TY - CONF TI - Robotic imaging-based methods for leaf segmentation and growth tracking in Arabidopsis AU - Xiang, L. AU - Bao, Y. AU - Nolan, T. AU - Yin, Y. AU - Tang, L. T2 - 2019 ASABE Annual International Meeting C2 - 2019/// C3 - 2019 ASABE Annual International Meeting CY - Boston, MA DA - 2019/// PY - 2019/7/7/ ER - TY - JOUR TI - Automated morphological traits extraction for sorghum plants via 3D point cloud data analysis AU - Xiang, Lirong AU - Bao, Yin AU - Tang, Lie AU - Ortiz, Diego AU - Salas-Fernandez, Maria G. T2 - Computers and Electronics in Agriculture AB - The ability to correlate morphological traits of plants with their genotypes plays an important role in plant phenomics research. However, measuring phenotypes manually is time-consuming, labor intensive, and prone to human errors. The 3D surface model of a plant can potentially provide an efficient and accurate way to digitize plant architecture. This study focused on the extraction of morphological traits at multiple developmental timepoints from sorghum plants grown under controlled conditions. A non-destructive 3D scanning system using a commodity depth camera was implemented to capture sequential images of a plant at different heights. To overcome the challenges of overlapping tillers, an algorithm was developed to first search for the stem in the merged point cloud data, and then the associated leaves. A 3D skeletonization algorithm was created by slicing the point cloud along the vertical direction, and then linking the connected Euclidean clusters between adjacent layers. Based on the structural clues of the sorghum plant, heuristic rules were implemented to separate overlapping tillers. Finally, each individual leaf was automatically segmented, and multiple parameters were obtained from the skeleton and the reconstructed point cloud including: plant height, stem diameter, leaf angle, and leaf surface area. The results showed high correlations between the manual measurements and the estimated values generated by the system. Statistical analyses between biomass and extracted traits revealed that stem volume was a promising predictor of shoot fresh weight and shoot dry weight, and the total leaf area was strongly correlated to shoot biomass at early stages. DA - 2019/7// PY - 2019/7// DO - 10.1016/j.compag.2019.05.043 VL - 162 SP - 951-961 J2 - Computers and Electronics in Agriculture LA - en OP - SN - 0168-1699 UR - http://dx.doi.org/10.1016/j.compag.2019.05.043 DB - Crossref ER - TY - CONF TI - Antimicrobial Resistance of Salmonella Recovered from Environmental Samples on Three North Carolina Tomato Farms AU - Moore, R.G. AU - Ducharme, D.T. AU - Burris, K.P. AU - Simmons, O.D., III AU - Jaykus, L.A. AU - Zheng, J. AU - Brown, E. AU - Bell, R.L. T2 - International Association for Food Protection Annual Meeting C2 - 2019/// CY - Louisville, KY DA - 2019/// PY - 2019/7/21/ ER - TY - CONF TI - Prevalence and Fitness of Produce Outbreak Associated Salmonella enterica in Tomato Plants AU - Burris, K.P. AU - Simmons, O.D., III AU - Webb, H.M. AU - Moore, R.G. AU - Jaykus, L.A. AU - Zheng, J. AU - Reed, E. AU - Brown, E. AU - Bell, R.L. T2 - International Association for Food Protection C2 - 2019/// CY - Louisville, KY DA - 2019/// PY - 2019/7/21/ ER - TY - RPRT TI - Natural and Constructed Wetlands in North Carolina: An Overview for Citizens AU - Burchell, Michael AU - Hunt, Bill A3 - North Carolina Cooperative Extension Publication DA - 2019/2/19/ PY - 2019/2/19/ M1 - AG-856 M3 - NC State Extension Publications PB - North Carolina Cooperative Extension Publication SN - AG-856 UR - https://content.ces.ncsu.edu/natural-and-constructed-wetlands-in-north-carolina ER - TY - JOUR TI - DRAINMOD-based tools for quantifying reductions in annual drainage flow and nitrate losses resulting from drainage water management on croplands in eastern North Carolina (vol 166, pg 86, 2016) AU - Negm, L. M. AU - Youssef, M. A. AU - Chescheir, G. M. AU - Skaggs, R. W. T2 - AGRICULTURAL WATER MANAGEMENT DA - 2019/12/20/ PY - 2019/12/20/ DO - 10.1016/j.agwat.2019.105811 VL - 226 SP - SN - 1873-2283 ER - TY - JOUR TI - Farmer harvest decisions and vegetable loss in primary production AU - Johnson, Lisa K. AU - Bloom, J. Dara AU - Dunning, Rebecca D. AU - Gunter, Chris C. AU - Boyette, Michael D. AU - Creamer, Nancy G. T2 - AGRICULTURAL SYSTEMS AB - The topic of food loss and waste has risen in importance since the revelation that an estimated 40% of food in America is never consumed. Losses at the field level, however, are not well understood, and economic and growing conditions that dictate decisions made by fruit and vegetable growers can determine how much food is left unharvested. Many strategies have been suggested to reduce food loss and waste, but their development has been informed by concerns at the consumer level, and may not motivate growers to reduce losses. This study sought to understand how growers make decisions regarding when to end the harvest, and explores growers' perceptions of strategies that would incentivize them to reduce losses. The authors conducted seventeen semi-structured interviews with mid-sized to large commercial vegetable growers in North Carolina. The resulting findings clarify the primary decision-making drivers affecting food loss in the field, including whether growers have an interested buyer, the quality of the produce, the available price, the financial risk of product rejection, and the priority of another field becoming mature and ready to harvest. Growers did not perceive losses to be of high enough volume or value to measure crops that were left unharvested in the field, though research indicates that the volume is actually significant. We also asked growers about their perceptions of strategies for reducing farm level losses that have been promoted in industry reports on the subject. These strategies include facilitating donation and supporting emerging markets that focus on imperfect produce. Neither of these aligned well with strategies that growers perceived as important, such as increasing demand, providing processing infrastructure, and facilitating a consistent market and prices. While some growers donate produce or participate in gleaning, these activities can be limited by continued negative perceptions. Findings from this research suggest that, in order to effectively reduce the loss of edible food at the farm level, growers must be included in the development of strategies, and those strategies must incentivize their participation in order to be effective. DA - 2019/11// PY - 2019/11// DO - 10.1016/j.agsy.2019.102672 VL - 176 SP - SN - 1873-2267 KW - Food waste KW - Food loss KW - Primary production KW - Interviews KW - Farmers KW - Vegetable crops ER - TY - JOUR TI - NUTRIENT EXPORT FROM AGRICULTURAL WATERSHEDS IN THE PIEDMONT AND COASTAL PLAIN, NORTH CAROLINA AU - Line, D. E. AU - Osmond, D. L. AU - Childres, W. T2 - TRANSACTIONS OF THE ASABE AB - Abstract. Nitrogen (N) and phosphorus (P) input and export rates were determined in six rural, predominantly agricultural watersheds located in the Piedmont and Coastal Plain regions of North Carolina. Water quality monitoring was conducted at the outlets for 2.3 to 8.0 years to determine the annual N and P export from each watershed. Total N and P input and export from five of the six watersheds were correlated, with only a no-till cropland watershed differing. The correlation showed that N and P exports increased by about 4.0% and 8.7%, respectively, of applied N and P for the range of applications rates, whereas dissolved N (NO x -N) export increased by 2.8% with increasing N application rates. Therefore, practices that reduce inputs, such as nutrient management, should result in similar percentage reductions in exports. The Small Watershed Nutrient Forecasting Tool (SWIFT) was used to forecast discharge, N, P, and sediment export from each of the six watersheds. For the no-till cropland watershed, the SWIFT-forecasted N and P export rates were more than 2.5 times those measured, while the sediment export rate was 72 times the measured value. Thus, these data showed that the SWIFT forecasts for N, P, and sediment export were poor for the no-till cropland watershed. For the pasture watershed, the SWIFT forecasts for N and sediment export agreed reasonably well with measured export; however, the forecasted P export was much less than measured. For the four mixed land use watersheds, the SWIFT forecasts for discharge, TN, and sediment were mostly greater than measured, and the forecasted TP export was less than measured for three of the four watersheds. Thus, as with many predicstion tools, SWIFT results must be used with caution. Keywords: Nutrient export, Nutrient management practice, Water quality monitoring. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13052 VL - 62 IS - 5 SP - 1135-1145 SN - 2151-0040 KW - Nutrient export KW - Nutrient management practice KW - Water quality monitoring ER - TY - JOUR TI - COMPARISON OF HYDROLOGY OF TWO ATLANTIC COASTAL PLAIN FORESTS AU - Amatya, D. M. AU - Williams, T. M. AU - Nettles, J. E. AU - Skaggs, R. W. AU - Trettin, C. C. T2 - TRANSACTIONS OF THE ASABE AB - Abstract. This article compares the short-term and long-term hydrology of two typical forests in the humid Atlantic Coastal Plain, including a relatively undisturbed forest with natural drainage in South Carolina (SC) and a drained pine plantation in North Carolina (NC), using monitoring and modeling approaches. Highly dynamic outflow (O) from both of these systems is driven by the water table (WT) position, as influenced by rainfall (R) and evapotranspiration (ET). The annual runoff coefficient (ROC) varied from 5% in dry years to 56% in wet years, depending on the soil water storage (SWS), with a significantly higher average value for the NC site despite its deeper WT, on average, than the SC site. Although both sites behaved similarly in extreme climate conditions, the change in SWS above the WT influenced the annual RO, ROC, and ET. The 17-year average annual ET of 1114 mm (R – O, assuming annual balanced SWS) for the SC site was significantly higher (p = 0.014) than the ET of the drained NC site (997 mm) despite the SC site’s lower mean annual R of 1370 mm, compared to 1520 mm for the NC site. This may be due to both the higher potential ET (PET) and soil water-holding capacity of the SC site. The SC site had higher frequency and duration of WT near the surface during winter, deeper summer WT, and higher correlation of annual ET to annual R (r 2 = 0.90 vs. 0.15), suggesting that the SC site was often moisture-limited, particularly during the growing season. Most of the streamflow in these systems occurred during winter, with low ET demands. However, summer periods with tropical storms also resulted in large RO events, generally with higher frequency and longer durations at the drained NC site. These results are similar to an earlier short-term comparison with an unstable behavior period at the SC site after Hurricane Hugo (1989). This study highlighted (1) the differences in hydrology between coastal forests drained for silvicultural production and undrained natural forests managed only for restoration, (2) the importance of long-term monitoring and the effects of regeneration as well as vegetation management on flow regime, and (3) the application and limitations of two widely used models (MIKESHE and DRAINMOD) in describing the hydrology of these forests. Long-term studies can be a basis for testing new hypotheses on water yield, stormwater management, wetland hydrology, vegetation restoration, bioenergy production, and climate change, in addition to applications of proper models for assessing the eco-hydrologic impacts of land use and climate change on freshwater coastal forests linked with downstream riparian rivers and estuaries affected by tidal fluxes and sea level rise. Highlights Outflow, driven by water table position on these forest systems, is highly variable, depending on its soil water storage. The hydrologic responses of both forest sites were similar during extreme climatic events or disturbances. Effect of forestry drainage on runoff was obscured by its large interannual differences. Long-term monitoring provides better insights on climate and vegetation management effects on flow regime and model validation Keywords: Drainage, Evapotranspiration, Hydrologic models, Pine forest, Poorly drained soils, Runoff coefficient, Water table. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13387 VL - 62 IS - 6 SP - 1509-1529 SN - 2151-0040 KW - Drainage KW - Evapotranspiration KW - Hydrologic models KW - Pine forest KW - Poorly drained soils KW - Runoff coefficient KW - Water table ER - TY - JOUR TI - EFFECTS OF FORMIC AND LEVULINIC ACIDS ON BUTYRIC ACID SYNTHESIS BY CLOSTRIDIUM TYROBUTYRICUM IN XYLOSE MEDIA AU - Liu, Y. AU - Geng, Y. AU - Zhao, R. AU - Zheng, H. AU - Yuan, W. T2 - TRANSACTIONS OF THE ASABE AB - Abstract. Weak acids released during hydrolysis of lignocellulosic biomass are potential inhibitors of microorganism fermentation. In this study, the effects of formic and levulinic acids on butyric acid synthesis by were investigated. With the addition of 1.2 to 4.8 g L -1 of formic acid, increased lag time, decreased cell density, and lower butyric acid productivity were observed. Up to 15% and 56% reduction in peak cell density and butyric acid productivity, respectively, were caused by formic acid addition, whereas there was no significant difference in butyric acid yield between the control and formic acid treated groups (except for the 2.4 g formic acid L -1 treatment). Levulinic acid did not show any notable effects on within the investigated concentration range (0 to 4.8 g L -1 ). Overall, showed strong tolerance of both formic and levulinic acids, but neither of these acids could be metabolized by the microbe. Highlights Formic acid had dosage-dependent inhibitory effects on C. tyrobutyricum. Levulinic acid had no effects on cell growth or butyrate synthesis. Neither formic acid nor levulinic acid was metabolized by C. tyrobutyricum. C. tyrobutyricum showed strong tolerance to formic acid and levulinic acid. Keywords: Butyric acid, Clostridium tyrobutyricum, Formic acid, Levulinic acid, Lignocellulosic hydrolysate, Xylose. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13669 VL - 62 IS - 6 SP - 1803-1809 SN - 2151-0040 KW - Butyric acid KW - Clostridium tyrobutyricum KW - Formic acid KW - Levulinic acid KW - Lignocellulosic hydrolysate KW - Xylose ER - TY - JOUR TI - Storm Event Nitrogen Dynamics in Waterfowl Impoundments AU - Hinckley, B. R. AU - Etheridge, J. R. AU - Peralta, A. L. T2 - WATER AIR AND SOIL POLLUTION AB - Waterfowl impoundments are hydrologically managed to provide food and habitat for migratory birds and have the potential to export nitrogen during drawdown. The goal of this study was to describe how nitrate, ammonium, and dissolved organic nitrogen dynamics varied under two different management schemes during storm events. This was made possible through monitoring the three forms of nitrogen at a high frequency (30 min) in a moist-soil managed (MSM) impoundment and seasonally flooded agricultural impoundment (Ag) for 17 months. Substantial differences in nitrogen dynamics between sites were observed when the sites were not flooded, while similar dynamics were observed during the winter flooding period. When the Ag site was drained, storm events mobilized nitrate (average 0.3 mg L−1; increase 0.8 mg L−1) and ammonium (average 0.4 mg L−1; increase 0.2 mg L−1). Under drained conditions in the MSM impoundment, rainfall reduced ammonium (average 0.5 mg L−1; decrease 0.1 mg L−1). Storms stimulated what appeared to be coupled nitrification-denitrification in both impoundments when flooded and ammonium concentrations were elevated. A surprising result of this work was observed at the Ag site, where elevated nitrate (0.5 mg L−1) was measured during high water levels when anoxic conditions were expected to support denitrification. Although water management schemes were found to be important for controlling nitrogen dynamics, other factors, such as carbon quality, require further research. This study demonstrates a high variability between storm events and the large influence of hydrologic management schemes on nitrogen dynamics during storm events. DA - 2019/12// PY - 2019/12// DO - 10.1007/s11270-019-4332-5 VL - 230 IS - 12 SP - SN - 1573-2932 KW - Waterfowl impoundments KW - Nitrogen KW - Storm events KW - Biogeochemistry ER - TY - JOUR TI - Process-Based Design Strengthens the Analysis of Stream and Floodplain Systems under a Changing Climate AU - Fox, Garey A. T2 - Transactions of the ASABE AB - Highlights Stream-riparian interactions and preferential flow remain two “unsolved” problems in hydrology. Using mechanistic approaches enables analysis of stream and floodplain systems under future climatic extremes. Engineers should verify stream restoration designs with models that consider stream-riparian interactions. Riparian buffer design models should consider preferential flow and be more widely used for site-specific design. Keywords: . Climate Variability, Floodplain, Preferential flow, Process-based design, Riparian buffer, Stream restoration, Streambank erosion, Vegetative Filter Strip. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13594 VL - 62 IS - 6 SP - 1735–1742 SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13594 KW - Climate Variability KW - Floodplain KW - Preferential flow KW - Process-based design KW - Riparian buffer KW - Stream restoration KW - Streambank erosion KW - Vegetative Filter Strip ER - TY - JOUR TI - The Potential Resiliency of a Created Tidal Marsh to Sea Level Rise AU - Kamrath, Brock J. W. AU - Burchell, Michael R. AU - Cormier, Nicole AU - Krauss, Ken W. AU - Johnson, Darren J. T2 - Transactions of the ASABE AB - Abstract. The purpose of this study was to determine the elevation dynamics of a created tidal marsh on the North Carolina coast. Deep rod surface elevation tables (RSET) and feldspar marker horizons (MH) were installed in plots to measure net surface elevation changes and to quantify contributing processes. Twelve total plots were placed on four elevation gradient transects (three transects within the created marsh and one within a reference marsh), with three plots along each transect. Elevation gradient transects included a low marsh plot dominated by , a middle marsh plot dominated by , and a high marsh plot dominated by . RSET and MH were measured in December 2012, January 2014, April 2017, and March 2018. Elevation change ranged from 1.0 to 4.0 mm year -1 within the created marsh and from -0.4 to 2.0 mm year -1 within the reference marsh. When compared to the long-term linear trend in local relative sea level rise (RSLR) of 3.10 ±0.35 mm year -1 , the middle marsh plots within the created marsh trended toward survival, with an observed elevation increase of 3.1 ±0.2 mm year -1 . Alternatively, the low and high marsh plots within the created marsh trended toward submergence, with observed elevation increases of 2.1 ±0.2 and 1.3 ±0.2 mm year -1 , respectively. These results indicate that a created marsh can display elevation dynamics similar to a natural marsh and can be resilient to current rates of RSLR if constructed with a high elevation capital. Surface elevation changes were observed over a short time period and in a relatively young marsh, so it is uncertain if these trends will continue or how the long-term relation with RSLR will develop. While this study provided initial data on the ability of created tidal marshes to respond to observed sea level rise, subsequent observations are needed to evaluate the long-term elevation dynamics. Keywords: Resiliency, Sea level rise, Surface elevation tables, Tidal marsh, Vertical accretion. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13438 VL - 62 IS - 6 SP - 1567-1577 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13438 DB - Crossref KW - Resiliency KW - Sea level rise KW - Surface elevation tables KW - Tidal marsh KW - Vertical accretion ER - TY - JOUR TI - The Potential Long-Term Impacts of Climate Change on the Hydrologic Regimes of North Carolina’s Coastal Plain Non-Riverine Wetlands AU - Kurki-Fox, J. Jack AU - Burchell, Michael R. AU - Kamrath, Brock J. T2 - Transactions of the ASABE AB - Highlights Based on current emissions, mean water table decline in these wetlands will likely range from 25 to 65 cm by 2100. Projected changes could lead to a decline or loss of the important ecosystem services that wetlands provide to society. Results indicate a potential need to allocate more resources to developing strategies for managing wetlands. Abstract. Wetlands are especially at risk from climate change because of their intermediate landscape position (i.e., transition between upland and aquatic environments), where small changes in precipitation and/or evapotranspiration can have substantial impacts on wetland hydrology. Because hydrology is the primary factor influencing wetland structure and function, the important ecosystem services that wetlands provide may be altered or lost as a result of climate change. While a great deal of uncertainty is associated with the projected impacts of climate change on wetlands, hydrologic models and downscaled climate model projections provide tools to reduce this uncertainty. DRAINMOD is one such process-based hydrologic model that has been successfully adapted to simulate the daily water level fluctuations in natural wetlands. The objective of this project was to determine the range of possible impacts of climate change on the hydrologic regimes of non-riverine, non-tidal Coastal Plain wetlands in North Carolina. DRAINMOD models were calibrated and validated for two minimally disturbed, natural wetland sites using observed water table and local weather data. Two representative concentration pathway (RCP) scenarios were evaluated: RCP4.5 and RCP8.5. Nine models were selected from an ensemble of 32 climate models to represent the range of possible changes in mean precipitation and temperature. Downscaled climate projections were obtained from the U.S. Bureau of Reclamation. Simulations were run from 1986 to 2099, and results were evaluated by comparing the projected mean water table levels between the base period (1986-2015) and two future evaluation periods: 2040-2069 and 2070-2099. The model simulation results indicated that the projected mean water table level may decline by as much as 25 to 84 cm by the end of this century (2070-2099) for the RCP8.5 scenario and may decline by 4 to 61 cm for the RCP4.5 scenario. In Coastal Plain wetlands, declines in water tables can lead to the subsidence of organic soils, which can lead to the loss of stored carbon and increased risk of peat fires. Lower mean water levels can also lead to shifts in vegetation community composition and loss of habitat functions for wetland-dependent fauna. These results provide an overview of the potential impacts of climate change on North Carolina wetlands, and they provide a range of scenarios to inform and guide possible changes to water management strategies in wetland ecosystems that can be implemented now to limit the loss of ecosystem services over the long term. Keywords: Climate change, DRAINMOD, Hydrology, Modeling, North Carolina, Wetlands. