@article{rudd_neal_genereux_shea_nichols_2023, title={Vulnerability of wells in unconfined and confined aquifers to modern contamination from flood events}, volume={901}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2023.165729}, abstractNote={Groundwater is a primary potable water supply for coastal North Carolina (NC), but the increased intensity of extreme rainfall events and floods may exacerbate surface and subsurface processes that contribute anthropogenic chemicals to wells in the major confined aquifers of this region. We evaluated groundwater for organic chemicals of emerging concern (CEC) and the presence of tritium using flooded and not-flooded wells in the NC Department of Environmental Quality well monitoring network across the NC Coastal Plain. Flooded wells experienced standing water around the well casing at least once during the study period. Tritium concentrations, which indicate modern water presence (water recharged after 1953), were significantly greater in groundwater from flooded wells than not-flooded wells. In confined aquifers, modern water was detected at greater depths in flooded wells (206 m) than not-flooded wells (100 m). Suspect-screening high resolution mass spectrometry (HRMS) analysis of 150 groundwater samples yielded a total of 382 unique organic chemicals. Each groundwater sample contained, on average, 19 tentatively identified chemicals from the NIST 20 mass spectral database (M1) and 9 USEPA ToxCast chemicals. The number of tentatively-identified chemicals per sample was not significantly different among aquifers demonstrating the pervasive presence of the detected CECs in unconfined and confined aquifers. The presence of modern water in groundwater from flooded wells coincided with higher detection frequencies of certain organic contaminant classes, particularly pharmaceuticals, food additives, and regulated aromatic hydrocarbons. These results indicate that wells in both unconfined and confined aquifers are susceptible to modern water contamination during flood events; this finding has critical public health implications for coastal communities.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Rudd, Hayden and Neal, Andy and Genereux, David P. and Shea, Damian and Nichols, Elizabeth Guthrie}, year={2023}, month={Nov} }
 @article{brecht_kong_shea_xia_nichols_2022, title={Non-target and suspect-screening analyses of hydroponic soybeans and passive samplers exposed to different watershed irrigation sources}, volume={826}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2022.153754}, abstractNote={Water scarcity increases the likelihood of irrigating food crops with municipal wastewater that may pose potential dietary risks of regulated and non-regulated organic chemical uptake to edible plant tissues. Only a few studies have used high resolution mass spectrometry (HRMS) to assess the uptake of chemicals of concern into food crops. This study used non-target and suspect-screening analyses to compare total chemical features, tentatively identified chemicals (TICs), and EPA ToxCast chemicals in soybean plants and passive samplers exposed to five different irrigation sources that were collected from an agricultural watershed during mild drought conditions. Secondary-treated municipal wastewater effluent, two surface waters, two ground waters, and deionized municipal tap water were used for two hydroponic experiments: soybean roots and shoots and Composite Integrative Passive Samplers (CIPS) harvested after fourteen days of exposure and soybeans after fifty-six days. CIPS were sealed in separate glass amber jars to evaluate their efficacy to mimic chemical features, TICs, and ToxCast chemical uptake in plant roots, shoots, and beans. Total soybean biomass and water use were greatest for tap water, municipal wastewater, and surface water downstream of the municipal wastewater facility relative to groundwater samples and surface water collected upstream of the wastewater facility. ToxCast chemicals were ubiquitous across watershed irrigation sources in abundance, chemical use category, and number. Wastewater-exposed soybeans had the fewest extractable TICs in plant tissues of all irrigation sources. More ToxCast chemicals were identified in CIPS than extracted from irrigation sources by solid phase extraction. ToxCast chemicals in beans and CIPS were similar in number, chemical use category, and log Kow range. CIPS appear to serve as a useful surrogate for ToxCast chemical uptake in beans, the edible food product.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Brecht, Sarah A. and Kong, Xiang and Shea, Damian and Xia, Xin Rui and Nichols, Elizabeth Guthrie}, year={2022}, month={Jun} }
