadensis and the native Kummerowia striata. Experiment 1 determined whether AC altered soil properties, levels of the main secondary metabolites in the soil, plant growth, and AMF communities associated with S. canadensis and K. striata. Experiment 2 determined whether AC affected colonization of S. canadensis by five AMF, which were added to sterilized soil. Experiment 3 determined the competitive ability of S. canadensis in the presence and absence of AMF and AC. In experiment 1, AC greatly decreased the concentrations of the main secondary metabolites in soil, and the changes in concentrations were closely related with the changes of AMF in S. canadensis roots. In experiment 2, AC inhibited the AMF Glomus versiforme and G. geosporum but promoted G. mosseae and G. diaphanum in the soil and also in S. canadensis roots. In experiment 3, AC reduced S. canadensis competitive ability in the presence but not in the absence of AMF. Our results provided indirect evidence that the secondary metabolites (which can be absorbed by AC) of the invasive plant S. canadensis may promote S. canadensis competitiveness by enhancing its own AMF symbionts.}, number={5}, journal={PLOS ONE}, author={Yuan, Yongge and Tang, Jianjun and Leng, Dong and Hu, Shuijin and Yong, Jean W. H. and Chen, Xin}, year={2014}, month={May} }
 @article{lee_tu_chen_hu_2014, title={Arbuscular mycorrhizal fungi enhance P uptake and alter plant morphology in the invasive plant Microstegium vimineum}, volume={16}, ISSN={["1573-1464"]}, DOI={10.1007/s10530-013-0562-4}, number={5}, journal={BIOLOGICAL INVASIONS}, author={Lee, Marissa R. and Tu, Cong and Chen, Xin and Hu, Shuijin}, year={2014}, month={May}, pages={1083–1093} }
 @article{liu_jiang_hu_li_liu_wan_2014, title={Decoupling of soil microbes and plants with increasing anthropogenic nitrogen inputs in a temperate steppe}, volume={72}, DOI={10.1016/j.soilbio.2014.01.022}, abstractNote={Plant growth and soil microbial activity are intrinsically correlated. Numerous evidence shows that nitrogen (N) deposition can greatly alter both processes. However, it is unknown whether such changes caused by N deposition can create new dynamics between plants and soil microbes. This study was conducted with an attempt to examine the plant–microbe relationship along an N addition gradient. Eight levels of N addition (0, 1, 2, 4, 8, 16, 32, 64 g N m−2) were applied annually in a temperate steppe in northern China since 2003. Plant and soil samples were collected from 2005 to 2007. We found that N addition acidified soil significantly. Both plant aboveground biomass and dissolved organic carbon (DOC) increased with increasing N input. However, soil microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and (soil) microbial respiration showed nonlinear responses to N input. Low levels of N inputs stimulated MBC, MBN and microbial respiration, whereas high levels of N input suppressed them. Although MBC and MBN were both positively correlated with aboveground biomass at each level of N treatments, the dependence of such biomass on MBC and MBN declined with the increase in N addition, as indicated by the exponential decreases in the regression coefficients. The weakened linkage between aboveground biomass and MBC was mostly attributed to soil acidification. The decrease in soil pH caused by elevated N inputs reduced soil microbial activities, but not plant growth. Overall, our results revealed a trend of shifting plant–microbe relationship from coupling to decoupling with the increase of N input. The divergent responses of plants and soil microbial activities under intensified N addition could have consequent impacts on ecosystem function and services.}, journal={Soil Biology & Biochemistry}, author={Liu, W. X. and Jiang, L. and Hu, Shuijin and Li, L. H. and Liu, L. L. and Wan, S. Q.}, year={2014}, pages={116–122} }
 @article{zerpa_allen_mclaughlin_phelan_campbell_hu_2014, title={Postharvest forest floor manipulation effects on nutrient dynamics in a loblolly pine (Pinus taeda) plantation}, volume={44}, ISSN={["1208-6037"]}, DOI={10.1139/cjfr-2013-0536}, abstractNote={ The synchronization of nutrient release and demand in early stand establishment is important to maximizing resource use in forest plantations. We explored the impacts of forest floor manipulations on the dynamics of forest floor and mineral soil nutrient pools in a Pinus taeda L. plantation in North Carolina prior to and during 2 years following harvest and replanting. We present a novel method to estimate forest floor decomposition that avoids the exclusion of large detritivores. Decomposition and nutrient release rates from the forest floor were higher than rates typically observed in older stands (averaging 81% mass loss and 75% N loss across treatments over the 2-year period), highlighting the potential importance of the forest floor nutrient pool in early stand nutrition. Doubling the forest floor increased available C, N, and P pools in the mineral soil 46%, 47%, and 49%, respectively. Incorporating the forest floor into mineral soil through mixing had only transient positive effects on nutrient pools. Across treatments, an expected postharvest flush of soil available N was observed; however, removing the forest floor caused an earlier flush of available N in comparison with the control treatment, and doubling the forest floor caused a year delay in maximum N availability, better synchronizing the site’s available N with stand demand. }, number={9}, journal={CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE}, author={Zerpa, Jose L. and Allen, H. Lee and McLaughlin, Blair C. and Phelan, Jennifer and Campbell, Robert G. and Hu, Shuijin}, year={2014}, month={Sep}, pages={1058–1067} }
 @article{cheng_booker_burkey_tu_shew_rufty_fiscus_deforest_hu_2014, title={SOIL MICROBIAL RESPONSES TO ELEVATED CO2 AND O-3 IN A NITROGEN-AGGRADING AGROECOSYSTEM}, volume={6}, ISBN={["978-1-77188-021-3"]}, DOI={10.1371/journal.pone.0021377}, abstractNote={Climate change factors such as elevated atmospheric carbon dioxide (CO2) and ozone (O3) can exert significant impacts on soil microbes and the ecosystem level processes they mediate. However, the underlying mechanisms by which soil microbes respond to these environmental changes remain poorly understood. The prevailing hypothesis, which states that CO2- or O3-induced changes in carbon (C) availability dominate microbial responses, is primarily based on results from nitrogen (N)-limiting forests and grasslands. It remains largely unexplored how soil microbes respond to elevated CO2 and O3 in N-rich or N-aggrading systems, which severely hinders our ability to predict the long-term soil C dynamics in agroecosystems. Using a long-term field study conducted in a no-till wheat-soybean rotation system with open-top chambers, we showed that elevated CO2 but not O3 had a potent influence on soil microbes. Elevated CO2 (1.5×ambient) significantly increased, while O3 (1.4×ambient) reduced, aboveground (and presumably belowground) plant residue C and N inputs to soil. However, only elevated CO2 significantly affected soil microbial biomass, activities (namely heterotrophic respiration) and community composition. The enhancement of microbial biomass and activities by elevated CO2 largely occurred in the third and fourth years of the experiment and coincided with increased soil N availability, likely due to CO2-stimulation of symbiotic N2 fixation in soybean. Fungal biomass and the fungi∶bacteria ratio decreased under both ambient and elevated CO2 by the third year and also coincided with increased soil N availability; but they were significantly higher under elevated than ambient CO2. These results suggest that more attention should be directed towards assessing the impact of N availability on microbial activities and decomposition in projections of soil organic C balance in N-rich systems under future CO2 scenarios.}, number={6}, journal={CARBON CAPTURE AND STORAGE: CO2 MANAGEMENT TECHNOLOGIES}, author={Cheng, Lei and Booker, Fitzgerald L. and Burkey, Kent O. and Tu, Cong and Shew, H. David and Rufty, Thomas W. and Fiscus, Edwin L. and Deforest, Jared L. and Hu, Shuijin}, year={2014}, pages={277–307} }