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13437 VL - 62 IS - 6 SP - 1591-1606 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13437 DB - Crossref ER - TY - JOUR TI - Navigating the Publication Process: An ASABE Journals’ Perspective AU - Fox, Garey A. AU - Douglas-Mankin, Kyle R. AU - Muthukumarappan, Kasiviswanathan AU - Zhu, Jun AU - Walker, Joseph C. T2 - Transactions of the ASABE AB - Abstract. Highlights ASABE journals publish impactful research in multiple article types in addition to research articles. Prospective authors should consider a journal’s peer-review quality, readership, metrics, and page charges. An article’s impact should be measured based on citations instead of predicted based on the journal’s impact factor. Always recommend subject matter experts as reviewers so that a manuscript can benefit from their suggestions. Publishing in ASABE journals offers opportunities for contributing to and being recognized by the profession. Keywords: Impact factor, Page charges, Peer-reviewed journals, Review quality, Review time DA - 2019/// PY - 2019/// DO - 10.13031/trans.13648 VL - 62 IS - 5 SP - 1147-1153 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13648 DB - Crossref KW - Impact factor KW - Page charges KW - Peer-reviewed journals KW - Review quality KW - Review time ER - TY - JOUR TI - Wetland Ecosystem Resilience: Protecting and Restoring Valuable Ecosystems AU - Messer, T.L. AU - Douglas-Mankin, K.R. AU - Nelson, N.G. AU - Etheridge, J.R. T2 - Transactions of the ASABE AB - Highlights We provide context and perspectives on articles in the Wetland Ecosystem Resilience collection. Insights gained on wetland resilience to sea-level rise and climate change, land use and drainage, and nutrients. Abstract. The objective of this article is to introduce a collection of articles that explore current research and scientific thought on wetland ecosystem resilience. The collection contains articles on wetland resilience to climate change, agricultural land use-driven change, and recreational land use, along with evaluations of wetland resilience through high-resolution monitoring and modeling tools. Wetland settings in the U.S. span tidal marshes and coastal plain non-riverine wetlands in North Carolina, prairie potholes in Iowa, Appalachian floodplain wetlands, and floating treatment wetlands in the Midwest. The studies in this collection found vertical accretion rates of 0.7 to 4.0 mm year -1 in a tidal marsh, a wide range of potential wetland hydroperiod responses to climate change, substantial decreases in inundation period, crop yield, and surface-water nitrate (but increases in phosphorus) in artificially drained potholes, and nitrate removal in carbon-amended floating treatment wetlands. Further work is needed to better understand how to design and enhance wetland systems in agricultural regions, better preserve wetland ecosystem services in areas affected by land use and climate change, and provide technical standards for the wide range of designs currently used for wetland treatment systems. Keywords: Agricultural wetlands, Resiliency, Temporal data, Treatment wetlands, Water chemistry, Water quality, Water treatment DA - 2019/// PY - 2019/// DO - 10.13031/trans.13578 VL - 62 IS - 6 SP - 1541-1543 UR - http://dx.doi.org/10.13031/trans.13578 KW - Agricultural wetlands KW - Resiliency KW - Temporal data KW - Treatment wetlands KW - Water chemistry KW - Water quality KW - Water treatment ER - TY - JOUR TI - Windbreak Wall-vegetative Strip System to Reduce Air Emissions from Mechanically-Ventilated Livestock Barns – Part 1: CFD Modeling AU - Ajami, Ali AU - Shah, Sanjay B. AU - Stikeleather, Larry F. T2 - Water, Air, & Soil Pollution DA - 2019/12// PY - 2019/12// DO - 10.1007/s11270-019-4333-4 VL - 230 IS - 12 J2 - Water Air Soil Pollut LA - en OP - SN - 0049-6979 1573-2932 UR - http://dx.doi.org/10.1007/s11270-019-4333-4 DB - Crossref KW - Backpressure KW - Airflow rate KW - Airspeed KW - Porosity KW - Slant wall fan KW - Swine KW - Poultry ER - TY - JOUR TI - Design and field evaluation of a ground robot for high-throughput phenotyping of energy sorghum AU - Young, Sierra N. AU - Kayacan, Erkan AU - Peschel, Joshua M. T2 - Precision Agriculture AB - This article describes the design and field evaluation of a low-cost, high-throughput phenotyping robot for energy sorghum for use in biofuel production. High-throughput phenotyping approaches have been used in isolated growth chambers or greenhouses, but there is a growing need for field-based, precision agriculture techniques to measure large quantities of plants at high spatial and temporal resolutions throughout a growing season. A low-cost, tracked mobile robot was developed to collect phenotypic data for individual plants and tested on two separate energy sorghum fields in Central Illinois during summer 2016. Stereo imaging techniques determined plant height, and a depth sensor measured stem width near the base of the plant. A data capture rate of 0.4 ha, bi-weekly, was demonstrated for platform robustness consistent with various environmental conditions and crop yield modeling needs, and formative human–robot interaction observations were made during the field trials to address usability. This work is of interest to researchers and practitioners advancing the field of plant breeding because it demonstrates a new phenotyping platform that can measure individual plant architecture traits accurately (absolute measurement error at 15% for plant height and 13% for stem width) over large areas at a sub-daily frequency; furthermore, the design of this platform can be extended for phenotyping applications in maize or other agricultural row crops. DA - 2019/8/15/ PY - 2019/8/15/ DO - 10.1007/s11119-018-9601-6 VL - 20 IS - 4 SP - 697-722 UR - https://doi.org/10.1007/s11119-018-9601-6 KW - Agricultural robotics KW - Field-based phenotyping KW - Plant imaging KW - Sorghum ER - TY - JOUR TI - A Response to "Reanalysis Validates Soil Health Indicator Sensitivity and Correlation with Long-term Crop Yields" AU - Roper, Wayne R. AU - Osmond, Deanna L. AU - Heitman, Joshua L. T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - We published data showing that current soil health indicator (SHI) assessments do not consistently detect differences in a range of soil management practices implemented in North Carolina soils. Van Es and Karlen reanalyzed our data and asserted that it validates SHI correlation to crop yields and sensitivity to management as measured by the Comprehensive Assessment of Soil Health (CASH). We respond to van Es and Karlen with a more representative analysis of our data showing that individual SHI measurements are not predictive of crop yield from the 30‐yr North Carolina agronomic trial. Regressions for aggregate stability ( r 2 = 0.07) and P ( r 2 = 0.18) show that neither SHI sufficiently predicts corn yield for this dataset and show no obvious pattern based on tillage intensity. Relationships between corn ( Zea mays L.) yield and most biological SHI had r 2 ≤ 0.18, with only soil protein being moderately predictive of corn yield ( r 2 = 0.45). The CASH index to assess overall soil health by integrating physical, chemical, and biological SHI measurements into a single value of soil health is also not predictive of corn yield in the trial ( r 2 = 0.12). It is possible that current sampling and analytical procedures for assessing soil health do not consistently detect differences in productivity from soils with regional differences in land and ecological resources. We believe that calibrating SHI assessments to quantifiable agroecological outcomes instead of statistical rankings will reduce bias across regions and create a more inclusive framework for quantifying soil health. DA - 2019/// PY - 2019/// DO - 10.2136/sssaj2019.06.0198 VL - 83 IS - 6 SP - 1842-1845 SN - 1435-0661 ER - TY - JOUR TI - Valorization of Eggshell Waste into Supported Copper Catalysts for Partial Oxidation of Methane AU - Karoshi, Gourishankar AU - Kolar, Praveen AU - Shah, Sanjay AU - Gilleskie, Gary T2 - INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH DA - 2019/// PY - 2019/// DO - 10.1007/s41742-019-00238-0 KW - Eggshell KW - Copper KW - Catalyst KW - Methane KW - Partial oxidation ER - TY - BOOK TI - Solid State Fermentation: Research and Industrial Applications AU - Werner, Anett AU - Steudler, Susanne AU - Cheng, Jay AB - This book offers an authoritative review of the main challenges, processes, products and applications of solid state fermentation. They range from enzyme production to the production of antibiotics and pigments to the use in environmental technology and energy production. DA - 2019/// PY - 2019/// DO - 10.1007/978-3-030-23675-5 VL - 169 SE - 1-172 SN - 978-3-030-23674-8 ER - TY - JOUR TI - Revisiting the sampling, sample preparation, and analytical variability associated with testing wheat for deoxynivalenol AU - Tittlemier, S. A. AU - Chan, J. AU - Gaba, D. AU - Pleskach, K. AU - Osborne, J. AU - Slate, A. B. AU - Whitaker, T. B. T2 - WORLD MYCOTOXIN JOURNAL AB - Fifteen lots of wheat were sampled to characterise the total variance and distribution among sample test results associated with measuring deoxynivalenol (DON) in bulk wheat lots. An unbalanced nested experimental design based on past research was used to determine contributions to the total variance from sampling, sample preparation, and analysis. The wheat lots used in the study contained average DON concentrations that ranged from 0.17 to 24.5 mg/kg. Sampling was determined to be the largest contributor to the total variance of measuring DON at low mg/kg concentrations, which are relevant to existing maximum levels. With the experimental design parameters of 1 kg laboratory samples, sub-division of whole and ground grain using rotary sample division, sample comminution using a commercial-grade coffee grinder, extraction of 100 g test portions, and making one measurement of DON in the test portion by gas chromatography-mass spectrometry, the total variance of DON measurement at 2 mg/kg was 0.046 mg 2 /kg 2 (coefficient of variation=10.7%). At this concentration, sampling contributed 67% to the total variance, followed by sample preparation (18%) and analysis (15%). The DON distribution among sample test results was accurately described by the normal distribution. The mathematical model of variance was used with the normal distribution of DON measurement results to construct operating characteristics curves to model the likelihood of mischaracterising a wheat lot as (non) compliant with a certain decision limit. With realistic laboratory sample and test portion sizes, as well as a practicable decision limit of 1.5 mg/kg, the estimated probability of mischaracterising a wheat lot containing 2 mg/kg DON as less than this concentration was reduced to 1%. DA - 2019/// PY - 2019/// DO - 10.3920/WMJ2019.2450 VL - 12 IS - 4 SP - 319-332 SN - 1875-0796 KW - heterogeneity KW - variance KW - sampling KW - grains KW - operating characteristic curve ER - TY - JOUR TI - Weed species differentiation using spectral reflectance and image classification AU - Sanders, J. T. AU - Everman, W. J. AU - Austin, R. AU - Roberson, G. T. AU - Richardson, R. J. T2 - ADVANCED ENVIRONMENTAL, CHEMICAL, AND BIOLOGICAL SENSING TECHNOLOGIES XV AB - Advancements in efficient unmanned aerial platforms and affordable sensors has led to renewed interest in remote sensing by agricultural producers and land managers for use as an efficient and convenient method of evaluating crop status and pest issues in their fields. For remote sensing to be employed as a viable and widespread tool for weed management, the accurate detection of distinct weed species must be possible through the use of analytical procedures on the resultant imagery. Additionally, the remote sensing platform and subsequent analysis must be capable of identifying these species across a wide range of heights. In 2017, a field study was performed to identify any weed height thresholds on the accurate detection and subsequent classification of three common broadleaf weed species in the southeastern United States: Palmer amaranth (Amaranthus palmeri), common ragweed (Ambrosia artemisiifolia) and sicklepod Senna obtusifolia) as well as the classification accuracy of image classifications performed on the species scale. Pots of the three species at heights of 5, 10, 15, and 30 cm were randomly arranged in a grid and 5-band multispectral imagery was collected at 15 m. Image analysis was used to identify the spectral reflectance behavior of the weed species and height combinations and to evaluate the accuracy of species based supervised classifications involving the three species. Supervised classification was able to discriminate between the three weed species with between 24-100% accuracy depending on height and species. Palmer amaranth classification accuracy was consistently 100%. Increased height of sicklepod and common ragweed plants did not reliably confer improved accuracy but the species were correctly identified with at least 24% and 60% accuracy, respectively. DA - 2019/// PY - 2019/// DO - 10.1117/12.2519306 VL - 11007 SP - SN - 1996-756X KW - Image analysis KW - multispectral KW - remote sensing KW - species discrimination KW - unmanned aerial vehicle KW - UAV KW - weed detection ER - TY - JOUR TI - Windbreak Wall-Vegetative Strip System to Reduce Air Emissions from Mechanically Ventilated Livestock Barns: Part 2—Swine House Evaluation AU - Ajami, Ali AU - Shah, Sanjay B. AU - Wang-Li, Lingjuan AU - Kolar, Praveen AU - Castillo, Miguel S. T2 - Water, Air, & Soil Pollution DA - 2019/12// PY - 2019/12// DO - 10.1007/s11270-019-4335-2 VL - 230 IS - 12 J2 - Water Air Soil Pollut LA - en OP - SN - 0049-6979 1573-2932 UR - http://dx.doi.org/10.1007/s11270-019-4335-2 DB - Crossref KW - TSP KW - Odor KW - Ammonia KW - Hydrogen sulfide KW - Porous windbreak wall KW - Switchgrass ER - TY - JOUR TI - Spatial and temporal variations of PM2.5 mass closure and inorganic PM2.5 in the Southeastern U.S. AU - Cheng, Bin AU - Wang-Li, Lingjuan AU - Meskhidze, Nicholas AU - Classen, John AU - Bloomfield, Peter T2 - Environmental Science and Pollution Research DA - 2019/9/13/ PY - 2019/9/13/ DO - 10.1007/s11356-019-06437-8 VL - 26 IS - 32 SP - 33181-33191 J2 - Environ Sci Pollut Res LA - en OP - SN - 0944-1344 1614-7499 UR - http://dx.doi.org/10.1007/s11356-019-06437-8 DB - Crossref KW - Chemical compositions KW - Gas-particle partitioning KW - Inorganic aerosols KW - Mass closure KW - PM2.5 KW - Spatiotemporal variations ER - TY - JOUR TI - Responses of secondary inorganic PM2.5 to precursor gases in an Ammonia Abundant area in North Carolina AU - Cheng, B. AU - Wang-Li, L. T2 - Aerosol and Air Quality Research AB - Secondary inorganic fine particulate matter (iPM2.5) constitutes a significant amount of the atmospheric PM2.5. The formation of secondary iPM2.5 is characterized by thermodynamic equilibrium gas-particle partitioning of gaseous ammonia (NH3) and aerosol ammonium (NH4+). To develop effective strategies for controlling atmospheric PM2.5, it is essential to understand the responses of secondary iPM2.5 to different precursor gases. In southeastern North Carolina, the amount of NH3 is in excess to fully neutralize acidic gases (i.e., NH3-rich conditions). NH3-rich conditions are mainly attributed to the significant NH3 emissions in the region, especially from the large amounts of animal feeding operation (AFO). To gain a better understanding of the impact of NH3 on the formation of secondary iPM2.5 in this area, the responses of iPM2.5 to precursor gases under different ambient conditions were investigated based upon three-year monitoring data of the chemical components in iPM2.5, gaseous pollutants, and meteorological conditions. The gas ratio (GR) was used to assess the degree of neutralization via NH3, and ISORROPIA II model simulation was used to examine the responses of iPM2.5 to changes in the total NH3, the total sulfuric acid (H2SO4), and the total nitric acid (HNO3). It was discovered that under different ambient temperature and humidity conditions, the responses of iPM2.5 to precursor gases vary. In general, iPM2.5 responds nonlinearly to the total NH3 but linearly to the total H2SO4 and the total HNO3. In NH3-rich regions, iPM2.5 is not sensitive to changes in the total NH3, but it is very sensitive to changes in the total H2SO4 and/or the total HNO3. Reducing the total H2SO4, as opposed to the total HNO3 or the total NH3, leads to a significant reduction in iPM2.5 and is thus a more effective strategy for decreasing the concentration of iPM2.5. This research provides insight into controlling and regulating PM2.5 in NH3-rich regions. DA - 2019/// PY - 2019/// DO - 10.4209/aaqr.2018.10.0384 VL - 19 IS - 5 SP - 1126-1138 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85069175937&partnerID=MN8TOARS KW - Ammonia KW - Inorganic PM2.5 KW - Thermodynamic equilibrium modeling KW - ISORROPIA II KW - Animal feeding operations ER - TY - JOUR TI - Windbreak Wall-Vegetative Strip System to Reduce Air Emissions from Mechanically Ventilated Livestock Barns—Part 3: Layer House Evaluation AU - Ajami, Ali AU - Shah, Sanjay B. AU - Wang-Li, Lingjuan AU - Kolar, Praveen AU - Castillo, Miguel S. T2 - Water, Air, & Soil Pollution DA - 2019/12// PY - 2019/12// DO - 10.1007/s11270-019-4345-0 VL - 230 IS - 12 J2 - Water Air Soil Pollut LA - en OP - SN - 0049-6979 1573-2932 UR - http://dx.doi.org/10.1007/s11270-019-4345-0 DB - Crossref KW - TSP KW - Odor KW - Ammonia KW - Hydrogen sulfide KW - Porous windbreak wall KW - Switchgrass ER - TY - JOUR TI - Role of resource allocation and transport in emergence of cross-feeding in microbial consortia AU - Schepens, Diana AU - Carlson, Ross P. AU - Heys, Jeff AU - Beck, Ashley E. AU - Gedeon, Tomáš T2 - Journal of Theoretical Biology AB - Microbial communities that implement mutual cross-feeding are commonly observed in nature and with synthetic constructs in laboratory experiments. A mathematical model of competition in a chemostat is developed to investigate the role that resource allocation and transport of metabolites play in cooperation. The model contains four cell types that differ by whether they produce two, one, or none of two essential metabolites. Producing cell types may export these resources into the environment, and those that do not produce both metabolites must import the missing resource. The contribution to the emergence of a collaborative consortium of single resource producers from the transport rate of these metabolites and the type of transport used by the cell (active vs. passive) is studied. Multiple instances of bi-stability and tri-stability are observed, and the effect of the initial concentration of a non-cooperative cheater cell type on the final outcome of the competition is examined. When the cost of producing metabolites is introduced into the model, significant changes to the outcome of the competition are observed, including coexistence of multiple cell types. DA - 2019/4// PY - 2019/4// DO - 10.1016/j.jtbi.2019.01.030 VL - 467 SP - 150-163 KW - Chemostat model KW - Cooperation KW - Metabolite production ER - TY - JOUR TI - Adolescent life values: An exploratory study of differences and similarities by urbanicity AU - Schmitt-Wilson, Sarah AU - Vaterlaus, J. Mitchell AU - Beck, Ashley T2 - The Social Science Journal AB - This exploratory correlational study examined whether life values (i.e., goals or principles that guide peoples’ lives) differed by urbanicity. The nationally representative sample included adolescents (N = 13,130) from urban, suburban, and rural communities in the USA. Contrary to our hypotheses, there were few differences in life values among urban, suburban, and rural adolescents in economic, educational, occupational, family, and relationship values. Most differences between urban and rural were observed in social values. This study provides insights into the role of urbanicity in adolescents' life values. DA - 2019/2// PY - 2019/2// DO - 10.1016/j.soscij.2019.02.001 VL - 2 KW - Life values KW - Adolescents KW - Rural KW - Urban ER - TY - JOUR TI - Integration in a depot-based decentralized biorefinery system: Corn stover-based cellulosic biofuel AU - Kim, Seungdo AU - Dale, Bruce E AU - Jin, Mingjie AU - Thelen, Kurt D AU - Zhang, Xuesong AU - Meier, Paul AU - Reddy, Ashwan Daram AU - Jones, Curtis Dinneen AU - Cesar Izaurralde, Roberto AU - Balan, Venkatesh AU - others T2 - GCB Bioenergy DA - 2019/// PY - 2019/// ER - TY - JOUR TI - Consequential Life Cycle Assessment of Swine Manure Management within a Thermal Gasification Scenario AU - Sharara, Mahmoud AU - Kim, Daesoo AU - Sadaka, Sammy AU - Thoma, Greg T2 - ENERGIES AB - Sustainable swine manure management is critical to reducing adverse environmental impacts on surrounding ecosystems, particularly in regions of intensive production. Conventional swine manure management practices contribute to agricultural greenhouse gas (GHG) emissions and aquatic eutrophication. There is a lack of full-scale research of the thermochemical conversion of solid-separated swine manure. This study utilizes a consequential life cycle assessment (CLCA) to investigate the environmental impacts of the thermal gasification of swine manure solids as a manure management strategy. CLCA is a modeling tool for a comprehensive estimation of the environmental impacts attributable to a production system. The present study evaluates merely the gasification scenario as it includes manure drying, syngas production, and biochar