 @article{neville_emanuel_nichols_vose_2021, title={Extreme Flooding and Nitrogen Dynamics of a Blackwater River}, volume={57}, ISSN={["1944-7973"]}, url={http://dx.doi.org/10.1029/2020wr029106}, DOI={10.1029/2020WR029106}, abstractNote={Abstract}, number={12}, journal={WATER RESOURCES RESEARCH}, publisher={American Geophysical Union (AGU)}, author={Neville, J. A. and Emanuel, R. E. and Nichols, E. G. and Vose, J.}, year={2021}, month={Dec} }
 @article{ghezehei_ewald_hazel_zalesny_nichols_2021, title={Productivity and Profitability of Poplars on Fertile and Marginal Sandy Soils under Different Density and Fertilization Treatments}, volume={12}, ISSN={["1999-4907"]}, url={https://www.mdpi.com/1999-4907/12/7/869}, DOI={10.3390/f12070869}, abstractNote={We evaluated the productivity and profitability of four highly productive poplars including Populus deltoides × P. deltoides (DD ‘140’ and ‘356’), P. deltoides × P. maximowiczii (DM ‘230’), and P. trichocarpa × P. deltoides (TD ‘185’) under two densities (2500 and 5000 trees ha−1), and three fertilization treatments (0, 113, 225 kg nitrogen ha−1) at three sandy coastal sites varying in soil quality. Green stem biomass (GSB) was estimated from the sixth-year stem diameter. Leaf-rust (Melampsora castagne) and beetle damage (by Chrysomela scripta Fabricius), the leaf area index (LAI) and foliar nitrogen, were measured in year two. At all sites, DD and DM had higher survival (>93%) than TD (62–83%). DD produced greater GSB (92.5–219.1 Mg ha−1) than DM (54–60.2 Mg ha−1) and TD (16.5–48.9 Mg ha−1), and this was greater under the higher density (85.9–148.6 Mg ha−1 vs. 55.9–124.9 Mg ha−1). Fertilization significantly increased GSB on fertile soil but not marginal soils; a higher rate did not significantly enhance GSB. Leaf rust was higher for fertile soil (82%) than marginal soils (20–22%), and TD ‘185’ (51% vs. others 34%). C. scripta damage was higher for the higher density (+42%) than lower density, and TD ‘185’ (50% vs. others >38%). LAI was higher on fertile soil (1.85 m2 m−2) than marginal soils (1.35–1.64 m2 m−2), and under the lower density (1.67 m2 m−2 vs. 1.56 m2 m−2). The high GSB producer DD ‘356’ had the lowest LAI (1.39 m2 m−2 vs. 1.80 m2 m−2). Foliar nitrogen varied among genomic groups (DD ‘140’ 1.95%; TD ‘185’ 1.80%). Our plots were unprofitable at a 27 USD Mg−1 delivered price; the biggest profitability barriers were the high costs of higher density establishment and weed control. The best-case treatment combinations of DD (‘140’, ‘356’) would be cost-effective if the price increased by 50% (USD 37.54 Mg−1) or rotations were 12 years (fertile-soil) and longer (marginal soils). The requirement for cost-effectiveness of poplars includes stringent and site-specific weed control which are more important than fertilizer applications.}, number={7}, journal={FORESTS}, author={Ghezehei, Solomon B. and Ewald, Alexander L. and Hazel, Dennis W. and Zalesny, Ronald S., Jr. and Nichols, Elizabeth Guthrie}, year={2021}, month={Jul} }
 @article{hedgespeth_mccord_phillips_strynar_shea_nichols_2021, title={Suspect-screening analysis of a coastal watershed before and after Hurricane Florence using high-resolution mass spectrometry}, volume={782}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2021.146862}, abstractNote={On September 14, 2018, Hurricane Florence delivered ~686 mm rainfall to a 106 km2 watershed in coastal North Carolina, USA. A forested land treatment site comprises one third of the watershed wherein municipal wastewater effluent is spray-irrigated onto 8.9 km2 of forest. This communication provides insight for land treatment function under excess water duress as well as changes in organic chemical composition in on- and off-site waters before (June 2018) and after (September & December 2018) Hurricane Florence's landfall. We compare the numbers and relative abundances of chemical features detected using suspect screening high resolution mass spectrometry in waste-, ground-, and surface water samples. Values for upstream and receiving waters in September were lower than for sampling events in June and December, indicating an expected dilution effect across the