 @article{yi_wen-xia_tu_washburn_lei_hu_2014, title={Soil Carbon, Nitrogen and Microbial Dynamics of Pasturelands: Impacts of Grazing Intensity and Planting Systems}, volume={24}, ISSN={["2210-5107"]}, DOI={10.1016/s1002-0160(14)60027-8}, abstractNote={Management intensity critically influences the productivity and sustainability of pasture systems through modifying soil microbes, and soil carbon (C) and nutrient dynamics; however, such effects are not well understood yet in the southeastern USA. We examined the effects of grazing intensity and grass planting system on soil C and nitrogen (N) dynamics, and microbial biomass and respiration in a long-term field experiment in Goldsboro, North Carolina, USA. A split-plot experiment was initiated in 2003 on a highly sandy soil under treatments of two grass planting systems (ryegrass rotation with sorghum-sudangrass hybrid and ryegrass seeding into a perennial bermudagrass stand) at low and high grazing densities. After 4 years of continuous treatments, soil total C and N contents across the 0–30 cm soil profile were 24.7% and 17.5% higher at the high than at the low grazing intensity, likely through promoting plant productivity and C allocation belowground as well as fecal and urinary inputs. Grass planting system effects were significant only at the low grazing intensity, with soil C, N, and microbial biomass and respiration in the top 10 cm being higher under the ryegrass/bermudagrass than under the ryegrass/sorghum-sudangrass hybrid planting systems. These results suggest that effective management could mitigate potential adverse effects of high grazing intensities on soil properties and facilitate sustainability of pastureland.}, number={3}, journal={PEDOSPHERE}, author={Yi, Wang and Wen-Xia, Duan and Tu, C. and Washburn, S. and Lei, Cheng and Hu, S.}, year={2014}, month={Jun}, pages={408–416} }
 @article{larsen_grossman_edgell_hoyt_osmond_hu_2014, title={Soil biological properties, soil losses and corn yield in long-term organic and conventional farming systems}, volume={139}, ISSN={["1879-3444"]}, DOI={10.1016/j.still.2014.02.002}, abstractNote={Topsoil losses through surface runoff have severe implications for farmers, as well as surrounding ecosystems and waterbodies. However, integrating management systems that enhance soil organic matter (SOM) can stabilize the soil surface from erosion. Little is known about how differences in both tillage and cropping system management affect carbon and subsequent sediment losses in horticultural fields, particularly in the humid climate of the southeast. Research was conducted in the Appalachian Mountains in Mills River, NC on a fine-sandy loam Acrisol from 2010 to 2012 on long-term plots established in 1994. Project objectives included to: (1) quantify labile and total organic matter based on tillage and cropping system practices, (2) determine if relationships exist between SOC ad sediment losses, and (3) determine long-term management and tillage impacts on total organic matter lost via runoff. We hypothesized that organic management and reduced tillage would lead to increased soil carbon, which subsequently reduce losses as soil is stabilized. Organic no tillage and conventional till treatments contained on average 14.34 and 6.80 g kg−1 total carbon (TC) respectively, with the organic no till treatments containing twice the quantity of TC and light fraction particulate organic matter (LPOM) in the upper 15 cm as compared with the conventionally tilled treatments, and four times the quantity of microbial biomass carbon (MBC). LPOM and HPOM, the heavier fraction of POM, did not differ in the organic till and conventional no till treatments.Data support our hypothesis that organic production in combination with no tillage increases C pools (both total and labile) as compared with tilled conventional plots. However, organic no till treatments produced sweet corn (Zea mays var. saccharata) yields less than 50% of that of conventional treatments, attributed to weed competition and lack of available N. No tillage treatments lost two to four times less soil C via surface runoff than tilled systems. Additionally, we found that as total soil C increased, suspended solids lost through surface runoff decreased. Overall, our results indicate tillage to be an important factor in enhancing soil C and decreasing soil loss through surface runoff.}, journal={SOIL & TILLAGE RESEARCH}, author={Larsen, Erika and Grossman, Julie and Edgell, Joshua and Hoyt, Greg and Osmond, Deanna and Hu, Shuijin}, year={2014}, month={Jun}, pages={37–45} }
 @article{cheng_booker_burkey_tu_shew_rufty_fiscus_deforest_hu_2014, title={Soil microbial responses to elevated CO2 and O-3 in a nitrogen-aggrading agroecosystem}, DOI={10.1201/b16845-14}, journal={Carbon Capture and Storage: CO2 Management Technologies}, author={Cheng, L. and Booker, F. L. and Burkey, K. O. and Tu, C. and Shew, H. D. and Rufty, T. W. and Fiscus, E. L. and Deforest, J. L. and Hu, Shuijin}, year={2014}, pages={277–307} }
 @article{rua_umbanhowar_hu_burkey_mitchell_2013, title={Elevated CO2 spurs reciprocal positive effects between a plant virus and an arbuscular mycorrhizal fungus}, volume={199}, ISSN={["1469-8137"]}, DOI={10.1111/nph.12273}, abstractNote={Summary}, number={2}, journal={NEW PHYTOLOGIST}, author={Rua, Megan A. and Umbanhowar, James and Hu, Shuijin and Burkey, Kent O. and Mitchell, Charles E.}, year={2013}, month={Jul}, pages={541–549} }
 @article{yuan_wang_zhang_tang_tu_hu_yong_chen_2013, title={Enhanced allelopathy and competitive ability of invasive plant Solidago canadensis in its introduced range}, volume={6}, ISSN={["1752-993X"]}, DOI={10.1093/jpe/rts033}, abstractNote={Aims Why invasive plants are more competitive in their introduced range than native range is still an unanswered question in plant invasion ecology. Here, we used the model invasive plant Solidago canaden- sis to test a hypothesis that enhanced production of allelopathic compounds results in greater competitive ability of invasive plants in the invaded range rather than in the native range. We also exam- ined the degree to which the allelopathy contributes increased com- petitive ability of S. canadensis in the invaded range. Methods We compared allelochemical production by S. canadensis growing in its native area (the USA) and invaded area (China) and also by populations that were collected from the two countries and grown together in a 'common garden' greenhouse experiment. We also tested the allelopathic effects of S. canadensis collected from either the USA or China on the germination of Kummerowia striata (a native plant in China). Finally, we conducted a common garden, greenhouse experiment in which K. striata was grown in monocul- ture or with S. canadensis from the USA or China to test the effects of allelopathy on plant-plant competition with suitable controls such}, number={3}, journal={JOURNAL OF PLANT ECOLOGY}, author={Yuan, Yongge and Wang, Bing and Zhang, Shanshan and Tang, Jianjun and Tu, Cong and Hu, Shuijin and Yong, Jean W. H. and Chen, Xin}, year={2013}, month={Jun}, pages={253–263} }