field application. The assessment revealed that liquid storage of manure had the highest contribution of 57.5% to GHG emissions for the entire proposed manure management scenario. Solid-liquid separation decreased GHG emissions from the manure liquid fraction. Swine manure solids separation, drying, and gasification resulted in a net energy expenditure of 12.3 MJ for each functional unit (treatment of 1 metric ton of manure slurry). Land application of manure slurry mixed with biochar residue could potentially be credited with 5.9 kg CO2-eq in avoided GHG emissions, and 135 MJ of avoided fossil fuel energy. Manure drying had the highest share of fossil fuel energy use. Increasing thermochemical conversion efficiency was shown to decrease overall energy use significantly. Improvements in drying technology efficiency, or the use of solar or waste-heat streams as energy sources, can significantly improve the potential environmental impacts of manure solids gasification. DA - 2019/11// PY - 2019/11// DO - 10.3390/en12214081 VL - 12 IS - 21 SP - SN - 1996-1073 KW - life cycle assessment KW - environmental impact KW - greenhouse gas KW - gasification KW - swine manure management ER - TY - JOUR TI - Anaerobic digestion, solid-liquid separation, and drying of dairy manure: Measuring constituents and modeling emission AU - Aguirre-Villegas, Horacio A. AU - Larson, Rebecca A. AU - Sharara, Mahmoud A. T2 - SCIENCE OF THE TOTAL ENVIRONMENT AB - Anaerobic digestion (AD) and solid-liquid separation (SLS) can increase operational flexibility at livestock facilities, but they can also affect environmental impacts during downstream manure handling. In this study, manure was characterized before and after AD, SLS, and drying. The measured data were used as inputs to models to estimate greenhouse gas (GHG) and ammonia (NH3) emissions during manure storage and land application. Nine dairy farms were sampled between each processing component to evaluate total solids (TS), volatile solids (VS), chemical oxygen demand (COD), total nitrogen (TN), total ammoniacal nitrogen (TAN), total phosphorus (TP), and total potassium (TK). AD systems with co-digestion have higher VS reduction than AD systems processing only dairy manure. SLS data indicate that both screw presses and centrifuges achieve higher separation efficiencies (mass in the solids) for TS and VS than for the other manure constituents. The farm with centrifugation achieves the highest separation efficiency for TP. TAN and TK are not well concentrated in the solids fraction for any processing system. TAN remains entirely within the liquid fraction, showing that each constituent has its own separation profile. Drying manure results in moisture, VS, and TAN losses. Since TAN stays with the liquids, these losses are negligible. When analyzing modeling results, most GHGs are emitted during storage as methane. However, land application is the major emitter of nitrous oxide and NH3. Both AD and SLS can reduce GHG emissions, with the combined AD and SLS scenario achieving the highest reduction (41%). AD increases NH3 emissions during storage due to the mineralization process during digestion. SLS alone can achieve significant GHG emission reductions (38%) even greater than AD when using actual performance data from operating systems. Both AD and SLS have the potential to reach higher GHG and NH3 emission reductions with improved technology efficiencies and management. DA - 2019/12/15/ PY - 2019/12/15/ DO - 10.1016/j.scitotenv.2019.134059 VL - 696 SP - SN - 1879-1026 KW - Anaerobic digestion KW - Solid-liquid separation KW - Separation efficiency KW - Dairy manure KW - GHG emissions KW - Ammonia emissions ER - TY - JOUR TI - Survey of Practices by Growers in the Virginia-Carolina Region Regarding Digging and Harvesting Peanut AU - Jordan, David L. AU - Hare, Andrew T. AU - Roberson, Gary T. AU - Ward, Jason AU - Shew, Barbara B. AU - Brandenburg, Rick L. AU - Anco, Dan AU - Thomas, James AU - Balota, Maria AU - Mehl, Hillary AU - Taylor, Sally T2 - CROP FORAGE & TURFGRASS MANAGEMENT AB - Core Ideas Harvesting peanut requires approximately twice as much time to complete as the time required for digging peanut. Fifty-six percent of growers predicted when optimum yield would occur based on the sample provided within the recommended timeframe. Reported yield was positively correlated with the use of prohexadione calcium. DA - 2019/11/27/ PY - 2019/11/27/ DO - 10.2134/cftm2019.07.0057 VL - 5 IS - 1 SP - SN - 2374-3832 ER - TY - JOUR TI - Multipoint High-Frequency Sampling System to Gain Deeper Insights on the Fate of Nitrate in Artificially Drained Fields AU - Liu, Wenlong AU - Maxwell, Bryan AU - Birgand, François AU - Youssef, Mohamed AU - Chescheir, George AU - Tian, Shiying T2 - Journal of Irrigation and Drainage Engineering AB - The application of high-frequency measurements could potentially enhance current understanding of the hydrology and biogeochemistry of artificially drained agricultural lands. In addition to intensive drainage flow measurements (every 15 min), two high-frequency sampling systems were implanted to monitor, on an hourly basis, nitrate-nitrogen concentrations [NO3-N] in the drainage outlet and at multiple points in the shallow groundwater. This paper provides a description of this novel in situ measurement system and reports example data obtained during a rainfall event. High-frequency measurements of [NO3-N] at the field edge could potentially advance understanding of agricultural drainage systems, including increased accuracy of (1) nitrate loading estimates, (2) spatiotemporal dynamics of nitrate export during rainfall events, and (3) nonlinear hydrochemical (C-Q) relationship. Combining high-frequency measurements of [NO3-N] in drainage water at the field edge and shallow groundwater within the field gives the opportunity for the next steps in identifying and quantifying key processes, mechanisms, hot moments, and active zones that control nitrate dynamics in drained agricultural land. DA - 2019/1// PY - 2019/1// DO - 10.1061/(ASCE)IR.1943-4774.0001438 VL - 146 IS - 1 SP - 06019012 J2 - J. Irrig. Drain Eng. LA - en OP - SN - 0733-9437 1943-4774 UR - http://dx.doi.org/10.1061/(ASCE)IR.1943-4774.0001438 DB - Crossref ER - TY - JOUR TI - Identification of QTL for Target Leaf Spot resistance in Sorghum bicolor and investigation of relationships between disease resistance and variation in the MAMP response AU - Kimball, Jennifer AU - Cui, Yaya AU - Chen, Dongqin AU - Brown, Pat AU - Rooney, William L. AU - Stacey, Gary AU - Balint-Kurti, Peter J. T2 - Scientific Reports AB - Target leaf spot (TLS) of sorghum, a foliar disease caused by the necrotrophic fungus Bipolaris cookei (also known as Bipolaris sorghicola), can affect grain yield in sorghum by causing premature drying of leaves and defoliation. Two sorghum recombinant inbred line (RIL) populations, BTx623/BTx642 and BTx623/SC155-14E, were assessed for TLS resistance in replicated trials. Using least square mean trait data, four TLS resistance QTL were identified, two in each population. Of these, three were previously unidentified while a major QTL on chromosome 5 in the BTx623/BTx642 RIL population corresponded to the previously identified TLS resistance gene ds1. A set of sorghum lines were assessed for production of reactive oxygen species induced by treatment with the microbe-associated molecular pattern (MAMP) flg22 (a derivative of flagellin). Flg22-induced ROS production varied between lines in a consistent fashion. One QTL associated with variation in the flg22 response was detected in the RIL populations. No evidence was found to link variation in the MAMP response to variation in TLS resistance. DA - 2019/12/4/ PY - 2019/12/4/ DO - 10.1038/s41598-019-54802-x VL - 9 IS - 1 J2 - Sci Rep LA - en OP - SN - 2045-2322 UR - http://dx.doi.org/10.1038/s41598-019-54802-x DB - Crossref ER - TY - JOUR TI - Retrofitting a grass swale with rock check dams: hydrologic impacts AU - Winston, Ryan J. AU - Powell, Jacob T. AU - Hunt, William F. T2 - URBAN WATER JOURNAL AB - The hydrologic performance of a grass swale, a common stormwater control measure often utilized to drain roads, may potentially be improved using simple retrofits. Two rock check dams were retrofitted into an existing grass swale located in Knightdale, North Carolina, USA. The swale was monitored before and after check dam installation, and the addition of check dams improved runoff volume reduction (17%), peak flow mitigation, and hydraulic retention time in the swale, particularly for small (< 19 mm) and moderate (19–38 mm) rainfall events. The check dams were effective filters of gross solids, which eventually led to clogging and caused extended inundation and subsequent loss of swale vegetation. Because check dams are relatively inexpensive and simple vis-à-vis other stormwater control measure enhancements, their use for stormwater treatment is encouraged, provided they are adequately maintained. DA - 2019/7/3/ PY - 2019/7/3/ DO - 10.1080/1573062X.2018.1455881 VL - 16 IS - 6 SP - 404-411 SN - 1744-9006 KW - Clogging KW - highway runoff KW - peak flow rate KW - low impact development KW - runoff reduction KW - vegetated swale ER - TY - JOUR TI - Listeria monocytogenes at the human-wildlife interface: black bears (Ursus americanus) as potential vehicles for Listeria AU - Parsons, Cameron AU - Niedermeyer, Jeff AU - Gould, Nicholas AU - Brown, Phillip AU - Strules, Jennifer AU - Parsons, Arielle W. AU - Mesa-Cruz, J. Bernardo AU - Kelly, Marcella J. AU - Hooker, Michael J. AU - Chamberlain, Michael J. AU - Olfenbuttel, Colleen AU - DePerno, Christopher AU - Kathariou, Sophia T2 - MICROBIAL BIOTECHNOLOGY AB - Summary Listeria monocytogenes is the causative agent of the foodborne illness listeriosis, which can result in severe symptoms and death in susceptible humans and other animals. L. monocytogenes is ubiquitous in the environment and isolates from food and food processing, and clinical sources have been extensively characterized. However, limited information is available on L. monocytogenes from wildlife, especially from urban or suburban settings. As urban and suburban areas are expanding worldwide, humans are increasingly encroaching into wildlife habitats, enhancing the frequency of human–wildlife contacts and associated pathogen transfer events. We investigated the prevalence and characteristics of L. monocytogenes in 231 wild black bear capture events between 2014 and 2017 in urban and suburban sites in North Carolina, Georgia, Virginia and United States, with samples derived from 183 different bears. Of the 231 captures, 105 (45%) yielded L. monocytogenes either alone or together with other Listeria . Analysis of 501 samples, primarily faeces, rectal and nasal swabs for Listeria spp . , yielded 777 isolates, of which 537 (70%) were L. monocytogenes. Most L. monocytogenes isolates exhibited serotypes commonly associated with human disease: serotype 1/2a or 3a (57%), followed by the serotype 4b complex (33%). Interestingly, approximately 50% of the serotype 4b isolates had the IVb‐v1 profile, associated with emerging clones of L. monocytogenes. Thus, black bears may serve as novel vehicles for L. monocytogenes , including potentially emerging clones. Our results have significant public health implications as they suggest that the ursine host may preferentially select for L. monocytogenes of clinically relevant lineages over the diverse listerial populations in the environment. These findings also help to elucidate the ecology of L . monocytogenes and highlight the public health significance of the human–wildlife interface. DA - 2019/// PY - 2019/// DO - 10.1111/1751-7915.13509 ER - TY - JOUR TI - Influence of wire configuration on resistance to fragment distraction of tension bands placed in a greater trochanteric osteotomy model AU - Thompson, Elizabeth AU - Robe, Amir K. AU - Roe, Simon C. AU - Cole, Jacqueline H. T2 - VETERINARY SURGERY AB - Abstract Objective To determine the influence of wiring configurations on initial tension and resistance to tensile loads in tension band constructs without the contributions of Kirschner‐wire stabilization. Study design Experimental study. Sample population A solid brass femur model manufactured on the basis of computed tomography of a normal right femur of a 30‐kg dog modified by transection of the greater trochanter and placement of two pins that did not cross the simulated osteotomy. Methods Four tension band configurations were applied to the metal trochanteric osteotomy model: figure‐of‐eight with one twist (OT), figure‐of‐eight with two twists (TT), dual interlocking single loop, and double loop (DL). Configurations were tested under both monotonic loading (n = 8 per configuration) and incremental cyclic loading (n = 8 per configuration). Initial tension after tying, residual tension remaining after each cycle, and failure load at 2 mm of displacement (considered equivalent to clinical failure) were compared between configurations. Results The initial tension and the load to 2 mm of displacement were lower for OT wires compared with TT wires. The DL was the strongest and most stable configuration, generating 2.3 to 3.5 times greater initial tension, maintaining a greater percentage of residual tension under incremental cyclic loads, and resisting 2.0 to 2.4 times greater load before failure at 2 mm. Failure load was highly correlated with initial tension. Conclusion Wire configurations reaching greater initial tension, such as the DL, allowed constructs to resist higher tensile loads. Clinical impact Wire configurations allowing higher initial tension may be warranted when tension bands are expected to sustain high tensile loads. DA - 2019/// PY - 2019/// DO - 10.1111/vsu.13350 ER - TY - JOUR TI - Baseline characterization data for raw rice husk AU - Kolar, Praveen AU - Jin, Han T2 - DATA IN BRIEF AB - There is a significant interest in using agricultural wastes such as rice husk as a precursor for the synthesis of adsorbents and catalysts. In this article, readers will find valuable baseline characterization data related to physical and chemical properties of raw rice husk including BET specific surface area, acid value, the point of zero charge, elemental analysis, Time-of-Flight Secondary Ion Mass Spectrometric Analysis X-Ray Photoelectron Spectroscopic Analysis, and Scanning Electron Microscope-Energy Dispersive Spectroscopic Analysis. It is expected that the baseline raw data presented in this article will be useful for researchers around the world who are working on chemically modifying rice husk for valorizing them for applications in adsorption, catalysis, and energy storage. DA - 2019/8// PY - 2019/8// DO - 10.1016/j.dib.2019.104219 VL - 25 SP - SN - 2352-3409 KW - Rice husk KW - Characterization KW - Acid value KW - PZC KW - XPS KW - SEM-EDX KW - Specific surface area ER - TY - JOUR TI - Physicochemical data of p-cresol, butyric acid, and ammonia AU - Kolar, Praveen AU - Classen, John AU - Hall, Steven G. T2 - Data in Brief AB - There is a renewed interest in treating odorous contaminants such as butyric acid, p-cresol, and ammonia that are emitted from animal farming operations. However, developing newer treatment technologies require quantitative information regarding the properties of the target pollutants. Therefore, in this communication, baseline data related to physicochemical and thermodynamic properties of butyric acid, p-cresol, and ammonia were predicted using computational chemistry. Density functional theory was employed via B3LYP functional coupled with polarized 6-31G (d) basis set without any solvent effects using Gaussian 16W and GaussView6. The predicted baseline properties collected here are expected to be useful to scientists and engineers working in environmental mitigation technologies in developing treatment processes and make the animal agricultural industry environmental friendly and sustainable. DA - 2019/10// PY - 2019/10// DO - 10.1016/j.dib.2019.104356 VL - 26 SP - 104356 J2 - Data in Brief LA - en OP - SN - 2352-3409 UR - http://dx.doi.org/10.1016/j.dib.2019.104356 DB - Crossref KW - Butyric acid KW - p-cresol KW - Ammonia KW - Indole KW - Density functional theory ER - TY - JOUR TI - Effect of Enzyme Interaction with Lignin Isolated from Pretreated Miscanthus x giganteus on Cellulolytic Efficiency AU - Jung, Woochul AU - Sharma-Shivappa, Ratna AU - Kolar, Praveen T2 - PROCESSES AB - The effect of binding between the lignin isolates from an alkali (NaOH)– and an acid (H2SO4)– pretreated Miscanthus and cellulolytic enzymes in Cellic® CTec2 was investigated. Additonally, cellobiose and Avicel were enzymatically hydrolyzed with and without lignin isolates to study how enzyme binding onto lignin affects its conversion to glucose. Three carbohydrate–lignin loadings (0.5:0.25, 0.5:0.5, and 0.5:1.0% (w/v)) were employed. The results indicated that β-glucosidase (BG) had a strong tendency to bind to all lignin isolates. The overall tendency of enzyme binding onto lignin isolate was similar regardless of pretreatment chemical concentration. Though enzyme binding onto lignin isolates was observed, hydrolysis in the presence of these isolates did not have a significant (p > 0.05) impact on glucose production from cellobiose and Avicel. Cellobiose to glucose conversion of 99% was achieved via hydrolysis at both 5 and 10 FPU/g carbohydrate. Hydrolysis of Avicel with 5 and 10 FPU/g CTec2 resulted in 29.3 and 47.7% conversion to glucose, respectively. DA - 2019/10// PY - 2019/10// DO - 10.3390/pr7100755 VL - 7 IS - 10 SP - SN - 2227-9717 KW - miscanthus KW - hydrolysis KW - lignin KW - inhibition KW - pretreatment ER - TY - JOUR TI - Quantifying MAMP-induced Production of Reactive Oxygen Species in Sorghum and Maize AU - Samira, Rozalynne AU - Zhang, Xinye AU - Kimball, Jennifer AU - Cui, Yaya AU - Stacey, Gary AU - Balint-Kurti, Peter T2 - BIO-PROTOCOL DA - 2019/// PY - 2019/// DO - 10.21769/bioprotoc.3304 VL - 9 IS - 14 J2 - BIO-PROTOCOL LA - en OP - SN - 2331-8325 UR - http://dx.doi.org/10.21769/BioProtoc.3304 DB - Crossref ER - TY - JOUR TI - Analysis of leaf microbiome composition of near‐isogenic maize lines differing in broad‐spectrum disease resistance AU - Wagner, Maggie R. AU - Busby, Posy E. AU - Balint‐Kurti, Peter T2 - New Phytologist AB - Summary Plant genotype strongly affects disease resistance, and also influences the composition of the leaf microbiome. However, these processes have not been studied and linked in the microevolutionary context of breeding for improved disease resistance. We hypothesised that broad‐spectrum disease resistance alleles also affect colonisation by nonpathogenic symbionts. Quantitative trait loci (QTL) conferring resistance to multiple fungal pathogens were introgressed into a disease‐susceptible maize inbred line. Bacterial and fungal leaf microbiomes of the resulting near‐isogenic lines were compared with the microbiome of the disease‐susceptible parent line at two time points in multiple fields. Introgression of QTL from disease‐resistant lines strongly shifted the relative abundance of diverse fungal and bacterial taxa in both 3‐wk‐old and 7‐wk‐old plants. Nevertheless, the effects on overall community structure and diversity were minor and varied among fields and years. Contrary to our expectations, host genotype effects were not any stronger in fields with high disease pressure than in uninfected fields, and microbiome succession over time was similar in heavily infected and uninfected plants. These results show that introgressed QTL can greatly improve broad‐spectrum disease resistance while having only limited and inconsistent pleiotropic effects on the leaf microbiome in maize. DA - 2019/11/26/ PY - 2019/11/26/ DO - 10.1111/nph.16284 VL - 225 IS - 5 SP - 2152-2165 J2 - New Phytol LA - en OP - SN - 0028-646X 1469-8137 UR - http://dx.doi.org/10.1111/nph.16284 DB - Crossref KW - breeding KW - disease ecology KW - disease resistance KW - introgression KW - maize KW - microbiome KW - pathology KW - phyllosphere ER - TY - JOUR TI - Insights from using in-situ ultraviolet–visible spectroscopy to assess nitrogen treatment and subsurface dynamics in a regenerative stormwater conveyance (RSC) system AU - Cizek, Adrienne R. AU - Johnson, Jeffrey P. AU - Birgand, François AU - Hunt, William F. AU - McLaughlin, Richard A. T2 - Journal of Environmental Management AB - Regenerative stormwater conveyance (RSC) is a recently developed stormwater control measure that marries the concepts of bioretention and stream restoration. RSC mitigates stormwater runoff by converting surface flow to subsurface seepage using a series of pools and riffles built over a sand media bed. Subsurface seepage flows through media and exits the RSC beneath the outlet weir. Previous studies on RSC pollutant mitigation have focused on surface flow discharges from the RSC. To date, no known research has been conducted on the potential pollutant contributions of RSC seepage, despite the fact that this water also enters receiving waters. This research used Multi-Point Sampling coupled with in-situ ultraviolet–visual spectroscopy to measure nitrogen in seepage during simulated storm events (n = 9) at a field-scale RSC in Raleigh, North Carolina. Calibrations between light absorbance and concentrations were acceptable (Nash-Sutcliffe coefficient > 0.65) for nitrate and total ammoniacal nitrogen (TAN) and very good (Nash-Sutcliffe coefficient > 0.90) for total Kjehdahl nitrogen (TKN). Early storm simulations revealed some initial nutrient flushing from the substrate, which subsided by the third simulation. Overall, subsurface seepage nitrate, TAN, and TKN concentrations were lower by 29%, 57%, and 4% relative to storm inflow concentrations, respectively. Computed subsurface nitrogen concentrations demonstrated temporal variability, highlighting dynamic transport and biogeochemical transformations in saturated and unsaturated conditions. Nitrogen concentrations were lower in seepage than in surface flow; however, due to the high volume of runoff converted to seepage, nitrogen loads discharged in seepage can be larger than those of surface flow. Further research is needed to examine subsurface pollutant reductions under varying hydrologic and seasonal conditions. DA - 2019/12// PY - 2019/12// DO - 10.1016/j.jenvman.2019.109656 VL - 252 SP - 109656 J2 - Journal of Environmental Management LA - en OP - SN - 0301-4797 UR - http://dx.doi.org/10.1016/j.jenvman.2019.109656 DB - Crossref KW - Regenerative stormwater conveyance KW - Ultraviolet-visual spectroscopy KW - UV spectroscopy KW - Stormwater KW - Seepage KW - Nitrogen ER - TY - JOUR TI - Vulnerability of resource users in Louisiana's oyster fishery to environmental hazards AU - Humphries, Austin T. AU - Josephs, Lauren I. AU - La Peyre, Megan K. AU - Hall, Steven AU - Beech, Rachel Dowty T2 - ECOLOGY AND SOCIETY AB - Humphries, A. T., L. I. Josephs, M. K. La Peyre, S. Hall, and R. Dowty Beech. 