watershed. Chemical diversity was greatest for all surface water samples in December, but only upstream surface water showed a dramatic five-fold increase in relative chemical abundance. Chemical abundance in on-site water and downstream surface water was equal to or lower than the September storm dilution effect. These data suggest that the land treatment system is functionally and hydrologically robust to extreme storm events and contributed to dilution of upstream chemical reservoirs for downstream receiving waters for months after the storm. Similar systems may embody one water reuse strategy robust to the increasing occurrence of extreme precipitation events.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Hedgespeth, Melanie L. and McCord, James P. and Phillips, Katherine A. and Strynar, Mark J. and Shea, Damian and Nichols, Elizabeth Guthrie}, year={2021}, month={Aug} }
 @article{ghezehei_wright_zalesny_nichols_hazel_2020, title={Matching site-suitable poplars to rotation length for optimized productivity}, volume={457}, ISSN={0378-1127}, url={http://dx.doi.org/10.1016/j.foreco.2019.117670}, DOI={10.1016/j.foreco.2019.117670}, abstractNote={Diversity of applications, productivity potential, broad suitability and genetic variations make Populus a valuable fast-growing genus. Our goal was to assess if clonal site-suitability varies with rotation-length. We examined survival, growth (height, diameter at breast height) and estimated stem and total-wood (stem and branches) biomass of 89 clones near Fountain, North Carolina (35°42′7.52″ N, 77°34′35.04″ W) in the coastal southeastern USA at four- and eight-year rotations. The unsuitability of some clones was evident at early age while other clones became less suitable with stand age. Specifically, most mortality occurred by year-four, yet 25% clones experienced 17 to 50% mortality at older ages. Clone '379' was the most site-suitable with 100% survival and 141.3 kg total-wood per tree (approximately 47.5 Mg ha−1 yr−1). Moreover, several clones with low survival produced high per-hectare biomass. Biomass (stem and total-wood) rankings changed between four- and eight-year rotations with only three top-ten clones in year-four ('379', '402', '449') in the top-ten of year-eight and two top-ten clones in year-eight ('379', '402') also in the top-ten of year-four. Clonal productivity differences increased by 25 to 836% with age. Clones of TD (Populus trichocarpa Torr and Gray × P. deltoids Barts Ex Marsh) and DD (P. deltoides × P. deltoides) genotypes were affected by wood infection (Septoria musiva) indicating that selection based on disease resistance should be performed at clonal level. Hence, for productivity-focused stands, site-suitable clones should be selected by productivity first, then narrowed by survival and rotation length. Changes in the most 'site-suitable' clones can be expected between longer and shorter rotations.}, journal={Forest Ecology and Management}, publisher={Elsevier BV}, author={Ghezehei, Solomon B. and Wright, Jeff and Zalesny, Ronald S., Jr. and Nichols, Elizabeth Guthrie and Hazel, Dennis W.}, year={2020}, month={Feb}, pages={117670} }
 @article{gibson_sun_nichols_2020, title={Water balance of municipal wastewater irrigation in a coastal forested watershed}, volume={13}, ISSN={["1936-0592"]}, DOI={10.1002/eco.2227}, abstractNote={Abstract}, number={5}, journal={ECOHYDROLOGY}, author={Gibson, Nancy E. and Sun, Ge and Nichols, Elizabeth Guthrie}, year={2020}, month={Jul} }
 @article{ghezehei_nichols_maier_hazel_2019, title={Adaptability of Populus to Physiography and Growing Conditions in the Southeastern USA}, volume={10}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f10020118}, DOI={10.3390/f10020118}, abstractNote={Populus species have a high productivity potential as short-rotation woody crops, provided that site-suitable varieties are planted. The Coastal Plain, the Piedmont, and the Blue Ridge Mountains make up a significant part of the eastern and southeastern USA, and an insight into poplar productivity and adaptability will be valuable for the successful implementation of large-scale poplar stands in these regions. The objectives of this study were to examine the green wood biomass (hereafter biomass), biomass allocation, and wood properties of poplars in relation to growing conditions, physiography, and topography. The biomass of 4-year-old poplars was estimated using an equation derived