 @article{xie_xu_liu_liu_zhu_tu_amonette_cadisch_yong_hu_2013, title={Impact of biochar application on nitrogen nutrition of rice, greenhouse-gas emissions and soil organic carbon dynamics in two paddy soils of China}, volume={370}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-013-1636-x}, number={1-2}, journal={PLANT AND SOIL}, author={Xie, Zubin and Xu, Yanping and Liu, Gang and Liu, Qi and Zhu, Jianguo and Tu, Cong and Amonette, James E. and Cadisch, Georg and Yong, Jean W. H. and Hu, Shuijin}, year={2013}, month={Sep}, pages={527–540} }
 @article{cheng_booker_tu_burkey_zhou_shew_rufty_hu_2012, title={Arbuscular Mycorrhizal Fungi Increase Organic Carbon Decomposition Under Elevated CO2}, volume={337}, ISSN={["1095-9203"]}, DOI={10.1126/science.1224304}, abstractNote={A Fungal Culprit to Carbon Loss}, number={6098}, journal={SCIENCE}, author={Cheng, Lei and Booker, Fitzgerald L. and Tu, Cong and Burkey, Kent O. and Zhou, Lishi and Shew, H. David and Rufty, Thomas W. and Hu, Shuijin}, year={2012}, month={Aug}, pages={1084–1087} }
 @article{schroeder-moreno_greaver_wang_hu_rufty_2012, title={Mycorrhizal-mediated nitrogen acquisition in switchgrass under elevated temperatures and N enrichment}, volume={4}, ISSN={["1757-1707"]}, DOI={10.1111/j.1757-1707.2011.01128.x}, abstractNote={Abstract}, number={3}, journal={GLOBAL CHANGE BIOLOGY BIOENERGY}, author={Schroeder-Moreno, Michelle S. and Greaver, Tara L. and Wang, Shuxin and Hu, Shujin and Rufty, Thomas W.}, year={2012}, month={May}, pages={266–276} }
 @article{tu_wang_duan_hertl_tradway_brandenburg_lee_snell_hu_2011, title={Effects of fungicides and insecticides on feeding behavior and community dynamics of earthworms: Implications for casting control in turfgrass systems}, volume={47}, ISSN={0929-1393}, url={http://dx.doi.org/10.1016/j.apsoil.2010.11.002}, DOI={10.1016/j.apsoil.2010.11.002}, abstractNote={Earthworms play important roles in sustaining turfgrass systems through enhancing soil aeration, water filtration, and thatch mixing and decomposition. However, high surface activities of earthworms can lead to uneven playing surfaces, soil erosion and new niches favorable to weed invasion in the playing area of a golf course. Shifts from highly toxic and persistent to less toxic and easily degradable pesticides have been suggested to be largely responsible for high earthworm activities observed in turf systems worldwide. In this study, we examined the impact of fungicides and insecticides on earthworm behavior in controlled environments and on the dynamics of earthworm community in the field. Single application of insecticides Sevin (carbaryl) and Merit (imidacloprid) at the manufactures' suggested doses significantly inhibited earthworm feeding activity for at least three weeks without leading to any earthworm death. Fungicides did not show significant toxicity to earthworms when applied only once, but their toxicities increased as application frequency increased. Consecutive weekly applications of Sevin, Merit and T-methyl for four times led to earthworm mortality of 35, 45 and 80%, respectively. In the field, six consecutive weekly applications of T-methyl and Sevin significantly reduced the abundance and biomass of earthworms with suppressive effects lasting for at least 6 weeks after the chemical application was terminated. Taken together, these findings suggest that the surface activities of earthworms in turfgrass systems may be managed through moderate application of pesticides at peak periods of earthworm activities.}, number={1}, journal={Applied Soil Ecology}, publisher={Elsevier BV}, author={Tu, Cong and Wang, Yi and Duan, Wenxia and Hertl, Peter and Tradway, Lane and Brandenburg, Rick and Lee, David and Snell, Mark and Hu, Shuijin}, year={2011}, month={Jan}, pages={31–36} }
 @article{wang_tu_cheng_li_gentry_hoyt_zhang_hu_2011, title={Long-term impact of farming practices on soil organic carbon and nitrogen pools and microbial biomass and activity}, volume={117}, ISSN={["0167-1987"]}, DOI={10.1016/j.still.2011.08.002}, abstractNote={Conventional agriculture with intensive tillage and high inputs of synthetic chemicals has critically depleted the soil C pools. Alternative practices such as no-tillage and organic inputs have been shown to increase soil C content. However, the long-term impact of these practices on soil C pools was not fully understood under humid and warm climate conditions such as the southeast USA. We hypothesized that a combination of sustainable production practices will result in greater microbial biomass and activity and soil organic C than any individual practice. To test this hypothesis, we conducted a long-term experiment examining how different farming practices affect soil C and N pools and microbial biomass and activities in a fine-sandy loam (FAO: Acrisol) in the southern Appalachian mountains of North Carolina, USA. The experiment was a randomized complete design with four replications. Six management treatments, i.e., tillage with no chemical or organic inputs (Control, TN), tillage with chemical inputs (TC), tillage with organic inputs (TO), no-tillage with chemical inputs (NC), no-tillage with organic inputs (NO), and fescue grasses (FG), were designed. Organic C and N pools and microbial properties in 0–15 cm soils were markedly different after 15 years of continuous treatments. Both no tillage and organic inputs significantly promoted soil microbial biomass by 63–139% and 54–126%; also microbial activity increased by 88–158% and 52–117%, respectively. Corresponding increases of soil organic C by 83–104% and 19–32%, and soil organic N by 77–94% and 20–32% were measured. The combination of no tillage and organic management increased soil organic C by 140% over the conventional tillage control, leading to a soil C content comparable to an un-disturbed grassland control. No tillage reduced the proportion of organic C in the light fraction with d < 1.0 g cm−3 (from 1.53–3.39% to 0.80–1.09%), and increased the very heavy fraction with d > 1.6 g cm−3 (from 95% to 98%). Organic inputs, however, had little impact on C distribution among different density fractions of the soil except light fraction in tillage treatment. Over all, no-tillage practices exerted greater influence on microbial biomass levels and activity and soil organic C levels and fractionations than organic inputs. Our results support the hypothesis and indicate that management decisions including reducing tillage and increasing organic C inputs can enhance transformation of soil organic C from the labile into stable pools, promote soil C accumulation, improve soil fertility and while mitigate atmospheric CO2 rise.}, journal={SOIL & TILLAGE RESEARCH}, author={Wang, Yi and Tu, Cong and Cheng, Lei and Li, Chunyue and Gentry, Laura F. and Hoyt, Greg D. and Zhang, Xingchang and Hu, Shuijin}, year={2011}, month={Dec}, pages={8–16} }