2019. Vulnerability of resource users in Louisiana’s oyster fishery to environmental hazards. Ecology and Society 24(3):37. https://doi.org/10.5751/ES-11101-240337 DA - 2019/9// PY - 2019/9// DO - 10.5751/ES-11101-240337 VL - 24 IS - 3 SP - SN - 1708-3087 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85073540039&partnerID=MN8TOARS KW - adaptation KW - Crassostrea virginica KW - fisheries KW - Gulf of Mexico KW - management KW - shellfish ER - TY - JOUR TI - Contrasting behavior of nitrate and phosphate flux from high flow events on small agricultural and urban watersheds AU - Frazar, Sarah AU - Gold, Arthur J. AU - Addy, Kelly AU - Moatar, Florentina AU - Birgand, François AU - Schroth, Andrew W. AU - Kellogg, D. Q. AU - Pradhanang, Soni M. T2 - Biogeochemistry DA - 2019/9/25/ PY - 2019/9/25/ DO - 10.1007/s10533-019-00596-z VL - 145 IS - 1-2 SP - 141-160 J2 - Biogeochemistry LA - en OP - SN - 0168-2563 1573-515X UR - http://dx.doi.org/10.1007/s10533-019-00596-z DB - Crossref KW - Agricultural KW - Nitrate KW - Nutrient flux KW - Phosphate KW - Sensor KW - Storm flow KW - Urban KW - Watershed ER - TY - JOUR TI - Dominant, Heritable Resistance to Stewart’s Wilt in Maize Is Associated with an Enhanced Vascular Defense Response to Infection with Pantoea stewartii AU - Doblas-Ibáñez, Paula AU - Deng, Kaiyue AU - Vasquez, Miguel F. AU - Giese, Laura AU - Cobine, Paul A. AU - Kolkman, Judith M. AU - King, Helen AU - Jamann, Tiffany M. AU - Balint-Kurti, Peter AU - De La Fuente, Leonardo AU - Nelson, Rebecca J. AU - Mackey, David AU - Smith, Laurie G. T2 - Molecular Plant-Microbe Interactions® AB - Vascular wilt bacteria such as Pantoea stewartii, the causal agent of Stewart’s bacterial wilt of maize (SW), are destructive pathogens that are difficult to control. These bacteria colonize the xylem, where they form biofilms that block sap flow leading to characteristic wilting symptoms. Heritable forms of SW resistance exist and are used in maize breeding programs but the underlying genes and mechanisms are mostly unknown. Here, we show that seedlings of maize inbred lines with pan1 mutations are highly resistant to SW. However, current evidence suggests that other genes introgressed along with pan1 are responsible for resistance. Genomic analyses of pan1 lines were used to identify candidate resistance genes. In-depth comparison of P. stewartii interaction with susceptible and resistant maize lines revealed an enhanced vascular defense response in pan1 lines characterized by accumulation of electron-dense materials in xylem conduits visible by electron microscopy. We propose that this vascular defense response restricts P. stewartii spread through the vasculature, reducing both systemic bacterial colonization of the xylem network and consequent wilting. Though apparently unrelated to the resistance phenotype of pan1 lines, we also demonstrate that the effector WtsE is essential for P. stewartii xylem dissemination, show evidence for a nutritional immunity response to P. stewartii that alters xylem sap composition, and present the first analysis of maize transcriptional responses to P. stewartii infection. DA - 2019/12// PY - 2019/12// DO - 10.1094/MPMI-05-19-0129-R VL - 32 IS - 12 SP - 1581-1597 J2 - MPMI LA - en OP - SN - 0894-0282 1943-7706 UR - http://dx.doi.org/10.1094/MPMI-05-19-0129-R DB - Crossref KW - bacterial pathogenesis KW - electron-dense materials KW - maize KW - Pantoea stewartii KW - plant responses to pathogens KW - secretion and cell wall changes KW - Stewart's bacterial wilt KW - type-3 secretion KW - vascular defense response KW - WtsE KW - xylem-dwelling bacteria ER - TY - JOUR TI - Estimation of evapotranspiration and its parameters for pine, switchgrass, and intercropping with remotely-sensed images based geospatial modeling AU - Panda, Sudhanshu Sekhar AU - Amatya, Devendra Man AU - Muwamba, Augustine AU - Chescheir, George T2 - ENVIRONMENTAL MODELLING & SOFTWARE AB - Intercropping switchgrass (Panicum virgatum) with pine can increase bioenergy feedstock production without land opportunity costs but can potentially alter water budgets. Measuring evapotranspiration (ET) and its parameters (stomatal conductance (gs), leaf area index (LAI), canopy temperature (Tc), and soil moisture (SM)) across cropping systems is costly and time-consuming. However, interpretation of remotely-sensed data can facilitate the effective assessment of relative ET demands among competing forest landuses. This study develops and tests geospatial models informed by a normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI), vegetation vigor index (VVI), and other spectral information to estimate ET and its parameters, which are measured on experimental watersheds with young pines and natural understory (YP), switchgrass only (SG), and young pine intercropped with switchgrass (IC). The treatment watersheds were replicated on three sites located across the Southeastern U.S. in Carteret, NC; Calhoun, MS; and Greene, AL. Despite the growth inconsistency for the SG only treatment, remote modeling estimation of ET parameters yielded an acceptable R2 > 0.70, and the ET model yielded R2 of 0.50 and a standard error of prediction of 0.94. However, ET and ET parameter model estimation for the IC performed somewhat less satisfactorily, with an R2 of 0.47, 0.59, 0.56, 0.81, and 0.57 for ET, LAI, gs, Tc, and SM, respectively, potentially due to inconsistencies in Landsat image pixel size and landuse homogeneity. Moreover, ET parameter models for the YP site performed rather poorly, with R2 = 0.28, 0.63, and 0.76 for LAI, gs, and Tc, respectively. Additionally, image analysis automation was created with Python scripting and geospatial models. The findings from this study suggest that inclusion of more spatial variability, sound data mining, ultra-high resolution imagery and advanced image processing approaches to account for potential modeling uncertainties can enhance the predictive capability of models to remotely estimate environmental parameters including ET. Radial Basis Function Network (RBFN) based models provided promising results for estimating ET and ET parameters using remotely-sensed digital information when they are prepared with advanced data mining, but it is likely that laypersons may find these models difficult to use. However, forest managers with access to neural network software can use our devised RBFN training models for estimating those forest hydrologic parameters with better accuracy. DA - 2019/11// PY - 2019/11// DO - 10.1016/j.envsoft.2019.07.012 VL - 121 SP - SN - 1873-6726 KW - ArcGIS ModelBuilder KW - Canopy temperature KW - Data mining KW - Evapotranspiration KW - Landsat KW - Orthoimagery KW - Python script KW - RBFN KW - Software development KW - Soil moisture KW - SPOT KW - Stomatal conductance KW - Visual basics studios ER - TY - JOUR TI - Valorization of Swine Manure into Hydrochars AU - Lentz, Zac AU - Kolar, Praveen AU - Classen, John J. T2 - Processes AB - There is a significant interest in valorizing swine manure that is produced in enormous quantities. Therefore, considering the high moisture content in swine manure, the objective of this research was to convert manure slurry into hydrochars via hydrothermal carbonization and analyze the yields, pH, energy contents, and thermal and oxidation kinetic parameters. Experiments were performed in triplicate in 250 mL kettle reactors lined with polypropylene at 180 °C, 200 °C, 240 °C, 220 °C, and 260 °C for 24 h. Analyses of the results indicated that the process temperature affected the hydrochar yields, with yield generally decreasing with increasing temperature, but it had little effect on the composition of the hydrochar. The hydrochars were found to have higher volatile contents and H/C and O/C ratios and about 85% of the energy compared to coal. However, the presence of high fraction (35–38%) of ash in hydrochars is a serious concern and needs to be addressed before the complete utilization of hydrochars as fuels. The surface characterization of hydrochars coupled with wet chemistry experiments indicated that hydrochars were equipped with nitrogen functional groups with points of zero charges between 6.76 and 7.85, making them suitable as adsorbents and soil remediation agents and energy storage devices. DA - 2019/8/23/ PY - 2019/8/23/ DO - 10.3390/pr7090560 VL - 7 IS - 9 SP - 560 J2 - Processes LA - en OP - SN - 2227-9717 UR - http://dx.doi.org/10.3390/pr7090560 DB - Crossref KW - swine manure KW - valorization KW - char KW - hydrothermal carbonization KW - characterization ER - TY - JOUR TI - Increased Duration of Drying–Rewetting Cycles Increases Nitrate Removal in Woodchip Bioreactors AU - Maxwell, Bryan M. AU - Birgand, François AU - Schipper, Louis A. AU - Christianson, Laura E. AU - Tian, Shiying AU - Helmers, Matthew J. AU - Williams, David J. AU - Chescheir, George M. AU - Youssef, Mohamed A. T2 - Agricultural & Environmental Letters AB - Core Ideas Nitrate removal in woodchips increased linearly with drying–rewetting duration. Nitrate removal increased up to 172% in the longest drying–rewetting duration. Nitrate removal rates increased proportionally with dissolved organic C leaching. A previously reported experiment showed weekly drying–rewetting (DRW) cycles increase nitrate removal rates in woodchip‐based denitrifying bioreactors. A follow‐up experiment determined the effect of duration of unsaturated conditions on nitrate removal after rewetting. Three different levels of DRW duration were tested in a 105‐d column experiment ( n = 2), with woodchips left unsaturated once a week for either 2 h, 8 h, or 24 h. Increasing duration of unsaturated conditions significantly increased nitrate removal rates. The longest DRW duration of 24 h resulted in the greatest increase in nitrate removal rates, relative to constantly saturated woodchips, with mean rate increases reaching 172% by the end of the experiment. Results suggest nitrate removal in denitrifying bioreactors is carbon limited, with labile carbon made available during aerobic periods of DRW cycles the most likely cause of observed rate increases. Both studies show DRW cycles dramatically increase the nitrate removal efficiency of denitrifying bioreactors. DA - 2019/// PY - 2019/// DO - 10.2134/ael2019.07.0028 VL - 4 IS - 1 SP - SN - 2471-9625 UR - http://dx.doi.org/10.2134/ael2019.07.0028 ER - TY - JOUR TI - Comparison of empirical and mechanistic equations for vegetative filter strip pesticide mitigation in long-term environmental exposure assessments AU - Muñoz-Carpena, Rafael AU - Ritter, Amy AU - Fox, Garey A. T2 - Water Research AB - Recent advances in mechanistic modeling of vegetated filter strips (VFS) have made it possible to incorporate VFS mitigation into environmental exposure assessments (EEAs). However, outside of fixed efficiency approaches, there are no widely adopted and standardized procedures for incorporating VFS quantitative mitigation into long-term, higher-tier EEAs. A source of hesitation involves the use of empirical equations for predicting pesticide trapping by the VFS. A recent study evaluated existing empirical equations and a mechanistic mass-balance approach using the most extensive field database available of VFS pesticide efficiency from single-event storms. That study concluded that an updated empirical equation (Sabbagh equation) and a mechanistic mass-balance approach performed reasonably well. The objective of this research was to study the effect of upscaling the VFS trapping equations from single events into long-term EEAs. The U.S. EPA Pesticide in Water Calculator (PWC) model linked with the Vegetative Filter Strip MODeling system (VFSMOD) long-term EEA modeling framework (30 yr) was updated to incorporate the alternative trapping equations and tested VFS mitigation results under contrasting agroecological settings with varying erosion/sediment transport conditions. Differences in both acute and chronic 90th percentile estimated environmental exposure concentrations (EECs) were relatively small when comparing predictions using the four pesticide trapping equations. A global sensitivity analysis (GSA) also indicated that selection of a specific trapping equation for predicting EECs was less important than other important input factors such as the VFS length and pesticide properties. However, in terms of the percent reductions in EECs, the choice of pesticide trapping equation was as important as the VFS length. This research builds upon the conclusion of previous single-event studies that the mechanistic mass-balance and refit Sabbagh empirical equation were both valid for EEAs. The mass balance approach represents a reasonable option for regulatory agencies that prefer mechanistic approaches. DA - 2019/11// PY - 2019/11// DO - 10.1016/j.watres.2019.114983 VL - 165 SP - 114983 J2 - Water Research LA - en OP - SN - 0043-1354 UR - http://dx.doi.org/10.1016/j.watres.2019.114983 DB - Crossref KW - Pesticide mitigation KW - Environmental exposure assessment KW - Environmental exposure concentrations KW - Pesticide transport KW - Vegetative filter strip ER - TY - JOUR TI - DendriPeps: Expanding Dendrimer Functionality by Hybridizing Poly(amidoamine) (PAMAM) Scaffolds with Peptide Segments AU - Smith, Ryan J. AU - Gorman, Christopher B. AU - Menegatti, Stefano T2 - MACROMOLECULAR RAPID COMMUNICATIONS AB - Abstract In this work, the first synthesis of poly(amidoamine) (PAMAM) dendrimers whose branches are hybridized with peptide segments (DendriPeps) is reported. The intercalation of amino acids within the branches of PAMAMs provides supplementary internal functionalities to the coronal groups. Four DendriPep prototypes are synthesized with lysine or glutamic acid as “guest” amino acids, displaying, respectively, a primary amine or a carboxyl group, on generation (G)2 and G3 PAMAMs as host scaffolds. The precise control over the number, type, and topological placement of functional groups expands the functional behavior of DendriPeps beyond current PAMAM dendrimers toward new frontiers or colloids, drug delivery vectors, and catalysis. DA - 2019/11// PY - 2019/11// DO - 10.1002/marc.201900325 VL - 40 IS - 22 SP - SN - 1521-3927 KW - internally functionalized dendrimers KW - orthogonal protection strategies KW - poly(amidoamine) KW - polymer-peptide chemistry ER - TY - JOUR TI - Increasing the Effectiveness and Adoption of Agricultural Phosphorus Management Strategies to Minimize Water Quality Impairment AU - Osmond, D. L. AU - Shober, A. L. AU - Sharpley, A. N. AU - Duncan, E. W. AU - Hoag, D. L. K. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Phosphorus (P) is essential for optimum agricultural production, but it also causes water quality degradation when lost through erosion (sediment-attached P), runoff (soluble reactive P; SRP), or leaching (sediment-attached P or SRP). Implementation of conservation practices (CP) affects P at the source (avoiding), during transport (controlling), or at the water resource edge (trapping). Trade-offs often occur with CP implementation. For instance, multiple researchers have shown that conservation tillage reduces total P by over 50%, while increasing SRP by upward of 40%. Conservation tillage may increase water quality degradation as SRP is more bioavailable than is particulate P. Conservation practices must be implemented as a system of practices to increase redundancy and to address all loss pathways, such as P management with conservation tillage and a riparian buffer. Further, planning and adoption must be at a watershed scale to ensure practices are placed in critical source areas, thereby providing the most treatment for the least price. Farmers must be involved in watershed planning, which should include financial backstopping and educational outreach. It is imperative that CPs be used more effectively to reduce and retard off-site P losses. New and innovative CPs are needed to improve control of P leaching, address legacy stores of soil test P, and mitigate increased P losses expected with climate change. Without immediate changes to CP implementation, P losses will increase due to climate change, with a concomitant degradation of water quality. These changes must be made at a watershed scale and in an intentional and transparent manner. DA - 2019/// PY - 2019/// DO - 10.2134/jeq2019.03.0114 VL - 48 IS - 5 SP - 1204-1217 SN - 1537-2537 ER - TY - JOUR TI - Validation and Characterization of Maize Multiple Disease Resistance QTL AU - Martins, Lais B AU - Rucker, Elizabeth AU - Thomason, Wade AU - Wisser, Randall J AU - Holland, James B AU - Balint-Kurti, Peter T2 - G3 Genes|Genomes|Genetics AB - Abstract Southern Leaf Blight, Northern Leaf Blight, and Gray Leaf Spot, caused by ascomycete fungi, are among the most important foliar diseases of maize worldwide. Previously, disease resistance quantitative trait loci (QTL) for all three diseases were identified in a connected set of chromosome segment substitution line (CSSL) populations designed for the identification of disease resistance QTL. Some QTL for different diseases co-localized, indicating the presence of multiple disease resistance (MDR) QTL. The goal of this study was to perform an independent test of several of the MDR QTL identified to confirm their existence and derive a more precise estimate of allele additive and dominance effects. Twelve F2:3 family populations were produced, in which selected QTL were segregating in an otherwise uniform genetic background. The populations were assessed for each of the three diseases in replicated trials and genotyped with markers previously associated with disease resistance. Pairwise phenotypic correlations across all the populations for resistance to the three diseases ranged from 0.2 to 0.3 and were all significant at the alpha level of 0.01. Of the 44 QTL tested, 16 were validated (identified at the same genomic location for the same disease or diseases) and several novel QTL/disease associations were found. Two MDR QTL were associated with resistance to all three diseases. This study identifies several potentially important MDR QTL and demonstrates the importance of independently evaluating QTL effects following their initial identification. DA - 2019/9/1/ PY - 2019/9/1/ DO - 10.1534/g3.119.400195 VL - 9 IS - 9 SP - 2905-2912 LA - en OP - SN - 2160-1836 UR - http://dx.doi.org/10.1534/g3.119.400195 DB - Crossref KW - Disease KW - Maize KW - QTL KW - Resistance KW - Genetics of Immunity ER - TY - JOUR TI - Optimum Nitrogen Rates for Maize and Wheat in North Carolina AU - Austin, Robert AU - Osmond, Deanna AU - Shelton, Shelby T2 - AGRONOMY JOURNAL AB - Nitrogen decision making and the selection of the “right” N rate in wheat ( Triticum aestivum L.) and maize ( Zea mays L.) are difficult due to complex interactions in the N cycle with weather, management, and genetics. An adaptive management approach utilizing farmer networks and participatory learning was established to refine N rate decisions. On‐farm trials were established to reflect grower N rate with additional treatments of ±25% N. In 79 site‐years of wheat, N −25% , N std , and N +25% rate treatments were best in 37, 35, and 28% of the trials, respectively. In 100 site‐years of maize, N −25% , N std , and N +25% rate treatments were best in 58, 30, and 12% of the trials, respectively. Grower’s selected N rates in wheat were similar to recommendations from the North Carolina Realistic Yield Expectation (RYE) database while maize N rates were an average 48 kg ha −1 higher; however, N −25% rates, which were best 58% of the time, were similar to RYE N rate. Doppler‐based estimates of total precipitation from the National Weather Center explained 90% of the average maize yield variability. However, site‐yield was independent of location, N rate, and total precipitation. Measures of performance (N factor productivity and N balance) varied with achieved yields but indicate most growers apply N adequate to maintain organic N lost through mineralization. Results suggest that improved approaches to N rate selection and N efficiency will likely require in‐season adjustments to yield‐based N rates that incorporate local management and environmental conditions throughout the growing season. Core Ideas Yield level and response is independent of location, N rate, and total precipitation. Doppler‐based rainfall estimates help explain seasonal trends in yield. Growers often select N rates greater than recommended for maize but not wheat. DA - 2019/// PY - 2019/// DO - 10.2134/agronj2019.04.0286 VL - 111 IS - 5 SP - 2558-2568 SN - 1435-0645 ER - TY - JOUR TI - A Framework for Evaluating Field-Based, High-Throughput Phenotyping Systems: A Meta-Analysis AU - Young, Sierra N. T2 - SENSORS AB - This paper presents a framework for the evaluation of system complexity and utility and the identification of bottlenecks in the deployment of field-based, high-throughput phenotyping (FB-HTP) systems. Although the capabilities of technology used for high-throughput phenotyping has improved and costs decreased, there have been few, if any, successful attempts at developing turnkey field-based phenotyping systems. To identify areas for future improvement in developing turnkey FB-HTP solutions, a framework for evaluating their complexity and utility was developed and applied to total of 10 case studies to highlight potential barriers in their development and adoption. The framework performs system factorization and rates the complexity and utility of subsystem factors, as well as each FB-HTP system as a whole, and provides data related to the trends and relationships within the complexity and utility factors. This work suggests that additional research and development are needed focused around the following areas: (i) data handling and management, specifically data transfer from the field to the data processing pipeline, (ii) improved human-machine interaction to facilitate usability across multiple users, and (iii) design standardization of the factors common