 @article{cheng_zhu_chen_zheng_oh_rufty_richter_hu_2010, title={Atmospheric CO2 enrichment facilitates cation release from soil}, volume={13}, ISSN={["1461-0248"]}, DOI={10.1111/j.1461-0248.2009.01421.x}, abstractNote={ Ecology Letters (2010) 13: 284–291}, number={3}, journal={ECOLOGY LETTERS}, author={Cheng, L. and Zhu, J. and Chen, G. and Zheng, X. and Oh, N. -H. and Rufty, T. W. and Richter, D. deB and Hu, S.}, year={2010}, month={Mar}, pages={284–291} }
 @article{zhang_jin_zhu_tang_hu_zhou_chen_2010, title={Baicalin Released from Scutellaria baicalensis Induces Autotoxicity and Promotes Soilborn Pathogens}, volume={36}, ISSN={["1573-1561"]}, DOI={10.1007/s10886-010-9760-z}, abstractNote={Experiments were conducted to determine whether allelochemicals released by the important medicinal plant Scutellaria baicalensis Georgi help to explain why S. baicalensis performs poorly when continuously cropped. Based on high performance liquid chromatography, the concentration of baicalin (the major compound released by S. baicalensis roots) in the soil where S. baicalensi had been grown for 3 years was 0.97 microg x g(-1). Both the crude extracts from S. baicalensis roots and purified baicalin at 0.97 microg x g(-1) increased the mortality of S. baicalensis seedlings in an autotoxicity test. This concentration stimulated the growth of two soilborne pathogens (Pythium ultimum and Rhizoctonia solani) on agar, and their growth and pathogenic activity in sand. Seedling mortality and damping-off caused by both pathogens were greater in sand where S. canadensis had previously grown than in sand where it had not previously grown. Mortality and damping-off of S. baicalensis seedlings also were significantly higher in soil collected from an S. baicalensis field than in soil collected from a Nicotiana tabacum L. field. The results are consistent with the hypothesis that allelochemicals released by S. baicalensis negatively affect S. baicalensis directly by inducing autotoxicity and indirectly by increasing pathogen activity in the soil.}, number={3}, journal={JOURNAL OF CHEMICAL ECOLOGY}, author={Zhang, Shanshan and Jin, Yili and Zhu, Wenjie and Tang, Jianjun and Hu, Shuijin and Zhou, Tongshui and Chen, Xin}, year={2010}, month={Mar}, pages={329–338} }
 @article{zhang_yang_tang_yang_hu_chen_2010, title={Positive Feedback between Mycorrhizal Fungi and Plants Influences Plant Invasion Success and Resistance to Invasion}, volume={5}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0012380}, abstractNote={Negative or positive feedback between arbuscular mycorrhizal fungi (AMF) and host plants can contribute to plant species interactions, but how this feedback affects plant invasion or resistance to invasion is not well known. Here we tested how alterations in AMF community induced by an invasive plant species generate feedback to the invasive plant itself and affect subsequent interactions between the invasive species and its native neighbors. We first examined the effects of the invasive forb Solidago canadensis L. on AMF communities comprising five different AMF species. We then examined the effects of the altered AMF community on mutualisms formed with the native legume forb species Kummerowia striata (Thunb.) Schindl. and on the interaction between the invasive and native plants. The host preferences of the five AMF were also assessed to test whether the AMF form preferred mutualistic relations with the invasive and/or the native species. We found that S. canadensis altered AMF spore composition by increasing one AMF species (Glomus geosporum) while reducing Glomus mosseae, which is the dominant species in the field. The host preference test showed that S. canadensis had promoted the abundance of AMF species (G. geosporum) that most promoted its own growth. As a consequence, the altered AMF community enhanced the competitiveness of invasive S. canadensis at the expense of K. striata. Our results demonstrate that the invasive S. canadensis alters soil AMF community composition because of fungal-host preference. This change in the composition of the AMF community generates positive feedback to the invasive S. canadensis itself and decreases AM associations with native K. striata, thereby making the native K. striata less dominant.}, number={8}, journal={PLOS ONE}, author={Zhang, Qian and Yang, Ruyi and Tang, Jianjun and Yang, Haishui and Hu, Shuijin and Chen, Xin}, year={2010}, month={Aug} }
 @article{sydorovych_raczkowski_wossink_mueller_creamer_hu_bell_tu_2009, title={A technique for assessing environmental impact risks of agricultural systems}, volume={24}, ISSN={["1742-1713"]}, DOI={10.1017/S174217050999010X}, abstractNote={Abstract}, number={3}, journal={RENEWABLE AGRICULTURE AND FOOD SYSTEMS}, author={Sydorovych, Olha and Raczkowski, Charles W. and Wossink, Ada and Mueller, J. Paul and Creamer, Nancy G. and Hu, Shuijin and Bell, Melissa and Tu, Cong}, year={2009}, month={Sep}, pages={234–243} }
 @article{tu_booker_burkey_hu_2009, title={Elevated Atmospheric Carbon Dioxide and O-3 Differentially Alter Nitrogen Acquisition in Peanut}, volume={49}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2008.10.0603}, abstractNote={ABSTRACT}, number={5}, journal={CROP SCIENCE}, author={Tu, Cong and Booker, Fitzgerald L. and Burkey, Kent O. and Hu, Shuijin}, year={2009}, pages={1827–1836} }
 @article{liu_king_booker_giardina_allen_hu_2009, title={Enhanced litter input rather than changes in litter chemistry drive soil carbon and nitrogen cycles under elevated CO2: a microcosm study}, volume={15}, ISSN={["1365-2486"]}, DOI={10.1111/j.1365-2486.2008.01747.x}, abstractNote={Abstract}, number={2}, journal={GLOBAL CHANGE BIOLOGY}, author={Liu, Lingli and King, John S. and Booker, Fitzgerald L. and Giardina, Christian P. and Allen, H. Lee and Hu, Shuijin}, year={2009}, month={Feb}, pages={441–453} }
 @article{tang_xu_chen_hu_2009, title={Interaction between C-4 barnyard grass and C-3 upland rice under elevated CO2: Impact of mycorrhizae}, volume={35}, ISSN={["1873-6238"]}, DOI={10.1016/j.actao.2008.10.005}, abstractNote={Atmospheric CO2 enrichment may impact arbuscular mycorrhizae (AM) development and function, which could have subsequent effects on host plant species interactions by differentially affecting plant nutrient acquisition. However, direct evidence illustrating this scenario is limited. We examined how elevated CO2 affects plant growth and whether mycorrhizae mediate interactions between C4 barnyard grass (Echinochloa crusgalli (L.) Beauv.) and C3 upland rice (Oryza sativa L.) in a low nutrient soil. The monocultures and combinations with or without mycorrhizal inoculation were grown at ambient (400 ± 20 μmol mol−1) and elevated CO2 (700 ± 20 μmol mol−1) levels. The 15N isotope tracer was introduced to quantify the mycorrhizally mediated N acquisition of plants. Elevated CO2 stimulated the growth of C3 upland rice but not that of C4 barnyard grass under monoculture. Elevated CO2 also increased mycorrhizal colonization of C4 barnyard grass but did not affect mycorrhizal colonization of C3 upland rice. Mycorrhizal inoculation increased the shoot biomass ratio of C4 barnyard grass to C3 upland rice under both CO2 concentrations but had a greater impact under the elevated than ambient CO2 level. Mycorrhizae decreased relative interaction index (RII) of C3 plants under both ambient and elevated CO2, but mycorrhizae increased RII of C4 plants only under elevated CO2. Elevated CO2 and mycorrhizal inoculation enhanced 15N and total N and P uptake of C4 barnyard grass in mixture but had no effects on N and P acquisition of C3 upland rice, thus altering the distribution of N and P between the species in mixture. These results implied that CO2 stimulation of mycorrhizae and their nutrient acquisition may impact competitive interaction of C4 barnyard grass and C3 upland rice under future CO2 scenarios.}, number={2}, journal={ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY}, author={Tang, Jianjun and Xu, Liming and Chen, Xin and Hu, Shuijin}, year={2009}, pages={227–235} }
 @article{liu_gumpertz_hu_ristaino_2008, title={Effect of prior tillage and soil fertility amendments on dispersal of Phytophthora capsici and infection of pepper}, volume={120}, ISSN={["1573-8469"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-38649084121&partnerID=MN8TOARS}, DOI={10.1007/s10658-007-9216-7}, number={3}, journal={EUROPEAN JOURNAL OF PLANT PATHOLOGY}, author={Liu, Bo and Gumpertz, Marcia L. and Hu, Shuijin and Ristaino, Jean Beagle}, year={2008}, month={Mar}, pages={273–287} }
 @article{shao_wang_dean_lin_gao_hu_2008, title={Expression of a harpin-encoding gene in rice confers durable nonspecific resistance to Magnaporthe grisea}, volume={6}, ISSN={["1467-7644"]}, DOI={10.1111/j.1467-7652.2007.00304.x}, abstractNote={Summary}, number={1}, journal={PLANT BIOTECHNOLOGY JOURNAL}, author={Shao, Min and Wang, Jinsheng and Dean, Ralph A. and Lin, Yongjun and Gao, Xuewen and Hu, Shuijin}, year={2008}, month={Jan}, pages={73–81} }
 @article{wang_liu_wang_gong_hua_pang_hu_yang_2008, title={Impacts of methamidophos on the biochemical, catabolic, and genetic characteristics of soil microbial communities}, volume={40}, ISSN={["0038-0717"]}, DOI={10.1016/j.soilbio.2007.10.012}, abstractNote={Methamidophos is an organophosphate pesticide with high toxicity and may significantly affect soil microbes. However, the magnitude of this effect is unclear. We examined the effect of low and high inputs of methamidophos on the structure of the soil microbial community, and the catabolic activity and the genetic diversity of the bacterial community using the polyphasic approaches of microbial biomass, phospholipid fatty acids (PLFAs), community-level catabolic profiles (CLCPs), and amplified ribosomal DNA restriction analysis (ARDRA) patterns. Our results indicated that high methamidophos inputs significantly reduced total microbial biomass carbon (Cmic) and fungal biomass, but increased Gram-negative bacteria with no significant effects on the Gram-positive bacteria. Interestingly, CLCPs patterns showed that high methamidophos inputs also significantly improved the catabolic activity of Gram-negative bacteria. The ARDRA pattern showed that the genetic diversity of the bacterial community decreased under chemical stress. Furthermore, changes in the microbial parameters examined were less significant under low inputs than high inputs of methamidophos, suggesting a dosage effect of methamidophos on the microbial community. Our results provide the first evidence that methamidophos differentially affected components of the soil microbial community through inhibiting fungal growth but enhancing the biomass and catabolic activity of Gram-negative bacteria.}, number={3}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Wang, Meng-Cheng and Liu, Ye-Hao and Wang, Qiong and Gong, Ming and Hua, Xiao-Mei and Pang, Yan-Jun and Hu, Shuijin and Yang, Yong-Hua}, year={2008}, month={Mar}, pages={778–788} }
 @article{liu_tu_hu_gumpertz_ristaino_2007, title={Effect of organnic, sustainable, and conventional management strategies in grower fields on soil physical, chemical, and biological factors and the incidence of Southern blight}, volume={37}, ISSN={["1873-0272"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-34748831003&partnerID=MN8TOARS}, DOI={10.1016/j.apsoil.2007.06.007}, abstractNote={The objectives of our research were to evaluate the impact of organic, sustainable, and conventional management strategies in grower fields on soil physical, chemical, and biological factors including soil microbial species and functional diversity and their effect on the Basidiomycete plant pathogen Sclerotium rolfsii, causal agent of Southern blight. Soils from 10 field locations including conventional, organic and sustainable farms were sampled and assayed for disease suppressiveness in greenhouse assays, and soil quality indicators. Soils from organic and sustainable farms were more suppressive to Southern blight than soils from conventional farms. Soils from organic farms had improved soil chemical factors and higher levels of extractable C and N, higher microbial biomass carbon and nitrogen, and net mineralizable N. In addition, soil microbial respiration was higher in soils from organic than sustainable or conventional farms, indicating that microbial activity was greater in these soils. Populations of fungi and thermophiles were significantly higher in soils from organic and sustainable than conventional fields. The diversity of bacterial functional communities was also greater in soils from organic farms, while species diversity was similar. Soils from organic and sustainable farms had improved soil health as indicated by a number of soil physical, chemical and biological factors and reduced disease.}, number={3}, journal={APPLIED SOIL ECOLOGY}, author={Liu, Bo and Tu, Cong and Hu, Shuijin and Gumpertz, Marcia and Ristaino, Jean Beagle}, year={2007}, month={Nov}, pages={202–214} }
 @article{yang_tang_chen_hu_2007, title={Effects of coexisting plant species on soil microbes and soil enzymes in metal lead contaminated soils}, volume={37}, ISSN={["1873-0272"]}, DOI={10.1016/j.apsoil.2007.07.004}, abstractNote={It is not clear whether plant species coexistence can offset the impacts of heavy metal lead (Pb) on soil microbes and soil enzyme activities. We conducted a factorial experiment to investigate the effects of three plant species combinations (1, 2 and 4 species) on soil microbial and soil enzyme properties under three Pb concentrations (0, 300 and 600 mg kg−1 soil). Microbial biomass carbon (MBC), BIOLOG profiles of soil microbes and soil enzyme activities were measured. Under monoculture, elevated Pb did not reduce soil MBC, had no effects on activities of urease, acid phosphatase and dehydrogenase, but stimulated the activity of alkaline phosphatase. Compared to monoculture, plant species coexistence did not significantly affect soil microbial biomass C but increased microbial functional group diversity index and urease activity under different Pb concentrations. In addition, microbial community structure diverged among plant coexistence treatments under each Pb concentration. These results suggested that coexistence of plant species might alleviate the effects of metal lead on soil microbes and reducing metal lead effect on urease activity.}, number={3}, journal={APPLIED SOIL ECOLOGY}, author={Yang, Ruyi and Tang, Jianjun and Chen, Xin and Hu, Shuijin}, year={2007}, month={Nov}, pages={240–246} }