across all FB-HTP systems to limit the competing drivers of system complexity and utility. This framework can be used to evaluate both previously developed and future proposed systems to approximate the overall system complexity and identify areas for improvement prior to implementation. DA - 2019/8/20/ PY - 2019/8/20/ DO - 10.3390/s19163582 VL - 19 IS - 16 SP - SN - 1424-8220 UR - https://doi.org/10.3390/s19163582 KW - systems analysis KW - human-machine interaction KW - complexity analysis KW - technology adoption ER - TY - JOUR TI - Hydrodynamic effects on oyster aquaculture systems: a review AU - Campbell, Matthew D. AU - Hall, Steven G. T2 - REVIEWS IN AQUACULTURE AB - Abstract Hydrodynamics (i.e. interactions of fluid motion with solid bodies) affect oyster aquaculture within every phase of farming. Although it has many direct and indirect implications to the success of any particular aquaculture endeavour, hydrodynamics is the least understood of environmental factors affecting oyster growth. As the industry continues to mature, it is imperative that the influence of hydrodynamics on oyster aquaculture is thoroughly understood. Hydrodynamics also interacts with other environmental factors, such as salinity, temperature, turbidity, food supply and oxygen, which affect the health and growth of oysters through mixing and transport. Proper siting and management of aquaculture requires a comprehensive understanding of the hydrodynamics involved and its impact on the culture of oysters. Unfortunately, literature is inconsistent on oyster feeding and growth response to the influence of hydrodynamics. Feeding and growth limiting velocities are reported that range from 1 to above 22 cm s −1 . This is in contrast with thriving oyster reefs in a natural setting that exist and thrive above 15 cm s −1 . Upweller systems have reported bulk velocities that range from 0.5 to 7.1 cm s −1 . In practice, higher current velocities are desirable because they increase delivery of food to the oysters, improve water quality, and enhance dispersal of biodeposits. This paper summarizes the findings of those studies in regard to hydrodynamics and provides suggestions for future work. DA - 2019/8// PY - 2019/8// DO - 10.1111/raq.12271 VL - 11 IS - 3 SP - 896-906 SN - 1753-5131 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85050378575&partnerID=MN8TOARS KW - aquaculture KW - flow KW - hydrodynamics KW - oyster KW - upweller KW - velocity ER - TY - JOUR TI - Catalysts evaluation for production of hydrogen gas and carbon nanotubes from the pyrolysis-catalysis of waste tyres AU - Li, Wenping AU - Wei, Mimi AU - Liu, Yunquan AU - Ye, Yueyuan AU - Li, Shuirong AU - Yuan, Wenqiao AU - Wang, Meng AU - Wang, Duo T2 - INTERNATIONAL JOURNAL OF HYDROGEN ENERGY AB - Six different types of catalysts (nickel, iron, and cobalt each supported by γ-Al2O3 and activated carbon) that were prepared via impregnation were used to produce hydrogen (H2) and carbon nanotubes (CNTs) from the pyrolytic product of waste tyres. A two-stage pyrolytic-catalytic reactor was constructed, in which the waste tyre was pyrolyzed in the first pyrolysis reactor, and the resultant pyrolysis vapors underwent the reforming and upgrading step in the downstream catalytic reactor. The results showed that the interaction between the active metal and its support had a remarkable effect on the production of H2 and CNTs. Compared with the series of γ-Al2O3 supported catalysts, all the activated carbon-supported catalysts showed higher H2 yields and better CNTs quality. For the same catalyst support (γ-Al2O3 or activated carbon), the higher yield of H2 and better quality of CNTs were obtained by the Ni catalysts, followed by the Fe catalysts and the Co catalysts. Among all the catalysts, Ni supported by activated carbon exhibited the best catalytic performance, producing the highest hydrogen yield (59.55 vol.%) and the best CNT quality. Further investigation about the influence of CH4 and naphthalene as the carbon source on generated CNTs revealed that CH4 led to longer CNT length and higher graphitization than naphthalene. DA - 2019/7/26/ PY - 2019/7/26/ DO - 10.1016/j.ijhydene.2019.05.204 VL - 44 IS - 36 SP - 19563-19572 SN - 1879-3487 KW - Waste tyre KW - Pyrolysis KW - Hydrogen KW - Carbon nanotubes KW - Ni/AC ER - TY - JOUR TI - Urbanization focuses carnivore activity in remaining natural habitats, increasing species interactions AU - Parsons, Arielle W. AU - Rota, Christopher T. AU - Forrester, Tavis AU - Baker-Whatton, Megan C. AU - McShea, William J. AU - Schuttler, Stephanie G. AU - Millspaugh, Joshua J. AU - Kays, Roland T2 - JOURNAL OF APPLIED ECOLOGY AB - Abstract Interspecific interactions can provoke temporal and spatial avoidance, ultimately affecting population densities and spatial distribution patterns. The ability (or inability) of species to coexist has consequences for diversity and ultimately ecosystem stability. Urbanization is predicted to change species interactions but its relative impact is not well known. Urbanization gradients offer the opportunity to evaluate the effect of humans on species interactions by comparing community dynamics across levels of disturbance. We used camera traps deployed by citizen scientists to survey mammals along urbanization gradients of two cities (Washington, DC and Raleigh, NC, USA). We used a multispecies occupancy model with four competing predator species to test whether forest fragmentation, interspecific interactions, humans or prey had the greatest influence on carnivore distribution. Our study produced 6,413 carnivore detections from 1,260 sites in two cities, sampling both private and public lands. All species used all levels of the urbanization gradient to a similar extent, but co‐occurrence of urban‐adapted foxes with less urban‐adapted bobcats and coyotes was dependent on the availability of green space, especially as urbanization increased. This suggests green space allows less urban‐adapted species to occupy suburban areas, but focuses their movements through remaining forest patches, leading to more species interactions. Synthesis and applications . Species interactions, forest fragmentation and human‐related covariates were important determinants of carnivore occupancy across a gradient of urbanization with the relative importance of forest fragmentation being highest. We found evidence of both positive and negative interactions across the gradient with some dependent on available green space, suggesting that fragmentation leads to higher levels of spatial interaction. Where green space is adequate, there appears to be sufficient opportunity for coexistence between carnivore species in an urban landscape. DA - 2019/8// PY - 2019/8// DO - 10.1111/1365-2664.13385 VL - 56 IS - 8 SP - 1894-1904 SN - 1365-2664 KW - camera traps KW - carnivore KW - citizen science KW - distribution KW - green space KW - occupancy KW - species interactions KW - urbanization ER - TY - JOUR TI - Phosphorus and Soil Health Management Practices AU - Duncan, Emily W. AU - Osmond, Deanna L. AU - Shober, Amy L. AU - Starr, Laura AU - Tomlinson, Peter AU - Kovar, John L. AU - Moorman, Thomas B. AU - Peterson, Heidi M. AU - Fiorellino, Nicole M. AU - Reid, Keith T2 - AGRICULTURAL & ENVIRONMENTAL LETTERS AB - Core Ideas Trade‐offs exist in nutrient losses for soil health management. Combining soil health practices and other BMPs can exacerbate or mitigate P losses. There are limitations of soil health practices and reducing P losses. Educators should discuss BMP trade‐offs associated with P loss. Soil health has gained widespread attention in agronomic and conservation communities due to its many purported benefits, including claims that implementation of core soil health practices (e.g., conservation tillage, cover crops) will improve water quality by curtailing runoff losses of nutrients such as phosphorus (P). However, a review of the existing literature points to well‐established findings regarding trade‐offs in water quality outcomes following the implementation of core soil health practices. In fact, both conservation tillage and cover crops can exacerbate dissolved P losses, undermining other benefits such as reductions in particulate P (sediment‐bound P) losses. Soil health management must be pursued in a manner that considers the complex interaction of nutrient cycling processes and produces realistic expectations. Achieving water quality goals through soil health practices will require adaptive management and continued, applied research to support evidence‐based farm management decisions. DA - 2019/7/25/ PY - 2019/7/25/ DO - 10.2134/ael2019.04.0014 VL - 4 IS - 1 SP - SN - 2471-9625 ER - TY - JOUR TI - Consumer Perception of Skinning Injury in Sweetpotatoes and Implications for Marketability: An Experimental Auction AU - Collort, Alba J. AU - Meyers, Stephen L. AU - Ward, Jason K. T2 - HORTTECHNOLOGY AB - Skinning of sweetpotato ( Ipomoea batatas ) storage roots is one of the greatest concerns of sweetpotato producers. Although skinning injury is very common, the severity of the injury can vary widely. At an undefined threshold, sweetpotatoes with skinning injury are no longer sold for fresh consumption. The objectives of this study were to examine how skinning injury influences consumers’ willingness-to-pay (WTP) for sweetpotatoes and to identify differences in valuations when the extent of skinning injury is labeled. Image analysis was used to quantify skinning injury and then an incentive-compatible, nonhypothetical laboratory experimental auction was conducted to collect data on consumers’ WTP for five categories of sweetpotatoes: 0% to <1% skinning injury, 1.0% to 3.0%, 3.1% to 5.0%, 5.1% to 7.5%, and 7.6% to 10.0%. On average, consumers were willing to pay the most for sweetpotatoes with 0% to <1% skinning injury (up to $1.51/lb to $1.67/lb) and the least for sweetpotatoes with 7.6% to 10% (up to $0.76/lb to $0.85/lb), yet mean WTP values were nonzero for all skinning levels. Moreover, when the extent of skinning was labeled (relative to when they bid blindly), consumers were willing to pay price premiums for sweetpotatoes with low skinning injury levels (0% to 5%) and discounted sweetpotatoes with the highest skinning injury level (7.6% to 10.0%), suggesting that skinning levels of 7.6% and above may not be acceptable by consumers. DA - 2019/8// PY - 2019/8// DO - 10.21273/HORTTECH04355-19 VL - 29 IS - 4 SP - 468-475 SN - 1943-7714 KW - Ipomoea batatas KW - willingness-to-pay ER - TY - JOUR TI - Evaluating the Hydrologic Benefits of a Bioswale in Brunswick County, North Carolina (NC), USA AU - Purvis, Rebecca A. AU - Winston, Ryan J. AU - Hunt, William F. AU - Lipscomb, Brian AU - Narayanaswamy, Karthik AU - McDaniel, Andrew AU - Lauffer, Matthew S. AU - Libes, Susan T2 - WATER AB - Bioswales are a promising stormwater control measure (SCM) for roadway runoff management, but few studies have assessed performance on a field scale. A bioswale is a vegetated channel with underlying engineered media and a perforated underdrain to promote improved hydrologic and water quality treatment. A bioswale with a rip-rap lined forebay was constructed along state highway NC 211 in Bolivia, North Carolina, USA, and monitored for 12 months. Thirty-seven of the 39 monitored rain events exfiltrated into underlying soils, resulting in no appreciable overflow or underdrain volume. The bioswale completely exfiltrated a storm event of 86.1 mm. The one event to have underdrain-only flow was 4.8 mm. The largest and third-largest rainfall depth events (82.6 and 146 mm, respectively) had a large percentage (85%) of volume exfiltrated, but also had appreciable overflow and underdrain volumes exiting the bioswale, resulting in no peak flow mitigation. Overall, this bioswale design was able to capture and manage storms larger than the design storm (38 mm), showing the positive hydrologic performance that can be achieved by this bioswale. The high treatment capabilities were likely due to the high infiltration rate of the media and the underlying soil, longer forebay underlain with media, gravel detention layer with an underdrain, and shallow slope. DA - 2019/6// PY - 2019/6// DO - 10.3390/w11061291 VL - 11 IS - 6 ER - TY - JOUR TI - Coordinated management of organic waste and derived products AU - Sampat, Apoorva M. AU - Hu, Yicheng AU - Sharara, Mahmoud AU - Aguirre-Villegas, Horacio AU - Ruiz-Mercado, Gerardo AU - Larson, Rebecca A. AU - Zavala, Victor M. T2 - COMPUTERS & CHEMICAL ENGINEERING AB - We propose a coordination framework for managing urban and rural organic waste in a scalable manner by orchestrating waste exchange, transportation, and transformation into value-added products. The framework is inspired by coordinated management systems that are currently used to operate power grids across the world and that have been instrumental in achieving high levels of efficiency and technological innovation. In the proposed framework, suppliers and consumers of waste and derived products as well as transportation and technology providers bid into a coordination system that is operated by an independent system operator. Allocations and prices for waste and derived products are obtained by the operator by solving a dispatch problem that maximizes the social welfare and that balances supply and demand across a given geographical region. Coordination enables handling of complex constraints and interdependencies that arise from transportation and bio-physico-chemical transformations of waste into products. We prove that the coordination system delivers prices and product allocations that satisfy economic and efficiency properties of a competitive market. The framework is scalable in that it can provide open access that fosters transactions between small and large players in urban and rural areas and over wide geographical regions. Moreover, the framework provides a systematic approach to enable coordinated responses to externalities such as droughts and extreme weather events, to monetize environmental impacts and remediation, to achieve complex social goals such as geographical nutrient balancing, and to justify technology investment and development efforts. Furthermore, the framework can facilitate coordination with electrical, natural gas, water, transportation, and food distribution infrastructures. DA - 2019/9/2/ PY - 2019/9/2/ DO - 10.1016/j.compchemeng.2019.06.008 VL - 128 SP - 352-363 SN - 1873-4375 KW - Organic waste KW - Markets KW - Coordination KW - Interdependencies ER - TY - JOUR TI - A maize polygalacturonase functions as a suppressor of programmed cell death in plants AU - He, Yijian AU - Karre, Shailesh AU - Johal, Gurmukh S. AU - Christensen, Shawn A. AU - Balint-Kurti, Peter T2 - BMC Plant Biology AB - The hypersensitive defense response (HR) in plants is a fast, localized necrotic response around the point of pathogen ingress. HR is usually triggered by a pathogen recognition event mediated by a nucleotide-binding site, leucine-rich repeat (NLR) protein. The autoactive maize NLR gene Rp1-D21 confers a spontaneous HR response in the absence of pathogen recognition. Previous work identified a set of loci associated with variation in the strength of Rp1-D21-induced HR. A polygalacturonase gene homolog, here termed ZmPGH1, was identified as a possible causal gene at one of these loci on chromosome 7. Expression of ZmPGH1 inhibited the HR-inducing activity of both Rp1-D21 and that of another autoactive NLR, RPM1(D505V), in a Nicotiana benthamiana transient expression assay system. Overexpression of ZmPGH1 in a transposon insertion line of maize was associated with suppression of chemically-induced programmed cell death and with suppression of HR induced by Rp1-D21 in maize plants grown in the field. ZmPGH1 functions as a suppressor of programmed cell death induced by at least two autoactive NLR proteins and by two chemical inducers. These findings deepen our understanding of the control of the HR in plants. DA - 2019/7/15/ PY - 2019/7/15/ DO - 10.1186/s12870-019-1897-5 VL - 19 IS - 1 SP - J2 - BMC Plant Biol LA - en OP - SN - 1471-2229 UR - http://dx.doi.org/10.1186/s12870-019-1897-5 DB - Crossref KW - Hypersensitive response KW - Maize KW - Polygalacturonase ER - TY - JOUR TI - Modeling Internal Erosion Processes in Soil Pipes: Capturing Geometry Dynamics AU - Nieber, J.L. AU - Wilson, G.V. AU - Fox, G.A. T2 - Vadose Zone Journal AB - Core Ideas Soil pipes are important features contributing to nonuniform flow in the vadose zone. Soil pipe flow and internal erosion is modeled with coupled flow and transport equations. Modeling results compare favorably to experimental measurements. The flow of water in a soil pipe and the resulting erosion of the soil pipe wall is simulated using a numerical solution of the Reynolds‐averaged Navier–Stokes equations coupled with the well‐known linear excess shear stress equation and the governing equation for transport of suspended sediment in turbulent flow. The modeling results are compared with an experiment in which the entrance to the soil pipe constructed in a laboratory flume was subjected to a constant head of water in a reservoir. The modeled pipe discharge was in good agreement with the measured results when roughness was imposed on the pipe wall. The temporal growth of the soil pipe was in good agreement with the experimental results when using a soil erodibility coefficient of 0.0025 s/m. Several assumptions were made in model formulation, the most significant being that the soil pipe grows uniformly along its length and that no sediment deposition occurs. Recommendations for future work regarding these assumptions as well as others are discussed. DA - 2019/// PY - 2019/// DO - 10.2136/vzj2018.09.0175 VL - 18 IS - 1 SP - 0 LA - en OP - SN - 1539-1663 UR - http://dx.doi.org/10.2136/vzj2018.09.0175 DB - Crossref ER - TY - JOUR TI - Tidal Marsh Creation AU - Broome, Stephen W. AU - Craft, Christopher B. AU - Burchell, Michael R. T2 - COASTAL WETLANDS: AN INTEGRATED ECOSYSTEM APPROACH, 2ND EDITION AB - Salt and brackish water tidal marshes are productive wetlands that provide ecosystem services including habitat, food energy for the estuarine food web, maintenance of water quality, storage of storm water, buffering storm waves and reducing shoreline erosion, carbon sequestration, and socioeconomic benefits. Loss of tidal marshes occurs as a result of dredging, filling, tidal restrictions, subsidence, sea level rise, and erosion. To mitigate those losses, techniques have been developed to create marshes on sites where they did not previously exist. The goal of tidal marsh creation is to provide habitats similar in structure and function to natural marshes. Because tides are the controlling abiotic factor of tidal marshes, the most critical requirement for creating new marshes is constructing sites at the correct elevation relative to the local tidal regime. Other important site-related factors that must be considered to insure successful marsh creation are slope, drainage, wave climate, currents, salinity, and soil physicochemical properties. Cultural practices that are important to establishment of vegetation include selection of native plant species, seed collection and storage, seedling production, site preparation, soil testing, fertilization, handling of transplants, timing of planting, plant spacing, control of undesirable invasive plants, and maintenance until the marsh is self-sustaining. The criteria used to define successful tidal marsh creation are often controversial. Plant communities may be equivalent to natural reference marshes in a few years, whereas other characteristics, such as soil organic matter, and numbers and species of benthic invertebrates require much longer to reach equivalence. When marsh creation technology is properly applied, tidal marshes can be created that provide many of the same ecosystems services that are provided by natural systems. DA - 2019/// PY - 2019/// DO - 10.1016/B978-0-444-63893-9.00022-8 SP - 789-816 ER - TY - JOUR TI - The plant hypersensitive response: concepts, control and consequences AU - Balint‐Kurti, Peter T2 - Molecular Plant Pathology AB - Summary The hypersensitive defence response is found in all higher plants and is characterized by a rapid cell death at the point of pathogen ingress. It is usually associated with pathogen resistance, though, in specific situations, it may have other consequences such as pathogen susceptibility, growth retardation and, over evolutionary timescales, speciation. Due to the potentially severe costs of inappropriate activation, plants employ multiple mechanisms to suppress inappropriate activation of HR and to constrain it after activation. The ubiquity of this response among higher plants despite its costs suggests that it is an extremely effective component of the plant immune system. DA - 2019/7/15/ PY - 2019/7/15/ DO - 10.1111/mpp.12821 VL - 20 IS - 8 SP - 1163-1178 J2 - Molecular Plant Pathology LA - en OP - SN - 1464-6722 1364-3703 UR - http://dx.doi.org/10.1111/mpp.12821 DB - Crossref KW - hypersensitive response ER - TY - JOUR TI - Microfibers generated from the laundering of cotton, rayon and polyester based fabrics and their aquatic biodegradation AU - Zambrano, Marielis C. AU - Pawlak, Joel J. AU - Daystar, Jesse AU - Ankeny, Mary AU - Cheng, Jay J. AU - Venditti, Richard A. T2 - MARINE POLLUTION BULLETIN AB - The effect of fiber type (cotton, polyester, and rayon), temperature, and use of detergent on the number of microfibers released during laundering of knitted fabrics were studied during accelerated laboratory washing (Launder-Ometer) and home laundering experiments. Polyester and cellulose-based fabrics all shed significant amounts of microfibers and shedding levels were increased with higher water temperature and detergent use. Cellulose-based fabrics released more microfibers (0.2–4 mg/g fabric) during accelerated laundering than polyester (0.1–1 mg/g fabric). Using well-controlled aquatic biodegradation experiments it was shown that cotton and rayon microfibers are expected to degrade in natural aquatic aerobic environments whereas polyester microfibers are expected to persist in the environment for long periods of time. DA - 2019/5// PY - 2019/5// DO - 10.1016/j.marpolbul.2019.02.062 VL - 142 SP - 394-407 SN - 1879-3363 KW - Microplastics KW - Microfibers KW - Laundering KW - Biodegradation KW - Textiles KW - Aquatic environments ER - TY - JOUR TI - Classifying the nocturnal