 @article{liu_gumpertz_hu_ristaino_2007, title={Long-term effects of organic and synthetic soil fertility amendments on soil microbial communities and the development of southern blight}, volume={39}, ISSN={["1879-3428"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-34250215285&partnerID=MN8TOARS}, DOI={10.1016/j.soilbio.2007.04.001}, abstractNote={The effects of tillage and soil fertility amendments on the relationship between the suppressiveness of soils to southern blight and soil physical, chemical and biological factors were examined in experimental station plots in North Carolina. Main plots were either tilled frequently or surface-mulched after one initial tillage. Organic soil amendments including composted cotton gin trash, composted poultry manure, an incorporated rye–vetch green manure, or synthetic fertilizer were applied to subplots in a split-plot design experiment. Incidence of southern blight was lower in surfaced-mulched than tilled soils. Incidence of southern blight was also lower in soils amended with cotton gin trash than those amended with poultry manure, rye–vetch green manure or synthetic fertilizer. Soil water content was negatively correlated with the incidence of disease in both years. Disease incidence was negatively correlated with the level of potassium, calcium, cation exchange capacity (CEC), base saturation (BS) and humic matter in 2002, and net mineralizable nitrogen in 2001. Although, populations of thermophilic organisms were significantly higher in soils amended with cotton gin trash than the other three fertility amendments in each year, there was no significant correlation between the populations of thermophiles and incidence of the disease. Bacterial community diversity indices based on community-level physiological profiling (CLPP) and denaturing gradient gel electrophoresis (DGGE) were significantly higher in soils amended with cotton gin trash than those amended with poultry manure, green manure or synthetic fertilizer. There was a significant negative correlation between the incidence of southern blight, and CLPP and DGGE diversity indices. Greater differences in the richness of bacterial functional groups than genotypes were observed. These results demonstrate that organic soil fertility amendments and cotton gin trash in particular, reduced the development of the disease and affected soil physical, chemical and biological parameters.}, number={9}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Liu, Bo and Gumpertz, Marcia L. and Hu, Shuijin and Ristaino, Jean Beagle}, year={2007}, month={Sep}, pages={2302–2316} }
 @article{chen_tu_burton_watson_burkey_hu_2007, title={Plant nitrogen acquisition and interactions under elevated carbon dioxide: impact of endophytes and mycorrhizae}, volume={13}, ISSN={["1365-2486"]}, DOI={10.1111/j.1365-2486.2007.01347.x}, abstractNote={Abstract}, number={6}, journal={GLOBAL CHANGE BIOLOGY}, author={Chen, Xin and Tu, Cong and Burton, Michael G. and Watson, Dorothy M. and Burkey, Kent O. and Hu, Shuijin}, year={2007}, month={Jun}, pages={1238–1249} }
 @article{tu_booker_watson_chen_rufty_shi_hu_2006, title={Mycorrhizal mediation of plant N acquisition and residue decomposition: Impact of mineral N inputs}, volume={12}, ISSN={["1365-2486"]}, DOI={10.1111/j.1365-2486.2006.01149.x}, abstractNote={Abstract}, number={5}, journal={GLOBAL CHANGE BIOLOGY}, author={Tu, C and Booker, FL and Watson, DM and Chen, X and Rufty, TW and Shi, W and Hu, SJ}, year={2006}, month={May}, pages={793–803} }
 @article{hu_tu_chen_gruver_2006, title={Progressive N limitation of plant response to elevated CO2: a microbiological perspective}, volume={289}, ISSN={["0032-079X"]}, DOI={10.1007/s11104-006-9093-4}, number={1-2}, journal={PLANT AND SOIL}, author={Hu, Shuijin and Tu, Cong and Chen, Xin and Gruver, Joel B.}, year={2006}, month={Nov}, pages={47–58} }
 @article{tu_louws_creamer_mueller_brownie_fager_bell_hu_2006, title={Responses of soil microbial biomass and N availability to transition strategies from conventional to organic farming systems}, volume={113}, ISSN={["1873-2305"]}, DOI={10.1016/j.agee.2005.09.013}, abstractNote={Abstract Organic farming can enhance soil biodiversity, alleviate environmental concerns and improve food safety through eliminating the applications of synthetic chemicals. However, yield reduction due to nutrient limitation and pest incidence in the early stages of transition from conventional to organic systems is a major concern for organic farmers, and is thus a barrier to implementing the practice of organic farming. Therefore, identifying transition strategies that minimize yield loss is critical for facilitating the implementation of organic practices. Soil microorganisms play a dominant role in nutrient cycling and pest control in organic farming systems, and their responses to changes in soil management practices may critically impact crop growth and yield. Here we examined soil microbial biomass and N supply in response to several strategies for transitioning from conventional to organic farming systems in a long-term field experiment in Goldsboro, NC, USA. The transitional strategies included one fully organic strategy (ORG) and four reduced-input strategies (withdrawal of each or gradual reduction of major conventional inputs—synthetic fertilizers, pesticides (insecticides/fungicides), and herbicides), with a conventional practice (CNV) serving as a control. Microbial biomass and respiration rate were more sensitive to changes in soil management practices than total C and N. In the first 2 years, the ORG was most effective in enhancing soil microbial biomass C and N among the transition strategies, but was accompanied with high yield losses. By the third year, soil microbial biomass C and N in the reduced-input transition strategies were statistically significantly greater than those in the CNV (averaging 32 and 35% higher, respectively), although they were slightly lower than those in the ORG (averaging 13 and 17% lower, respectively). Soil microbial respiration rate and net N mineralization in all transitional systems were statistically significantly higher than those in the CNV (averagely 83 and 66% greater, respectively), with no differences among the various transition strategies. These findings suggest that the transitional strategies that partially or gradually reduce conventional inputs can serve as alternatives that could potentially minimize economic hardships as well as benefit microbial growth during the early stages of transition to organic farming systems.}, number={1-4}, journal={AGRICULTURE ECOSYSTEMS & ENVIRONMENT}, author={Tu, C and Louws, FJ and Creamer, NG and Mueller, JP and Brownie, C and Fager, K and Bell, M and Hu, SJ}, year={2006}, month={Apr}, pages={206–215} }
 @article{tu_ristaino_hu_2006, title={Soil microbial biomass and activity in organic tomato farming systems: Effects of organic inputs and straw mulching}, volume={38}, ISSN={["1879-3428"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-29744443972&partnerID=MN8TOARS}, DOI={10.1016/j.soilbio.2005.05.002}, abstractNote={Organic farming is rapidly expanding worldwide. Plant growth in organic systems greatly depends on the functions performed by soil microbes, particularly in nutrient supply. However, the linkages between soil microbes and nutrient availability in organically managed soils are not well understood. We conducted a long-term field experiment to examine microbial biomass and activity, and nutrient availability under four management regimes with different organic inputs. The experiment was initiated in 1997 by employing different practices of organic farming in a coastal sandy soil in Clinton, NC, USA. Organic practices were designed by applying organic substrates with different C and N availability, either in the presence or absence of wheat–straw mulch. The organic substrates used included composted cotton gin trash (CGT), animal manure (AM) and rye/vetch green manure (RV). A commercial synthetic fertilizer (SF) was used as a conventional control. Results obtained in both 2001 and 2002 showed that microbial biomass and microbial activity were generally higher in organically than conventionally managed soils with CGT being most effective. The CGT additions increased soil microbial biomass C and activity by 103–151% and 88–170% over a period of two years, respectively, leading to a 182–285% increase in potentially mineralizable N, compared to the SF control. Straw mulching further enhanced microbial biomass, activity, and potential N availability by 42, 64, and 30%, respectively, relative to non-mulched soils, likely via improving C and water availability for soil microbes. The findings that microbial properties and N availability for plants differed under different organic input regimes suggest the need for effective residue managements in organic tomato farming systems.}, number={2}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Tu, C and Ristaino, JB and Hu, SJ}, year={2006}, month={Feb}, pages={247–255} }
 @article{chen_wu_tang_hu_2005, title={Arbuscular mycorrhizae enhance metal lead uptake and growth of host plants under a sand culture experiment}, volume={60}, ISSN={["1879-1298"]}, DOI={10.1016/j.chemosphere.2005.01.029}, abstractNote={A sand culture experiment was conducted to investigate whether mycorrhizal colonization and mycorrhizal fungal vesicular numbers were influenced by metal lead, and whether mycorrhizae enhance host plants tolerance to metal lead. Metal lead was applied as Pb(NO3)2 in solution at three levels (0, 300 and 600 mg kg(-1) sand). Five mycorrhizal host plant species, Kummerowia striata (Thunb.) Schindl, Ixeris denticulate L., Lolium perenne L., Trifolium repens L. and Echinochloa crusgalli var. mitis were used to examine Pb-mycorrhizal interactions. The arbuscular mycorrhizal inoculum consisted of mixed spores of mycorrhizal fungal species directly isolated from orchard soil. Compared to the untreated control, both Pb concentrations reduced mycorrhizal colonization by 3.8-70.4%. Numbers of AM fungal vesicles increased by 13.2-51.5% in 300 mg Pb kg(-1) sand but decreased by 9.4-50.9% in 600 mg Pb kg(-1) sand. Mycorrhizae significantly enhanced Pb accumulation both in shoot by 10.2-85.5% and in root by 9.3-118.4%. Mycorrhizae also enhanced shoot biomass and shoot P concentration under both Pb concentrations. Root/shoot ratios of Pb concentration were higher in highly mycorrhizal plant species (K.striata, I. denticulate, and E. crusgalli var. mitis) than that in poorly mycorrhizal ones (L. perenne and T. repens,). Mycorrhizal inoculation increased the root/shoot ratio of Pb concentration of highly mycorrhizal plant species by 7.6-57.2% but did not affect the poorly mycorrhizal ones. In the treatments with 300 Pb mg kg(-1) sand, plant species with higher vesicular numbers tended to show higher root/shoot ratios of the Pb concentration. We suggest that under an elevated Pb condition, mycorrhizae could promote plant growth by increasing P uptake and mitigate Pb toxicity by sequestrating more Pb in roots.}, number={5}, journal={CHEMOSPHERE}, author={Chen, X and Wu, CH and Tang, JJ and Hu, SJ}, year={2005}, month={Jul}, pages={665–671} }
 @article{chen_tang_zhi_hu_2005, title={Arbuscular mycorrhizal colonization and phosphorus acquisition of plants: effects of coexisting plant species}, volume={28}, ISSN={["1873-0272"]}, DOI={10.1016/j.apsoil.2004.07.009}, abstractNote={Arbuscular mycorrhizal (AM) fungi influence interactions among plant species through enhancing nutrient uptake and possibly facilitating nutrient transport among plants. However, the effects of one plant species on coexisting plant species with regard to mycorrhizal colonization are not well understood. We examined root mycorrhizal colonization and phosphorus (P) acquisition of plants in a highly P-limiting soil in Lanxi city, Zhejiang, China from the year 2000 to 2002. Three dominant native plant species with different mycorrhizal properties, Digitaria ciliaris (poorly mycorrhizal species), Ixeris denticulate (moderately mycorrhizal species) and Kummerowia striata (highly mycorrhizal species), were planted in experimental plots. In the monocultures, K. striata was found to have the highest infection and D. ciliaris the lowest mycorrhizal infection, but shoot P-concentration was higher in both I. denticulate and D. ciliaris than that in K. striata. In the mixtures, D. ciliaris and I. denticulate did not significantly affect the mycorrhizal colonization, spore production and shoot P-concentration of K. striata plants, but K. striata and I. denticulate significantly increased root mycorrhizal colonization and shoot P-concentration of D. ciliaris. K. striata enhanced but D. ciliaris reduced mycorrhizal infection and shoot P-concentration of I. denticulate. These results suggested that highly mycorrhizal plant species may positively impact coexisting species with respect to mycorrhizal colonization and P acquisition, but the effects on poorly mycorrhizal species are less predictable.}, number={3}, journal={APPLIED SOIL ECOLOGY}, author={Chen, X and Tang, JJ and Zhi, GY and Hu, SJ}, year={2005}, month={Mar}, pages={259–269} }
 @article{booker_prior_torbert_fiscus_pursley_hu_2005, title={Decomposition of soybean grown under elevated concentrations of CO2 and O-3}, volume={11}, DOI={10.1111/j.1365.2486.2005.00939.x}, number={4}, journal={Global Change Biology}, author={Booker, F. L. and Prior, S. A. and Torbert, H. A. and Fiscus, E. L. and Pursley, W. A. and Hu, Shuijin}, year={2005}, pages={685–698} }
 @article{hu_wu_burkey_firestone_2005, title={Plant and microbial N acquisition under elevated atmospheric CO2 in two mesocosm experiments with annual grasses}, volume={11}, ISSN={["1365-2486"]}, DOI={10.1111/j.1365-2486.2005.00905.x}, abstractNote={Abstract}, number={2}, journal={GLOBAL CHANGE BIOLOGY}, author={Hu, SJ and Wu, JS and Burkey, KO and Firestone, MK}, year={2005}, month={Feb}, pages={213–223} }
 @article{zhang_rui_tu_diab_louws_mueller_creamer_bell_wagger_hu_2005, title={Responses of soil microbial community structure and diversity to agricultural deintensification}, volume={15}, number={4}, journal={Pedosphere}, author={Zhang, W. J. and Rui, W. Y. and Tu, C. and Diab, H. G. and Louws, F. J. and Mueller, J. P. and Creamer, N. and Bell, M. and Wagger, M. G. and Hu, S.}, year={2005}, pages={440–447} }
 @article{zhang_parker_luo_wan_wallace_hu_2005, title={Soil microbial responses to experimental warming and clipping in a tallgrass prairie}, volume={11}, ISSN={["1365-2486"]}, DOI={10.1111/j.1365-2486.2005.00902.x}, abstractNote={Abstract}, number={2}, journal={GLOBAL CHANGE BIOLOGY}, author={Zhang, W and Parker, KM and Luo, Y and Wan, S and Wallace, LL and Hu, S}, year={2005}, month={Feb}, pages={266–277} }
 @article{zhang_zhu_hu_2005, title={Soil resource availability impacts microbial response to organic carbon and inorganic nitrogen inputs}, volume={17}, number={5}, journal={Journal of Environmental Sciences (China)}, author={Zhang, W. J. and Zhu, W. and Hu, S.}, year={2005}, pages={705–710} }