atmospheric boundary layer into temperature and flow regimes AU - Pfister, Lena AU - Lapo, Karl AU - Sayde, Chadi AU - Selker, John AU - Mahrt, Larry AU - Thomas, Christoph K. T2 - QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY AB - We propose a classification scheme for nocturnal atmospheric boundary layers and apply it to investigate the spatio‐temporal structure of air temperature and wind speed in a shallow valley during the Shallow Cold Pool Experiment. This field campaign was the first to collect spatially continuous temperature and wind information at high resolution (1 s, 0.25 m) using the distributed temperature sensing technique across a 220 m long transect at three heights (0.5, 1.0, 2.0 m). The night‐time classification scheme was motivated by a surface energy balance and used a combination of static stability, wind regime and longwave radiative forcing as quantities to determine physically meaningful boundary‐layer regimes. Out of all potential combinations of these three quantities, 14 night‐time classes contained observations, of which we selected three for detailed analysis and comparison. The three classes represent a transition from mechanical to radiative forcing. The first night class represents conditions with strong dynamic forcing caused by locally induced lee turbulence dominating near‐surface temperatures across the shallow valley. The second night class was a concurrence of enhanced dynamic mixing due to significant winds at the valley shoulders and cold‐air pooling at the bottom of the shallow valley as a result of strong radiative cooling. The third night class was characteristic of weak winds eliminating the impact of mechanical mixing but emphasizing the formation and pooling of cold air at the valley bottom. The proposed night‐time classification scheme was found to sort the experimental data into physically meaningful regimes of surface flow and transport. It is suitable to stratify short‐ and long‐term experimental data for ensemble averaging and to identify case studies. DA - 2019/4// PY - 2019/4// DO - 10.1002/qj.3508 VL - 145 IS - 721 SP - 1515-1534 SN - 1477-870X KW - classification KW - distributed temperature sensing KW - nocturnal near-surface temperatures KW - radiative forcing KW - stable boundary layer KW - topography KW - Taylor's hypothesis ER - TY - JOUR TI - Maize meal slurry mixing: an economical recipe for precise aflatoxin quantitation AU - Kumphanda, J. AU - Matumba, L. AU - Whitaker, T. B. AU - Kasapila, W. AU - Sandahl, J. T2 - WORLD MYCOTOXIN JOURNAL AB - The laboratory sample preparation for mycotoxin determination in cereals, often overlooked among sampling plans and analytical methods, was further studied. The precision of aflatoxin analysis in comminuted maize samples using 25 g slurry (prepared from 250 g test portion of comminuted maize, water/matrix (1+1, v/w)) and 12.5 g dry grind test portion were compared against the conventional 50 g dry grind test portion through replicated (10) Aflatest® immunoaffinity fluorometric tests of naturally contaminated samples with aflatoxin concentration ranging from 4.9 to 81.7 μg/kg. The overall mean aflatoxin concentration obtained from the 10 different samples tested using 12.5 g and 50.0 g dry grind procedures was 12% significantly (P<0.05) lower (poorer) compared to 25 g slurry. The sample preparation plus analytical variance associated with testing 25.0 g slurry, 50.0 g dry grind and 12.5 g dry grind test portions were in the ratio of 1:5:15, respectively. DA - 2019/// PY - 2019/// DO - 10.3920/WMJ2018.2415 VL - 12 IS - 3 SP - 203-212 SN - 1875-0796 KW - dry grind KW - slurry mixing KW - sample preparation KW - aflatoxin analysis KW - maize KW - precision KW - recovery ER - TY - JOUR TI - Overcoming cellulose recalcitrance in woody biomass for the lignin-first biorefinery AU - Yang, Haibing AU - Zhang, Ximing AU - Luo, Hao AU - Liu, Baoyuan AU - Shiga, Tania M. AU - Li, Xu AU - Kim, Jeong Im AU - Rubinelli, Peter AU - Overton, Jonathan C. AU - Subramanyam, Varun AU - Cooper, Bruce R. AU - Mo, Huaping AU - Abu-Omar, Mahdi M. AU - Chapple, Clint AU - Donohoe, Bryon S. AU - Makowski, Lee AU - Mosier, Nathan S. AU - McCann, Maureen C. AU - Carpita, Nicholas C. AU - Meilan, Richard T2 - BIOTECHNOLOGY FOR BIOFUELS AB - Low-temperature swelling of cotton linter cellulose and subsequent gelatinization in trifluoroacetic acid (TFA) greatly enhance rates of enzymatic digestion or maleic acid-AlCl3 catalyzed conversion to hydroxymethylfurfural (HMF) and levulinic acid (LA). However, lignin inhibits low-temperature swelling of TFA-treated intact wood particles from hybrid poplar (Populus tremula × P. alba) and results in greatly reduced yields of glucose or catalytic conversion compared to lignin-free cellulose. Previous studies have established that wood particles from transgenic lines of hybrid poplar with high syringyl (S) lignin content give greater glucose yields following enzymatic digestion.Low-temperature (- 20 °C) treatment of S-lignin-rich poplar wood particles in TFA slightly increased yields of glucose from enzymatic digestions and HMF and LA from maleic acid-AlCl3 catalysis. Subsequent gelatinization at 55 °C resulted in over 80% digestion of cellulose in only 3 to 6 h with high-S-lignin wood, compared to 20-60% digestion in the wild-type poplar hybrid and transgenic lines high in guaiacyl lignin or 5-hydroxy-G lignin. Disassembly of lignin in woody particles by Ni/C catalytic systems improved yields of glucose by enzymatic digestion or catalytic conversion to HMF and LA. Although lignin was completely removed by Ni/C-catalyzed delignification (CDL) treatment, recalcitrance to enzymatic digestion of cellulose from the high-S lines was reduced compared to other lignin variants. However, cellulose still exhibited considerable recalcitrance to complete enzymatic digestion or catalytic conversion after complete delignification. Low-temperature swelling of the CDL-treated wood particles in TFA resulted in nearly complete enzymatic hydrolysis, regardless of original lignin composition.Genetic modification of lignin composition can enhance the portfolio of aromatic products obtained from lignocellulosic biomass while promoting disassembly into biofuel and bioproduct substrates. CDL enhances rates of enzymatic digestion and chemical conversion, but cellulose remains intrinsically recalcitrant. Cold TFA is sufficient to overcome this recalcitrance after CDL treatment. Our results inform a 'no carbon left behind' strategy to convert total woody biomass into lignin, cellulose, and hemicellulose value streams for the future biorefinery. DA - 2019/6/29/ PY - 2019/6/29/ DO - 10.1186/s13068-019-1503-y VL - 12 SP - SN - 1754-6834 KW - Cellulose KW - Lignin KW - Recalcitrance KW - Catalysis KW - Delignification KW - Poplar ER - TY - JOUR TI - Influences of Catchment and River Channel Characteristics on the Magnitude and Dynamics of Storage and Re-Suspension of Fine Sediments in River Beds AU - Park, Jungsu AU - Batalla, Ramon J. AU - Birgand, Francois AU - Esteves, Michel AU - Gentile, Francesco AU - Harrington, Joseph R. AU - Navratil, Oldrich AU - López-Tarazón, Jose Andres AU - Vericat, Damià T2 - Water AB - Fine particles or sediments are one of the important variables that should be considered for the proper management of water quality and aquatic ecosystems. In the present study, the effect of catchment characteristics on the performance of an already developed model for the estimation of fine sediments dynamics between the water column and sediment bed was tested, using 13 catchments distributed worldwide. The model was calibrated to determine two optimal model parameters. The first is the filtration parameter, which represents the filtration of fine sediments through pores of the stream bed during the recession period of a flood event. The second parameter is the bed erosion parameter that represents the active layer, directly related to the re-suspension of fine sediments during a flood event. A dependency of the filtration parameter with the catchment area was observed in catchments smaller than ~100 km2, whereas no particular relationship was observed for larger catchments (>100 km2). In contrast, the bed erosion parameter does not show a noticeable dependency with the area or other environmental characteristics. The model estimated the mass of fine sediments released from the sediment bed to the water column during flood events in the 13 catchments within ~23% bias. DA - 2019/4/26/ PY - 2019/4/26/ DO - 10.3390/w11050878 VL - 11 IS - 5 SP - 878 SN - 2073-4441 UR - https://www.mdpi.com/2073-4441/11/5/878 KW - bed erosion KW - catchment area KW - filtration KW - sediment accumulation KW - sediment bed fluidization KW - sediment re-suspension ER - TY - JOUR TI - Undergraduate Perceptions of Climate Education Exposure in Natural Resources Management AU - Nelson, Natalie G. AU - Montefiore, Lise AU - Anthony, Cord AU - Merriman, Laura AU - Kuster, Emma AU - Fox, Garey A. T2 - Transactions of the ASABE AB - Abstract. To meet rising demands for climate-literate workers, undergraduate courses and curricula will require updates so that students are afforded opportunities to engage in climate science education. Previous research on undergraduate climate education has primarily focused on evaluating whether students have grounding in essential climate science principles, but these studies fail to capture the degree to which students feel they are exposed to climate education in their undergraduate programs and courses. In this study, we characterize recent trends in undergraduates’ perceived exposure to climate education across the U.S. by analyzing responses to a national survey of graduate students who attended undergraduate institutions in the U.S. (n = 423). Survey respondents scored the levels of exposure that they received to a variety of climatological topics during their undergraduate studies, which ranged from applied (e.g., earth observations, numerical modeling) to interdisciplinary (e.g., agricultural climatology, hydroclimatology) and specialized (e.g., boundary-layer climatology). Our results reveal that those who received bachelor’s degrees from programs related to human dimensions of natural resources management (e.g., geography, resource economics) generally felt that their undergraduate curricula provided them with exposure to climate education, whereas those who graduated from programs in engineering and the agricultural and life sciences largely reported a lack of climate coverage in their undergraduate studies. Students of all disciplinary backgrounds indicated that they received poor exposure to numerical modeling of historical and future climatic conditions. Findings from this study underline key areas in which curricular or course improvements are needed to ensure that future decision-makers are confident in their practical use of climate science. Keywords: Climate change, Climate science, Natural resources management, Postsecondary education, Undergraduate education, United States. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13361 VL - 62 IS - 3 SP - 831-839 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13361 DB - Crossref KW - Climate change KW - Climate science KW - Natural resources management KW - Postsecondary education KW - Undergraduate education KW - United States ER - TY - JOUR TI - Effects of Co-occurring Species Present in Swine Lagoons on Adsorption of Copper on Eggshell AU - Hess, Brianna J. AU - Kolar, Praveen AU - Classen, John J. AU - Knappe, Detlef AU - Cheng, Jay J. T2 - INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH DA - 2019/8// PY - 2019/8// DO - 10.1007/s41742-019-00203-x VL - 13 IS - 4 SP - 613-622 SN - 2008-2304 KW - Adsorption KW - Eggshell KW - Copper KW - Swine lagoons KW - Acetate KW - Ammonia ER - TY - JOUR TI - Featured Collection Introduction: The Emerging Science of Aquatic System Connectivity II AU - Smith, Lora L. AU - Jones, C. Nathan AU - Nelson, Natalie G. T2 - JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AB - The science of aquatic systems connectivity has developed rapidly over the past 20 years (Jones, Nelson, et al. 2019). Research spans the different forms and functions of connectivity (hydrologic, biogeochemical, and biological) at vastly different spatial scales and hydrologic settings (Larsen et al. 2012; Bracken et al. 2013; Harvey and Gooseff 2015; U.S. Environmental Protection Agency 2015; Cohen et al. 2016; Covino 2017; Fritz et al. 2018; Wohl et al. 2019). This collection, The Emerging Science of Aquatic Systems Connectivity II, includes eight papers focused on aquatic system connectivity and follows the featured collection The Emerging Science of Aquatic Systems Connectivity I (Jones, Nelson, et al. 2019). The papers in both collections are products of the 2017 American Water Resources (AWRA) Specialty Conference, Connecting the Dots: The Emerging Science of Aquatic System Connectivity, which took place in May 2017 in Snowbird, Utah. The conference consisted of 33 technical sessions with over 140 presenters and with this most recent collection produced a total of 19 papers. As with Collection I, these papers increase our understanding of the functions of aquatic systems and include novel modeling approaches to characterizing connectivity and contribute to management and restoration of these functions. Three papers in this issue used modeling approaches to examine the hydrologic role of wetlands at the landscape scale. Ameli and Creed (2019) modeled effects of wetland location relative to stream networks on flows during floods and droughts in the Nose Creek watershed of the Prairie Pothole Region. Their model combined historical, existing, and drained wetlands in the watershed to estimate the hydrological functions of wetlands located at different distances from the main stream network. They found wetlands close to the main stream network play a disproportionately important role in attenuating peakflow, but wetland location is less important for regulating baseflow. These findings can help managers prioritize wetland restoration efforts for flood or drought risk mitigation. Green et al. (2019) modeled the runoff storage potential of drained upland depressions on the Des Moines Lobe of Iowa using hydrologically enforced Light Detection and Ranging (LIDAR)-derived Digital Elevation Models and a unique geoprocessing algorithm to determine storage capacities. In contrast to Ameli and Creed (2019), Green et al. (2019) determined the drained upland depressions in this region have insufficient storage capacity to significantly alter regional and local flood events. Jones, Ameli, et al. (2019) review the current capabilities of hydrologic models and their ability to simulate hydrologic connectivity of non-floodplain wetlands. They present four distinct case studies that employ process-based models which vary in complexity, spatial representation of hydrologic processes, and fidelity (i.e., the models ability to faithfully represent reality). Jones, Ameli, et al. (2019) ends with a synthesis of five best modeling practices to guide future model application and development. Bieger et al. (2019) used the Soil & Water Assessment Tool (SWAT)+ model to represent connectivity of upland areas to floodplains and streams. They tested the concept of incorporating hydrologic connectivity in watershed models, which improves the simulation of processes controlling the response of watersheds to rainfall events. A realistic representation of connectivity in watershed models has important implications for the identification of pollution sources and sinks. Follstad Shah et al. (2019) addressed implications of connectivity on water quality. They quantified proportional inputs and the magnitude of discharge associated with natural and engineered sources of water in a semiarid urban river system. Authors used synoptic sampling of water isotopes and both a Bayesian mixing model framework and a separate hydrological mass balance approach to quantify spatial and temporal variation in water sources. They found spatiotemporal variability in water sources controls chemical and physical properties of the river system. One paper considered the role of connectivity on ecosystem function. Blersch et al. (2019) propose a new metric, called metabolic variance, to detect changes in a stream's primary productivity and respiration as a result of restoration. Metabolic variance uses stream metabolism to assess how restoration-driven changes to instream hydraulics translate into shifts in ecosystem function. Two papers used modeling to assess connectivity among habitats for rare fauna. Caruso et al. (2019) used hydrodynamic modeling to facilitate restoration of connections between the Green River and floodplain wetlands for endangered fish species recovery at Ouray National Wildlife Refuge in Utah. Zaffaroni et al. (2019) used geospatial analysis and remote sensing to assess wetland networks (wetlandscapes) and habitat quality to improve conservation outcomes for threatened amphibian species which rely on different wetland, stream, and upland habitats to complete their life cycle. Both wetland habitat quality and connectivity act jointly but differently on amphibian population dynamics and should both be considered when managing wetlandscapes. Combined, the two featured collections on The Emerging Science of Aquatic System Connectivity add 19 papers to the growing body of aquatic system science literature. These papers are representative of the depth and breadth of this growing interdisciplinary community, where studies span spatial scales (i.e., individual wetlands to watersheds), hydrologic units (e.g., upland wetlands to downstream waters and natural to engineered systems), and the many dimensions of connectivity (i.e., physical, chemical, ecological, and biological). In this second featured collection, papers focused on modeling aquatic system connectivity of both upland and floodplain wetlands, and examining the role of connectivity on water quality and biological function. In the coming decades, managing and restoring our aquatic systems will continue to be a grand challenge, and the community of researchers investigating aquatic system connectivity must continue to provide actionable and science-based solutions to meet those challenges. This collection is an effort aimed at fostering an interdisciplinary dialogue on how best to address aquatic system connectivity concerns for restoring and managing our ecosystems. We thank Heather Golden, Charles Lane, and Tamara Newcomer-Johnson (USEPA) for their guidance on this featured collection. The AWRA specialty conference, and this featured collection, would not have been possible without their efforts and those of the AWRA leadership. CNJ is supported by the National Socio-Environmental Synthesis Center under funding received from the National Science Foundation DBI-1052875. NGN is supported by the USDA National Institute of Food and Agriculture, Hatch project 1016068. DA - 2019/6// PY - 2019/6// DO - 10.1111/1752-1688.12760 VL - 55 IS - 3 SP - 526-528 SN - 1752-1688 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85066619383&partnerID=MN8TOARS ER - TY - JOUR TI - Key tomato volatile compounds during postharvest ripening in response to chilling and pre-chilling heat treatments AU - Wang, L. AU - Baldwin, E. AU - Luo, W. AU - Zhao, W. AU - Brecht, J. AU - Bai, J. T2 - POSTHARVEST BIOLOGY AND TECHNOLOGY AB - Mature green ‘FL 47′ tomatoes were exposed to heat (52 °C water for 5 min) and/or cold (5 °C for 4 d) before sampling at following ripening stages. Results showed that although did not cause visual injury, chilling substantially suppressed ripening process, ethylene production and respiration rate at early stages, while a slight impact was observed by heating. Most volatiles were detected at low levels before breaker stage with a burst at red stage in all treatments. Chilling and heating induced production of “green” note volatiles, especially hexenal early in fruit development. At the red stage, 11 out of 12 important aromatic volatiles exhibited significant reduction in chilled fruit compared to control, while most volatiles in heated fruit were recovered during ripening. On the other hand, a pre-chilling heat treatment alleviated the chilling-caused reduction of ethylene during ripening, which was associated with higher levels of 6-methyl-5-hepten-2-one, 2-phenylacetaldehyde, and 2-phenylethanol in red fruit. DA - 2019/8// PY - 2019/8// DO - 10.1016/j.postharvbio.2019.04.013 VL - 154 SP - 11-20 SN - 1873-2356 KW - Solanum lycopersicum KW - Aromatic volatiles KW - Chilling KW - Heating KW - Ethylene production KW - Ripening process ER - TY - JOUR TI - Comparing Four Methods of Measuring Soil Organic Matter in North Carolina Soils AU - Roper, Wayne R. AU - Robarge, Wayne P. AU - Osmond, Deanna L. AU - Heitman, Joshua L. T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - Core Ideas Results of agronomic management effects on SOM are inconsistent among methods. Correlations among methods of measuring SOM differ depending on soil. Soil organic matter content should be compared using similar procedures. Soil organic matter (SOM) provides many beneficial soil ecosystem services for sustainable soil management, but it is unclear how results from different methods of measuring SOM should be compared when making soil management decisions. To compare different methods, we used 84 soil samples from long‐term agronomic trials in the coastal plain, piedmont, and mountain regions of North Carolina. Coastal plain and mountain trials included combinations of tillage and management (conventional vs. organic), whereas piedmont trials were configured to evaluate tillage intensity. The methods used to measure SOM were Walkley‐Black (WB), mass loss on ignition (LOI), automated dry combustion (ADC), and humic matter (HM) colorimetry. Correlations among LOI, WB, and ADC were significant ( p < 0.0001) for SOM measured from the total population of soils, but variability due to location implied that HM had no correlation to other methods. For measures of soil organic carbon compared to SOM, the WB results were biased high compared to ADC, and ADC was more strongly correlated to LOI than WB. When using the methods to evaluate the effects of agronomic management on SOM, results varied for different methods and locations. Conservation management did not consistently accumulate more SOM than other soil management