 @article{hu_weijian_2004, title={Impact of global change on biological processes in soil: Implications for agroecosystem management}, volume={12}, ISBN={1542-7528}, DOI={10.1300/j411v12n01_02}, abstractNote={SUMMARY The Earth is undergoing rapid environmental changes due to human activities. Three components of the ongoing global change, elevated atmospheric CO2, N deposition, and global warming, may significantly impact soil biota directly through modifying the physical and chemical environment, and indirectly through altering aboveground plant growth and community composition. The biomass, community structure, and activities of microbes and animals in soil as well as their interactions will likely be affected, leading to changes in ecological processes and functions. Biological processes that may be modified by global change include organic matter decomposition, N mineralization, food web interaction, and biotic N fixation. Lack of the complexity in agroecosystems may amplify the effects of global change on many biological processes in agricultural soils. However, minimizing human disturbance and thus increasing the complexity of agroecosystems may enhance the potential of C sequestration in agricultural soils and the stability of belowground systems, thereby contributing to ecological sustainability.}, number={1}, journal={Journal of Crop Improvement}, author={Hu, Shuijin and WeiJian, Zhang}, year={2004}, pages={289} }
 @article{tu_koenning_hu_2003, title={Root-parasitic nematodes enhance soil microbial activities and nitrogen mineralization}, volume={46}, ISSN={["1432-184X"]}, DOI={10.1007/s00248-002-1068-2}, abstractNote={Obligate root-parasitic nematodes can affect soil microbes positively by enhancing C and nutrient leakage from roots but negatively by restricting total root growth. However, it is unclear how the resulting changes in C availability affect soil microbial activities and N cycling. In a microplot experiment, effects of root-parasitic reniform nematodes ( Rotylenchulus reniformis) on soil microbial biomass and activities were examined in six different soils planted with cotton. Rotylenchulus reniformis was introduced at 900 nematodes kg(-1) soil in May 2000 prior to seeding cotton. In 2001, soil samples were collected in May before cotton was seeded and in November at the final harvest. Extractable C and N were consistently higher in the R. reniformis treatments than in the non-nematode controls across the six different soils. Nematode inoculation significantly reduced microbial biomass C, but increased microbial biomass N, leading to marked decreases in microbial biomass C:N ratios. Soil microbial respiration and net N mineralization rates were also consistently higher in the nematode treatments than in the controls. However, soil types did not have a significant impact on the effects of nematodes on these microbial parameters. These findings indicate that nematode infection of plant roots may enhance microbial activities and the turnover of soil microbial biomass, facilitating soil N cycling. The present study provides the first evidence about the direct role of root-feeding nematodes in enhancing soil N mineralization.}, number={1}, journal={MICROBIAL ECOLOGY}, author={Tu, C and Koenning, SR and Hu, S}, year={2003}, month={Jul}, pages={134–144} }
 @article{diab_hu_benson_2003, title={Suppression of Rhizoctonia solani on impatiens by enhanced microbial activity in composted swine waste-amended potting mixes}, volume={93}, ISSN={["0031-949X"]}, DOI={10.1094/PHYTO.2003.93.9.1115}, abstractNote={ Peat moss-based potting mix was amended with either of two composted swine wastes, CSW1 and CSW2, at rates from 4 to 20% (vol/vol) to evaluate suppression of pre-emergence damping-off of impatiens (Impatiens balsamina) caused by Rhizoctonia solani (anastomosis group-4). A cucumber bioassay was used prior to each impatiens experiment to monitor maturity of compost as the compost aged in a curing pile by evaluating disease suppression toward both Pythium ultimum and R. solani. At 16, 24, 32, and 37 weeks after composting, plug trays filled with compost-amended potting mix were seeded with impatiens and infested with R. solani to determine suppression of damping-off. Pre-emergence damping-off was lower for impatiens grown in potting mix amended with 20% CSW1 than in CSW2-amended and nonamended mixes. To identify relationships between disease suppression and microbial parameters, samples of mixes were collected to determine microbial activity, biomass carbon and nitrogen, functional diversity, and population density. Higher rates of microbial activity were observed with increasing rates of CSW1 amendment than with CSW2 amendments. Microbial biomass carbon and nitrogen also were higher in CSW1-amended mixes than in CSW2-amended potting mixes 1 day prior to seeding and 5 weeks after seeding. Principal component analysis of Biolog-GN2 profiles showed different functional diversities between CSW1- and CSW2-amended mixes. Furthermore, mixes amended with CSW1 had higher colony forming units of fungi, endospore-forming bacteria, and oligotrophic bacteria. Our results suggest that enhanced microbial activity, functional and population diversity of stable compost-amended mix were associated with suppressiveness to Rhizoctonia damping-off in impatiens. }, number={9}, journal={PHYTOPATHOLOGY}, author={Diab, HG and Hu, S and Benson, DM}, year={2003}, month={Sep}, pages={1115–1123} }
 @article{mueller_barbercheck_bell_brownie_creamer_hitt_hu_king_linker_louws_et al._2002, title={Development and implementation of a long-term agricultural systems study: Challenges and opportunities}, volume={12}, number={3}, journal={HortTechnology}, author={Mueller, J. P. and Barbercheck, M. E. and Bell, M. and Brownie, C. and Creamer, N. G. and Hitt, A. and Hu, S. and King, L. and Linker, H. M. and Louws, F. J. and et al.}, year={2002}, pages={362–368} }
 @article{hu_chapin_firestone_field_chiariello_2001, title={Nitrogen limitation of microbial decomposition in a grassland under elevated CO2}, volume={409}, ISSN={["0028-0836"]}, DOI={10.1038/35051576}, abstractNote={Carbon accumulation in the terrestrial biosphere could partially offset the effects of anthropogenic CO2 emissions on atmospheric CO2. The net impact of increased CO2 on the carbon balance of terrestrial ecosystems is unclear, however, because elevated CO2 effects on carbon input to soils and plant use of water and nutrients often have contrasting effects on microbial processes. Here we show suppression of microbial decomposition in an annual grassland after continuous exposure to increased CO2 for five growing seasons. The increased CO2 enhanced plant nitrogen uptake, microbial biomass carbon, and available carbon for microbes. But it reduced available soil nitrogen, exacerbated nitrogen constraints on microbes, and reduced microbial respiration per unit biomass. These results indicate that increased CO2 can alter the interaction between plants and microbes in favour of plant utilization of nitrogen, thereby slowing microbial decomposition and increasing ecosystem carbon accumulation.}, number={6817}, journal={NATURE}, author={Hu, S and Chapin, FS and Firestone, MK and Field, CB and Chiariello, NR}, year={2001}, month={Jan}, pages={188–191} }