practices, and no method consistently differentiated soils based on management. Variation in the composition of SOM measured using conventional methods may be causing discrepancies in reported changes in SOM content over time. To avoid confusion about how agronomic management affects SOM, assessments should limit comparisons to methodologies with similar measurement protocols. DA - 2019/// PY - 2019/// DO - 10.2136/sssaj2018.03.0105 VL - 83 IS - 2 SP - 466-474 SN - 1435-0661 ER - TY - JOUR TI - A comparison of coffee floral traits under two different agricultural practices AU - Prado, Sara Guiti AU - Collazo, Jaime A. AU - Stevenson, Philip C. AU - Irwin, Rebecca E. T2 - SCIENTIFIC REPORTS AB - Abstract Floral traits and rewards are important in mediating interactions between plants and pollinators. Agricultural management practices can affect abiotic factors known to influence floral traits; however, our understanding of the links between agricultural practices and floral trait expression is still poorly understood. Variation in floral morphological, nectar, and pollen traits of two important agricultural species, Coffea arabica and C. canephora , was assessed under different agricultural practices (sun and shade). Corolla diameter and corolla tube length were larger and pollen total nitrogen content greater in shade plantations of C. canephora than sun plantations. Corolla tube length and anther filament length were larger in shade plantations of C. arabica . No effect of agricultural practice was found on nectar volume, sugar or caffeine concentrations, or pollen production. Pollen total nitrogen content was lower in sun than shade plantations of C. canephora , but no difference was found between sun and shade for C. arabica . This study provides baseline data on the influence of agronomic practices on C. arabica and C. canephora floral traits and also helps fill a gap in knowledge about the effects of shade trees on floral traits, which can be pertinent to other agroforestry systems. DA - 2019/5/14/ PY - 2019/5/14/ DO - 10.1038/s41598-019-43753-y VL - 9 SP - SN - 2045-2322 ER - TY - JOUR TI - Diel fluctuations of high level nitrate and dissolved organic carbon concentrations in constructed wetland mesocosms AU - Messer, Tiffany L. AU - Birgand, François AU - Burchell, Michael R. T2 - Ecological Engineering AB - Portable in situ ultraviolet-visual spectrometers, through high frequency water quality measurements, provide new insight into biogeochemical processes occurring within dynamic ecosystems. Nitrogen and carbon cycling were observed in two distinct wetland mesocosm environments during a two-year mesocosm study. Simulated drainage water was loaded into the mesocosms across seasons with target nitrate-N levels between 2.5 and 10 mg L−1. Nitrate-N and dissolved organic carbon concentrations in the water column were measured hourly with the spectrometer and calibrated with water quality grab samples. Prominent and unique diel cycles were observed in both nitrate-N and dissolved organic carbon readings from the spectrometer, which reveal biogeochemical processes in these systems are more complicated than typically considered in empirical models. Findings support the importance of utilizing high frequency monitoring to advance current knowledge of nitrogen and carbon processes occurring in treatment wetland ecosystems. DA - 2019/8// PY - 2019/8// DO - 10.1016/j.ecoleng.2019.04.027 VL - 133 SP - 76-87 J2 - Ecological Engineering LA - en OP - SN - 0925-8574 UR - http://dx.doi.org/10.1016/j.ecoleng.2019.04.027 DB - Crossref KW - Wetlands KW - Dissolved organic carbon KW - Nitrate-N KW - Biogeochemistry KW - Diel cycling ER - TY - JOUR TI - Field Evidence of a Natural Capillary Barrier in a Gravel Alluvial Aquifer AU - Halihan, Todd AU - Miller, Ronald B. AU - Correll, David AU - Heeren, Derek M. AU - Fox, Garey A. T2 - Vadose Zone Journal AB - Core Ideas A tracer test in a gravel aquifer detected a natural capillary barrier. Electrical resistivity data combined with well data found two separate vadose zone flow paths. Phosphorus transport is limited, as it needs to migrate through soil before gravel. Ozark streams commonly feature “composite” floodplains, in which the vadose zone consists of silt or silt loam soils (∼1 m thick) overlying gravel subsoil. Previous work has shown that preferential flow paths can exist within the gravel subsoil, which can conduct water and P at rates exceeding the sorption capacity of the gravel. At a site on Barren Fork Creek, a 1‐ by 1‐m infiltration plot was constructed and an infiltration experiment was performed using sequentially introduced solutes including P (the constituent of regulatory interest), Rhodamine‐WT (Rh‐WT, a visual tracer), and Cl − (an electrical tracer). The solute transport was measured with monitoring wells (MWs) placed 1 m from the plot boundary and 5 m down the groundwater flow gradient using an electrical resistivity imaging (ERI) array. The ERI method utilized differences between a pre‐infiltration background image and subsequent temporal images taken during the test to quantify changes induced by the tracers. The infiltration test maintained a steady‐state flow rate of 4.5 L min −1 for 84.75 h. Electrical resistivity imaging data showed significant changes in resistivity induced by the tracers within the soil vadose zone under the plot but no similar changes within the gravel, indicating that the interface was acting as a capillary barrier. Electrical resistivity images 5 m away from the plot showed tracer breakthrough into the gravel in areas not sampled by the MWs. Solute detection was limited in MWs, indicating that MWs could not adequately monitor movement below the capillary barrier because it controlled migration of solute to the heterogeneous phreatic zone. DA - 2019/// PY - 2019/// DO - 10.2136/vzj2018.01.0008 VL - 18 IS - 1 SP - 180008 J2 - Vadose Zone Journal LA - en OP - SN - 1539-1663 UR - http://dx.doi.org/10.2136/vzj2018.01.0008 DB - Crossref ER - TY - JOUR TI - Risk Assessment and Recommendations for Forester Exposure to Hymenoptera AU - Dillane, Danielle AU - Richards, Stephanie L. AU - Balanay, Jo Anne G. AU - Langley, Ricky T2 - JOURNAL OF AGROMEDICINE AB - Objective: Ants, bees, hornets, wasps, and yellow jackets (insects in Order Hymenoptera) are potentially a serious concern to outdoor workers, as the venom from their stings can cause life-threatening allergic reactions. This study assessed the impacts of Hymenoptera stings and related worker training regimes of forestry workers across the United States (US).Methods: A survey was distributed to nearly 2,000 outdoor workers in the forestry industry from four US regions (South, West, Northeast, and Midwest).Results: Ants are a primary concern in the South, with >75% of participants reporting ant stings within the last 5 years. Bees, hornets, wasps, and yellow jackets are a concern for surveyed foresters in all US regions, with 60–70% and 75–93% of participants, respectively, having been stung by bees or hornets/wasps/yellow jackets within the last 5 years. Despite such a large number of participants experiencing stings, nearly 75% of participants were not concerned about being stung or their reaction to stings. Approximately, 70% of participants reported not having received any safety training related to Hymenoptera from their employers.Conclusion: No significant difference was shown in the number of foresters stung at work between safety trained and non-safety trained participants. However, it was significantly more likely for participants to carry a first aid kit if they had received Hymenoptera safety training. Consequently, more comprehensive and frequent training should be considered to help reduce risk of exposure to Hymenoptera. DA - 2019/4/3/ PY - 2019/4/3/ DO - 10.1080/1059924X.2019.1567425 VL - 24 IS - 2 SP - 146-156 SN - 1545-0813 KW - Sting KW - injury KW - occupational health KW - outdoor worker KW - forester ER - TY - JOUR TI - The Development of the INFEWS-ER: A Virtual Resource Center for Transdisciplinary Graduate Student Training at the Nexus of Food, Energy, and Water AU - Rodríguez, Luis F. AU - Marshall, Anna-Maria AU - Cotton, Dan AU - Koelsch, Richard AU - Koziel, Jacek AU - Meyer, Deanne AU - Steward, Dan AU - Heemstra, Jill AU - Padmanabahn, Anand AU - Classen, John AU - Meyer, Nathan J. AU - Ruddell, Benjamin L. AU - Ryan, Sean M. AU - Cai, Ximing AU - Habib, Emad AU - Saundry, Peter D. T2 - Frontiers in Environmental Science AB - Problems at the nexus of Food, Energy and Water Systems (FEWS) are among the most complex challenges we face. Spanning simple to complex temporal, geographic, social, and political framings, the questions raised at this nexus require multi-disciplinary if not transdisciplinary approaches. Answers to these questions must draw from engineering, the physical and biological sciences, and the social sciences. Practical solutions depend upon a wide community of stakeholders, including industry, policy-makers, and the general public. Yet there are many obstacles to working in a transdisciplinary environment: unfamiliar concepts, specialized terminology, and countless 'blind' spots. Graduate education occurs in disciplinary 'silos', often with little regard for the unintended consequences of our research. Existing pedagogical models do not usually train students to understand neighboring disciplines, thus limiting student learning to narrow areas of expertise, and obstructing their potential for transdisciplinary discourse over their careers. Our goal is a virtual resource center—the INFEWS-ER—that provides educational opportunities to supplement graduate students, especially in their development of transdisciplinary competences. Addressing the grand challenges at the heart of the FEWS nexus will depend upon such competence. Students and scholars from diverse disciplines are working together to develop the INFEWS-ER. To date, we have sponsored both a workshop and a symposium to identify priorities to design the initial curriculum. We have also conducted surveys of the larger community of FEWS researchers. Our work confirms a widespread interest in transdisciplinary training and helps to identify core themes and promising pedagogical approaches. Our curriculum now centers upon several 'Cohort Challenges', supported by various 'Toolbox Modules' organized around key themes (e.g., communicating science). We plan to initiate the first cohort of students in October of 2018. Students who successfully complete their Cohort Challenges will be certified as the FEW Graduate Scholars. In this paper, we describe the development of this curriculum. We begin with the need for training in transdisciplinary research. We then describe the workshop and symposium, as well as our survey results. We conclude with an outline of the curriculum, including the current Cohort Challenges and Toolbox Modules. DA - 2019/4/25/ PY - 2019/4/25/ DO - 10.3389/fenvs.2019.00038 VL - 7 SP - J2 - Front. Environ. Sci. OP - SN - 2296-665X UR - http://dx.doi.org/10.3389/fenvs.2019.00038 DB - Crossref KW - collaborative learning KW - pedagogy KW - convergence research KW - divergent thinking KW - team-based learning KW - online education KW - active learning KW - wicked problems ER - TY - JOUR TI - A maize cytochrome b-c1 complex subunit protein ZmQCR7 controls variation in the hypersensitive response AU - He, Yijian AU - Kim, Saet-Byul AU - Balint-Kurti, Peter T2 - PLANTA DA - 2019/5// PY - 2019/5// DO - 10.1007/s00425-019-03092-8 VL - 249 IS - 5 SP - 1477-1485 SN - 1432-2048 UR - https://doi.org/10.1007/s00425-019-03092-8 KW - Hypersensitive response KW - Maize KW - Mitochondrial electron transport chain KW - Reactive oxygen species KW - Resistance genes ER - TY - JOUR TI - Optimization of antioxidant extraction from edible brown algae Ascophyllum nodosum using response surface methodology AU - Liu, Xin AU - Luo, Guanghong AU - Wang, Lijuan AU - Yuan, Wenqiao T2 - FOOD AND BIOPRODUCTS PROCESSING AB - Brown algae are valuable sources of health-benefiting compounds, such as polyphenols, proteins, and polysaccharides. In the present study, a binary solvent system of ethanol and water was used to obtain crude extracts from edible brown algae Ascophyllum nodosum. The extraction process was optimized using Box–Behnken design and response surface methodology to obtain crude extracts with strong antioxidant activity and high yield. Three variables including solvent-to-solid ratio (30–70 ml/g), ethanol concentration in the solvent system (40–80%), and extraction temperature (20–60 °C) were investigated to optimize the extraction process. The condition for maximum antioxidant activity of the crude extract was found at 70 ml/g solvent-to-solid ratio, 80% ethanol concentration, and 20 °C extraction temperature, while the condition for the highest crude extract yield was 40 ml/g solvent–solid-ratio, 44.83% ethanol concentration and 60 °C extraction temperature. Under the model-predicted optimal conditions, the predicted antioxidant activity and yield of the crude extract were 74.01 ml/g (1/IC50) and 55.60 mg extract/g-algae, which were in close agreement with the experimental results of 74.05 ml/g and 53.80 mg extract/g-algae, respectively, suggesting that the models could accurately predict and improve the extraction of antioxidants from A. nodosum. DA - 2019/3// PY - 2019/3// DO - 10.1016/j.fbp.2019.01.003 VL - 114 SP - 205-215 SN - 1744-3571 KW - Antioxidant KW - Brown algae KW - Polyphenol KW - Phlorotannin KW - RSM KW - Ascophyllum nodosum ER - TY - JOUR TI - Featured Collection Introduction: The Emerging Science of Aquatic System Connectivity I AU - Jones, C. Nathan AU - Nelson, Natalie G. AU - Smith, Lora L. T2 - JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AB - Abstract The growing aquatic system science community includes interdisciplinary researchers collectively working to improve the physical, chemical, and biological functions of aquatic systems. Connectivity describes the flow of materials, organisms, and energy between ecosystems or ecosystem components, and it serves as a unifying concept for the study, management, and restoration of aquatic systems. This featured collection was motivated by the American Water Resources Association (AWRA) Specialty Conference, Connecting the Dots: The Emerging Science of Aquatic System Connectivity . Held in May 2017 in Snowbird, Utah, the conference consisted of 33 technical sessions with over 140 presenters from across engineering, earth science, and life science disciplines. Session topics ranged from basic and applied research, to management applications and policy discussions. This collection, the first in a series of two, contains 11 manuscripts and builds upon the momentum of the AWRA specialty conference by facilitating continued conversations about aquatic systems connectivity and providing guidance for future interdisciplinary research. DA - 2019/4// PY - 2019/4// DO - 10.1111/1752-1688.12739 VL - 55 IS - 2 SP - 287-293 SN - 1752-1688 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85063958321&partnerID=MN8TOARS KW - aquatic system connectivity KW - hydrologic connectivity KW - ecosystem functions KW - ecosystem services ER - TY - JOUR TI - Effect of controlled drainage on nitrogen fate and transport for a subsurface drained grass field receiving liquid swine lagoon effluent AU - Liu, Yu AU - Youssef, Mohamed A. AU - Chescheir, George M. AU - Appelboom, Timothy W. AU - Poole, Chad A. AU - Arellano, Consuelo AU - Skaggs, R. Wayne T2 - AGRICULTURAL WATER MANAGEMENT AB - Application of livestock manure has become a principal nutrient source in groundwater and surface water. The goal of this research was to investigate the effect of controlled drainage (CD) on nitrogen (N) fate and transport for a subsurface drained grass field receiving liquid swine lagoon effluent (SLE). A four-year field experiment was conducted on a naturally poorly drained pasture in eastern North Carolina. The 1.25 ha experimental field was artificially drained by subsurface drains installed at 1.0 m depth and 12.5 m spacing. Two treatments, replicated twice were implemented: conventional drainage (FD) and CD. The CD management protocol was more intensive compared to previous studies. The drain outlets of CD plot were set at 36 cm below soil surface all year round except several days before irrigation application when water table depth was shallower than 65 cm below surface. Controlled drainage significantly reduced drainage flow and TN loading via subsurface drain lines by an average of 397 mm yr−1 (93%) and 34.5 kg N ha−1 yr−1 (94%), respectively. DRAINMOD hydrologic simulations indicated that 96% of the reduction in predicted drain flow was attributed to increased lateral seepage. The nitrogen that did not drain from the field in response to CD was lost via enhanced denitrification (67%) and lateral seepage to adjacent fields (33%). This study clearly demonstrated how CD management affects the N fate and transport through seepage and denitrification process. DA - 2019/5/20/ PY - 2019/5/20/ DO - 10.1016/j.agwat.2019.02.018 VL - 217 SP - 440-451 SN - 1873-2283 KW - Controlled drainage KW - Swine lagoon effluent KW - Drainage water quality KW - Nitrogen KW - Denitrification KW - Lateral seepage ER - TY - JOUR TI - Spatial and Temporal Variations of PM2.5 in North Carolina AU - Cheng, Bin AU - Wang-Li, Lingjuan T2 - AEROSOL AND AIR QUALITY RESEARCH AB - Studies have indicated that the adverse effects on human health and the decrease in visibility caused by fine particulate matter (PM2.5) exhibit spatial heterogeneity. Moreover, the environmental effects produced by different chemical compositions of PM2.5 vary on a regional scale. Therefore, understanding the spatiotemporal variations and chemical compositions of PM2.5 is necessary for assessing the regional impacts. Secondary inorganic PM2.5 (iPM2.5) is formed through chemical reactions between the base gas NH3 and acidic gas pollutants (e.g., NO2 or SO2). The major components of iPM2.5 include NH4+, SO42–, and NO3–. To fully comprehend the regional impacts of PM2.5, this research quantifies the spatiotemporal variations of iPM2.5 with the aim of evaluating the contributions from iPM2.5 to PM2.5 in North Carolina (NC). The concentrations (at 34 sites) and chemical components (at 7 sites) of PM2.5 from 2005 to 2014 were extracted from the EPA’s AirData, with the highest concentrations measured in the urban areas of central NC. Notably, PM2.5 concentrations have been significantly reduced over the past 10 years, with a concurrent decreasing trend in iPM2.5. Seasonal variation analysis indicates that PM2.5 concentrations were higher in summer and lower in winter; however, significant variation occurred only between 2005 and 2011. Although iPM2.5 formed the largest mass fraction of PM2.5 for 2005–2011, organic carbon matter (OCM) contributed the dominant share for 2012–2014. Significant seasonal variations in the iPM2.5 mass fractions were also observed, with NO3– and SO42– exhibiting inverse variations. This study links the ambient PM2.5 to various sources by revealing the spatiotemporal variations of PM2.5 and their associated chemical compositions in NC, thereby enabling the development of effective control and mitigation strategies. DA - 2019/4// PY - 2019/4// DO - 10.4209/aaqr.2018.03.0111 VL - 19 IS - 4 SP - 698-710 SN - 2071-1409 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85065388819&partnerID=MN8TOARS KW - Chemical compositions KW - Inorganic PM2.5 KW - Spatiotemporal variations ER - TY - JOUR TI - A Retrospective Comparison of Water Quality Treatment in a Bioretention Cell 16 Years Following Initial Analysis AU - Johnson, Jeffrey AU - Hunt, William T2 - Sustainability AB - One of the most popular stormwater practices in (sub-)urban North Carolina is bioretention. While bioretention has been researched intensively to determine the most efficient designs, few long-term studies have attempted to assess the performance of older bioretention. However, previous research and design guidance for bioretention has predicted long-term water quality treatment. This study compared discharged concentrations and loads of nitrogen and phosphorus from a bioretention cell (1) post-construction and (2) following 17 years of treatment. A conventionally-drained bioretention cell with lateral underdrains in Chapel Hill, North Carolina, USA, was first monitored post-construction for 10-months from 2002–2003 and, again following continuous use, for 14 months from 2017–2018. Estimated mass load reductions during the initial monitoring period were 40% for total nitrogen (TN) and 65% for total phosphorus (TP). Mass load reductions were increased 17 years after construction, with reductions of 72% and 79% for TN and TP, respectively. Plant growth, death, and decay over the 17-year life of the bioretention cell are hypothesized to have contributed additional nitrogen assimilation and carbon to the fill media, serving as a catalyst for nitrogen treatment. Phosphorus removal remained relatively unchanged between the two monitoring periods. Filter media samples indicated the top 20 cm of filter media were nearing phosphorus saturation, but with 1.2 m of filter media, lower depths would most likely continue to provide treatment. If designed, built, and maintained correctly, bioretention appears to provide sustained treatment of stormwater runoff for nitrogen and phosphorus for nearly two decades, and likely longer. DA - 2019/4/2/ PY - 2019/4/2/ DO - 10.3390/su11071945 VL - 11 IS - 7 SP - 1945 UR - https://www.mdpi.com/2071-1050/11/7/1945 KW - stormwater management KW - green infrastructure KW - bioretention KW - biofilter KW - sustainable drainage systems KW - water quality KW - low impact development KW - nitrogen KW - phosphorus ER - TY - JOUR TI - Development of PLEAD: A Database Containing Event-based Runoff Phosphorus Loadings from Agricultural Fields AU - Bolster, Carl H. AU - Baffaut, Claire AU - Nelson, Nathan O. AU - Osmond, Deanna L. AU - Cabrera, Miguel L. AU - Ramirez-Avila, John J. AU - Sharpley, Andrew N. AU - Veith, Tamie L. AU - McFarland, Anne M. S. AU - Senaviratne, Anomaa G. M. M. M. AU - Pierzynski, Gary M. AU - Udawatta, Ranjith P. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Computer models are commonly used for predicting risks of runoff P loss from agricultural fields by enabling simulation of various management practices and climatic scenarios. For P loss models to be useful tools, however, they must accurately predict P loss for a wide range of climatic, physiographic, and land management conditions. A complicating factor in developing and evaluating P loss models is the relative scarcity of available measured field data that adequately capture P losses before and after implementing management practices in a variety of physiographic settings. Here, we describe the development of the P Loss in runoff Events from Agricultural fields Database (PLEAD)—a compilation of event‐based, field‐scale dissolved and/or total P loss runoff loadings from agricultural fields collected at various research sites located in the US Heartland and southern United States. The database also includes runoff and erosion rates; soil‐test P; tillage practices; planting and harvesting rates and practices; fertilizer application rate, method, and timing; manure application rate, method, and timing; and livestock grazing density and timing. In total, >1800 individual runoff events—ranging in duration from 0.4 to 97 h—have been included in the database. Event runoff P losses ranged from <0.05 to 1.3 and 3.0 kg P ha −1 for dissolved and total P, respectively. The data contained in this database have been used in multiple research studies to address important modeling questions relevant to P management planning. We provide these data to encourage additional studies by other researchers. The PLEAD database is available at https://doi.org/10.15482/USDA.ADC/1482380 . Core Ideas Development of database containing P loss from agricultural fields is described. We provide public access to P loss data for individual runoff events. The data can be used to evaluate P loss models and P Indices. DA - 2019/// PY - 2019/// DO - 10.2134/jeq2018.09.0337 VL - 48 IS - 2 SP - 510-517 SN - 1537-2537 ER - TY - JOUR TI - Diverse Components of Resistance to Fusarium verticillioides Infection and Fumonisin Contamination in Four Maize Recombinant Inbred Families AU - Morales, Laura AU - Zila, Charles T. AU - Mejia, Danilo E. Moreta AU - Arbelaez, Melissa Montoya AU - Balint-Kurti, Peter J. AU - Holland, James B. AU - Nelson, Rebecca J. T2 - TOXINS AB - The fungus Fusarium verticillioides can infect maize ears, causing Fusarium ear rot (FER) and contaminating the grain with fumonisins (FUM), which are harmful to humans and animals. Breeding for resistance to FER and FUM and post-harvest sorting of grain are two strategies for reducing FUM in the food system. Kernel and cob tissues have been previously associated with differential FER and FUM. Four recombinant inbred line families from the maize nested associated mapping population were grown and inoculated with F. verticillioides across four environments, and we evaluated the kernels for external and internal infection severity as well as FUM contamination. We also employed publicly available phenotypes on innate ear morphology to explore genetic relationships between ear architecture and resistance to FER and FUM. The four families revealed wide variation in external symptomatology at the phenotypic level. Kernel bulk density under inoculation was an accurate indicator of FUM levels. Genotypes with lower kernel density-under both inoculated and uninoculated conditions-and larger cobs were more susceptible to infection and FUM contamination. Quantitative trait locus (QTL) intervals could be classified as putatively resistance-specific and putatively shared for ear and resistance traits. Both types of QTL mapped in this study had substantial overlap with previously reported loci for resistance to FER and FUM. Ear morphology may be a component of resistance to F. verticillioides infection and FUM accumulation. DA - 2019/2// PY - 2019/2// DO - 10.3390/toxins11020086 VL - 11 IS - 2 SP - SN - 2072-6651 UR - http://www.mdpi.com/2072-6651/11/2/86 KW - maize KW - mycotoxins KW - fumonisin KW - disease resistance KW - morphology ER - TY - JOUR TI - The effect of salinity and alkalinity on growth and the accumulation of copper and zinc in the Chlorophyta Ulva fasciata AU - Geddie, Alexander W. AU - Hall, Steven G. T2 - ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY AB - Copper and zinc accumulation in macroalgae is a complex issue. While these metals exist as micronutrients and can serve to add nutritional value to the macroalgae when consumed by both plants and animals, elevated levels of the metals can reduce growth or even kill the algae. Many water parameters can influence the toxicity of the metals, though past studies have rarely isolated individual water parameters. This study aimed to independently determine the effects that salinity and alkalinity have on the growth and accumulation of these two metals on the macroalgae Ulva fasciata, distinguishing the effects of salinity and alkalinity as whole parameters from the collective effects of the water different constituents. The effect of salinity was determined using sodium chloride additions rather than seawater dilution, as performed in past studies, while alkalinity was tested using sodium bicarbonate additions to artificial seawater. The results of the study reinforce previous findings that copper is very toxic to macroalgae, even at low concentrations (50 µg L−1) though the effects of zinc remain inconclusive at 50 µg L−1, since the experiment was conducted over only a two-week trial period. The research suggests that salinity and alkalinity have no significant effect on the toxicity of copper to the growth of the macroalgae, but alkalinity significantly reduced copper and increased zinc accumulation in U. fasciata. The results of this study warrant further research in the field to investigate which other components of seawater and macroalgae reduce metal toxicity in the macroalgae. Additionally, these findings suggest the need for further refinement of toxicity models when adapted to macroalgae. DA - 2019/5/15/ PY - 2019/5/15/ DO - 10.1016/j.ecoenv.2019.01.088 VL - 172 SP - 203-209 SN - 1090-2414 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85060724969&partnerID=MN8TOARS KW - Ulva KW - Copper KW - Zinc KW - Bioaccumulation KW - Salinity KW - Alkalinity ER - TY - JOUR TI - The co-existence of anammox genera in an expanded granular sludge bed reactor with biomass carriers for nitrogen removal AU - Wu, Yang AU - Wang, Yuexing AU - De Costa, Yashika G. AU - Tong, Zhida AU - Cheng, Jay J. AU - Zhou, Lijie AU - Zhuang, Wei-Qin AU - Yu, Ke T2 - APPLIED MICROBIOLOGY AND BIOTECHNOLOGY DA - 2019/2// PY - 2019/2// DO - 10.1007/s00253-018-9494-3 VL - 103 IS - 3 SP - 1231-1242 SN - 1432-0614 KW - Anammox KW - EGSB KW - Nitrogen removal KW - Biomass carriers KW - Microbial communities ER - TY - JOUR TI - Laboratory Experiments on the Removal of Soil Plugs During Soil Piping and Internal Erosion AU - Wanger, Mikayla AU - Wanger, Mikayla AU - Fox, Garey A. AU - Wilson, Glenn V. AU - Nieber, John AU - Fox, Garey A. AU - Wilson, Glenn V. AU - Nieber, John T2 - Transactions of the ASABE AB - Abstract. Plugging of soil pipes can be detrimental to hillslope stability. A soil pipe commonly becomes plugged through internal erosion when the pipe wall collapses. When a pipe becomes plugged, a pressure buildup occurs upslope from the plug. This pressure may be enough to remove the plug, or the pressure may continue to build in the soil matrix, which may lead to hillslope failures. Based on field observations, it is known that both processes occur, but limited data exist to understand if and when plug removal or pressure buildup occurs or how to model these processes. This study involved well-controlled laboratory experiments to determine instantaneous pressure buildup behind soil plugs and conditions for which an idealized plug in a soil pipe will be removed. Laboratory experiments were conducted with a smooth or roughened 100 cm long clear polyvinyl chloride (PVC) pipe. A pipe plug (3 or 6 cm) was established 90 cm along the pipe length. Triplicate experiments were conducted with two pipe diameters, two soil types (sand and sandy loam), two plug lengths, three pipe roughness values, various packing densities, and with both dynamic and constant pressure heads. Digital pressure gauges were installed to monitor pressures in the pipe both before and after the plug. The upslope pressure and the length of time that the plug withstood the pressure before removal were recorded. Regardless of pressurized time, all plugs were initially mobilized as intact plugs and then in many cases quickly disaggregated. Some sandy loam plugs withstood pressures of 100 cm; more cohesive plugs could withstand much higher pressures. In addition, pressurized times exceeded 1000 s for some plug conditions even with short (3 to 6 cm) plugs. Therefore, hillslopes upslope of a plugged soil pipe may experience considerable pressure buildup for extended periods of time. Plug physical characteristics are important; for example, the plug’s bulk density had a positive exponential relationship with the pressurized time. Soil water dynamics inside the plug will need to be considered, as well as the hydraulic boundary providing inflow to the soil pipe. These experiments provided insight into the dynamics of plugged soil pipes with the eventual goal of assisting in being able to better predict internal erosion and hillslope failure. Future experiments are needed across a wider range of soil types. Keywords: Hillslope, Internal erosion, Macropore, Pipe clogging, Pipeflow, Pressure buildup, Sediment transport, Soil plug. DA - 2019/// PY - 2019/// DO - 10.13031/trans.13092 VL - 62 IS - 1 SP - 83-93 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/trans.13092 DB - Crossref KW - Hillslope KW - Internal erosion KW - Macropore KW - Pipe clogging KW - Pipeflow KW - Pressure buildup KW - Sediment transport KW - Soil plug ER - TY - JOUR TI - Impacts on soil nitrogen availability of converting managed pine plantation into switchgrass monoculture for bioenergy AU - Cacho, Julian F. AU - Youssef, Mohamed A. AU - Shi, Wei AU - Chescheir, George M. AU - Skaggs, R. Wayne AU - Tian, Shiying AU - Leggett, Zakiya H. AU - Sucre, Eric B. AU - Nettles, Jami E. AU - Arellano, Consuelo T2 - SCIENCE OF THE TOTAL ENVIRONMENT AB - Biofuels derived from lignocellulosic materials is one of the options in addressing issues on climate change and energy independence. One of the most promising bioenergy crops is switchgrass (Panicum virgatum L.), particularly in North America. Future advancement in large-scale conversion of lignocellulosic feedstocks and relatively more competitive price for biomass and other economic advantages could lead to landowners opting to venture on switchgrass monoculture (SWITCH) in lieu of loblolly pine monoculture (PINE). Therefore, we investigated the conversion of previously managed loblolly pine stand into SWITCH in eastern North Carolina, U.S.A. on soil N availability. Treatments included PINE, SWTICH, and mature loblolly pine stand (REF). Each treatment was replicated three times on 0.8 ha plots drained by open ditches dug 1.0–1.2 m deep and spaced at 100 m. Rates of net N mineralization (Nm) and nitrification (Nn) at the top 20 cm were measured using sequential in-situ techniques in 2011 and 2012 (the 3rd and 4th years of establishment, respectively) along with a one-time laboratory incubation. On average, PINE, SWITCH, and REF can have field net Nm rates up to 0.40, 0.34 and 0.44 mg N·kg soil−1·d−1, respectively, and net Nn rates up to 0.14, 0.08 and 0.10 mg N·kg soil−1·d−1, respectively. Annually, net Nm rates ranged from 136.98 to 167.21, 62.00 to 142.61, and 63.57 to 127.95 kg N·ha−1, and net Nn rates were 56.31–62.98, 16.45–30.45, 31.99–32.94 kg N·ha−1 in PINE, SWITCH, and REF, respectively. Treatment effect was not significant on field Nm rate (p = 0.091). However, SWITCH significantly reduced nitrate-N production (p < 0.01). Overall, results indicated that establishment of SWITCH on poorly drained lands previously under PINE is less likely to significantly impact total soil N availability and potentially has minimum N leaching losses since soil mineral N under this system will be dominated by ammonium-N. DA - 2019/3/1/ PY - 2019/3/1/ DO - 10.1016/j.scitotenv.2018.11.133 VL - 654 SP - 1326-1336 SN - 1879-1026 KW - Managed forests KW - Switchgrass KW - Biomass KW - Biofuel KW - Soil N cycling KW - Soil N dynamics ER - TY - JOUR TI - An introduction to copper and zinc pollution in macroalgae: for use in remediation and nutritional applications AU - Geddie, Alexander W. AU - Hall, Steven G. T2 - JOURNAL OF APPLIED PHYCOLOGY DA - 2019/2// PY - 2019/2// DO - 10.1007/s10811-018-1580-5 VL - 31 IS - 1 SP - 691-708 SN - 1573-5176 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85050529157&partnerID=MN8TOARS KW - Macroalgae KW - Copper KW - Zinc KW - Aquatic pollution ER - TY - JOUR TI - Controls on mineral-associated organic matter formation in a degraded Oxisol AU - Ye, Chenglong AU - Hall, Steven J. AU - Hu, Shuijin T2 - GEODERMA AB - 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. DA - 2019/3/15/ PY - 2019/3/15/ DO - 10.1016/j.geoderma.2018.12.011 VL - 338 SP - 383-392 SN - 1872-6259 KW - Birch effect KW - Drying rewetting KW - Oxygen fluctuations KW - Litter decomposition KW - Iron redox KW - Mineral-organic associations ER - TY - JOUR TI - Using Maize Chromosome Segment Substitution Line Populations for the Identification of Loci Associated with Multiple Disease Resistance AU - Lopez-Zuniga, Luis O AU - Wolters, Petra AU - Davis, Scott AU - Weldekidan, Teclemariam AU - Kolkman, Judith M AU - Nelson, Rebecca AU - Hooda, K S AU - Rucker, Elizabeth AU - Thomason, Wade AU - Wisser, Randall AU - Balint-Kurti, Peter T2 - G3 Genes|Genomes|Genetics AB - Abstract Southern Leaf Blight (SLB), Northern Leaf Blight (NLB), and Gray Leaf Spot (GLS) caused by Cochliobolus heterostrophus, Setosphaeria turcica, and Cercospora zeae-maydis respectively, are among the most important diseases of corn worldwide. Previously, moderately high and significantly positive genetic correlations between resistance levels to each of these diseases were identified in a panel of 253 diverse maize inbred lines. The goal of this study was to identify loci underlying disease resistance in some of the most multiple disease resistant (MDR) lines by the creation of chromosome segment substitution line (CSSL) populations in multiple disease susceptible (MDS) backgrounds. Four MDR lines (NC304, NC344, Ki3, NC262) were used as donor parents and two MDS lines (Oh7B, H100) were used as recurrent parents to produce eight BC3F4:5 CSSL populations comprising 1,611 lines in total. Each population was genotyped and assessed for each disease in replicated trials in two environments. Moderate to high heritabilities on an entry mean basis were observed (0.32 to 0.83). Several lines in each population were significantly more resistant than the MDS parental lines for each disease. Multiple quantitative trait loci (QTL) for disease resistance were detected for each disease in most of the populations. Seventeen QTL were associated with variation in resistance to more than one disease (SLB/NLB: 2; SLB/GLS: 7; NLB/GLS: 2 and 6 to all three diseases). For most populations and most disease combinations, significant correlations were observed between disease scores and also between marker effects for each disease. The number of lines that were resistant to more than one disease was significantly higher than would be expected by chance. Using the results from individual QTL analyses, a composite statistic based on Mahalanobis distance (Md) was used to identify joint marker associations with multiple diseases. Across all populations and diseases, 246 markers had significant Md values. However further analysis revealed that most of these associations were due to strong QTL effects on a single disease. Together, these findings reinforce our previous conclusions that loci associated with resistance to different diseases are clustered in the genome more often than would be expected by chance. Nevertheless true MDR loci which have significant effects on more than one disease are still much rarer than loci with single disease effects. DA - 2019/1/1/ PY - 2019/1/1/ DO - 10.1534/g3.118.200866 VL - 9 IS - 1 SP - 189-201 LA - en OP - SN - 2160-1836 UR - http://dx.doi.org/10.1534/g3.118.200866 DB - Crossref KW - Maize disease resistance KW - Multiple disease resistance KW - QTL ER - TY - JOUR TI - Carbon storage potential in a recently created brackish marsh in eastern North Carolina, USA AU - Shiau, Yo-Jin AU - Burchell, Michael R. AU - Krauss, Ken W. AU - Broome, Stephen W. AU - Birgand, Francois T2 - Ecological Engineering AB - Carbon (C) sequestration through accumulated plant biomass and storage in soils can potentially make wetland ecosystems net C sinks. Here, we collected GHG flux, plant biomass, and litter decomposition data from three distinct vegetation zones (Spartina alterniflora, Juncus roemerianus and Spartina patens) on a 7-year-old created brackish marsh in North Carolina, USA, and integrate these data into an overall C mass balance budget. The marsh fixed an average of 1.85 g C m−2 day−1 through plant photosynthesis. About 41–46% of the fixed C remained in plants, while 18.4% of the C was decomposed and released back to the atmosphere as CO2 and CH4, and 8.6–13.2% of the decomposed C was stored as soil C. In all, this created marsh sequestered 28.7–44.7 Mg CO2 year−1 across the 14 ha marsh. Because the brackish marsh emitted only small amounts of CH4 and N2O, the CO2 equivalent emission of the marsh was −0.87 to −0.56 g CO2-eq m−2 day−1, indicating the marsh has a net effect in reducing GHGs to the atmosphere and contributes to cooling. However, resultant CO2 credit (through the increment of soil C) would be worth only $30.76–$47.90 USD per hectare annually, or $431–$671 per year for the project, which, coupled with other enhanced ecosystem services, could provide landowners with some additional economic incentive for future creation projects. Nevertheless, C mass balance determinations and radiative cooling metrics showed promise in demonstrating the potential of a young created brackish marsh to act as a net carbon sink. DA - 2019/2// PY - 2019/2// DO - 10.1016/j.ecoleng.2018.09.007 VL - 127 SP - 579-588 J2 - Ecological Engineering LA - en OP - SN - 0925-8574 UR - http://dx.doi.org/10.1016/j.ecoleng.2018.09.007 DB - Crossref KW - Carbon sequestration KW - Greenhouse gas emissions KW - Brackish marsh creation KW - Ecosystem services ER - TY - JOUR TI - Drying–Rewetting Cycles Affect Nitrate Removal Rates in Woodchip Bioreactors AU - Maxwell, Bryan M. AU - Birgand, François AU - Schipper, Louis A. AU - Christianson, Laura E. AU - Tian, Shiying AU - Helmers, Matthew J. AU - Williams, David J. AU - Chescheir, George M. AU - Youssef, Mohamed A. T2 - Journal of Environment Quality AB - Woodchip bioreactors are widely used to control nitrogen export from agriculture using denitrification. There is abundant evidence that drying-rewetting (DRW) cycles can promote enhanced metabolic rates in soils. A 287-d experiment investigated the effects of weekly DRW cycles on nitrate (NO) removal in woodchip columns in the laboratory receiving constant flow of nitrated water. Columns were exposed to continuous saturation (SAT) or to weekly, 8-h drying-rewetting (8 h of aerobiosis followed by saturation) cycles (DRW). Nitrate concentrations were measured at the column outlets every 2 h using novel multiplexed sampling methods coupled to spectrophotometric analysis. Drying-rewetting columns showed greater export of total and dissolved organic carbon and increased NO removal rates. Nitrate removal rates in DRW columns increased by up to 80%, relative to SAT columns, although DRW removal rates decreased quickly within 3 d after rewetting. Increased NO removal in DRW columns continued even after 39 DRW cycles, with ∼33% higher total NO mass removed over each weekly DRW cycle. Data collected in this experiment provide strong evidence that DRW cycles can dramatically improve NO removal in woodchip bioreactors, with carbon availability being a likely driver of improved efficiency. These results have implications for hydraulic management of woodchip bioreactors and other denitrification practices. DA - 2019/// PY - 2019/// DO - 10.2134/jeq2018.05.0199 VL - 48 IS - 1 SP - 93 LA - en OP - SN - 0047-2425 UR - http://dx.doi.org/10.2134/jeq2018.05.0199 DB - Crossref ER - TY - JOUR TI - Field Monitoring of Downspout Disconnections to Reduce Runoff Volume and Improve Water Quality along the North Carolina Coast AU - Taguchi, Vinicius J. AU - Carey, Erin S. AU - Hunt, William F., III T2 - JOURNAL OF SUSTAINABLE WATER IN THE BUILT ENVIRONMENT AB - Virtually all land development increases stormwater runoff and disrupts the natural hydrologic cycle. This is a particularly important issue for areas developed prior to the widespread application of stormwater control measures (SCMs). Among the simplest and most underused SCMs are downspout disconnections (DSDs), whereby stormwater gutters and downspouts are disconnected from storm sewers, and stormwater is instead routed across a lawn or other pervious surfaces on the property before entering the storm drain. Seven such DSD sites within the Hewletts Creek watershed in Wilmington, North Carolina were monitored for stormwater volume, total suspended solids (TSS), and nutrient reductions over a full hydrologic year. The DSD sites had loading ratios of contributing roof area to infiltrating lawn area ranging from 4:1 to 14:1. Sandy underlying soils within this watershed were expected to improve the effectiveness of these inexpensive SCMs. Significant cumulative volume reductions (α=0.05 level) were found at each site and ranged from 42% to 87%. Significant nitrogen mass reductions (across 4 DSD sites monitored for water quality) ranged from 44% to 90% for the pollutants evaluated; however, none of the sites demonstrated significant reductions in total phosphorus (TP) or orthophosphorus (ortho-P). All TSS mass reductions were significant and ranged from 44% to 88%, with a median value of 75%. It was found that infiltration rates most significantly impacted volume reductions, whereas nutrient mass reductions correlated primarily with infiltration area length. DA - 2019/2// PY - 2019/2// DO - 10.1061/JSWBAY.0000872 VL - 5 IS - 1 SP - SN - 2379-6111 KW - Downspout disconnection KW - Low-impact development KW - Impervious surface KW - Vegetated filter strip KW - Best management practice KW - Stormwater ER -