through destructive sampling. Biomass-based clonal rankings were compared across the various site conditions (fertility, irrigation, land marginality, soil preparation, and topography) and the three physiographic provinces. Although not all clonal differences in biomass were significant, growing conditions, physiography, and soil preparation affected the clonal rankings and the significance of the clonal differences. Biomass changes due to physiography and land conditions were more structured at the genomic-group level. A higher-altitude physiography led to greater biomass increases in Populus trichocarpa × Populus deltoids (TD) clones than in P. deltoids × P. deltoids (DD) clones and vice versa. Favorable soil quality or management generally led to greater biomass of DD clones than of TD and P. deltoids × Populus maximowiczii (DM) clones. Weather-related variables were not clearly correlated with biomass, while land aspect was a significant influence on the biomass of genomic groups and clones. The site significantly affected wood density, moisture content, and carbon and nitrogen concentrations, while the clonal effects on wood composition and the clonal and site effects on biomass allocation were insignificant. Although clones showing greater biomass responses to growing conditions generally belonged to the same genomic group, clone-level selection could produce greater biomass gains than selection at the genomic-group level.}, number={2}, journal={Forests}, publisher={MDPI AG}, author={Ghezehei, Solomon and Nichols, Elizabeth and Maier, Christopher and Hazel, Dennis}, year={2019}, month={Feb}, pages={118} }
 @article{zalesny_headlee_gopalakrishnan_bauer_hall_hazel_isebrands_licht_negri_nichols_et al._2019, title={Ecosystem services of poplar at long‐term phytoremediation sites in the Midwest and Southeast, United States}, volume={8}, ISSN={2041-8396 2041-840X}, url={http://dx.doi.org/10.1002/wene.349}, DOI={10.1002/wene.349}, abstractNote={Abstract}, number={6}, journal={Wiley Interdisciplinary Reviews: Energy and Environment}, publisher={Wiley}, author={Zalesny, Ronald S. and Headlee, William L. and Gopalakrishnan, Gayathri and Bauer, Edmund O. and Hall, Richard B. and Hazel, Dennis W. and Isebrands, Jud G. and Licht, Louis A. and Negri, M. Cristina and Nichols, Elizabeth Guthrie and et al.}, year={2019}, month={Jun} }
 @article{hedgespeth_nichols_2019, title={Expanding phytoremediation to the realms of known and unknown organic chemicals of concern}, volume={21}, ISSN={1522-6514 1549-7879}, url={http://dx.doi.org/10.1080/15226514.2019.1633265}, DOI={10.1080/15226514.2019.1633265}, abstractNote={Abstract Recent advancements in analytical chemistry and data analyses via high-resolution mass spectrometry (HRMS) are evolving scientific understanding of the potential totality of organic chemical exposure and pollutant risk. This review addresses the importance of HRMS approaches, namely suspect screening and nontarget chemical analyses, to the realm of phytoremediation. These analytical approaches are not without caveats and constraints, but they provide an opportunity to understand in greater totality how plant-based technologies contribute, mitigate, and reduce organic chemical exposure across scales of experimental and system-level studies. These analytical tools can enlighten the complexity and efficacy of plant-contaminant system design and expand our understanding of biogenic and anthropogenic chemicals at work in phytoremediation systems. Advances in data analytics from biological sciences, such as metabolomics, are crucial to HRMS analysis. This review provides an overview of targeted, suspect screening, and nontarget HRMS approaches, summarizes the expanding knowledge of regulated and unregulated organic chemicals in the environment, addresses requisite HRMS instrumentation, analysis cost, uncertainty, and data processing techniques, and offers potential bridges of HRMS analyses to phytoremediation research and application.}, number={14}, journal={International Journal of Phytoremediation}, publisher={Informa UK Limited}, author={Hedgespeth, Melanie L. and Nichols, Elizabeth Guthrie}, year={2019}, month={Jul}, pages={1385–1396} }
 @article{zalesny_berndes_dimitriou_fritsche_miller_eisenbies_ghezehei_hazel_headlee_mola‐yudego_et al._2019, title={Positive water linkages of producing short rotation poplars and willows for bioenergy and phytotechnologies}, volume={8}, ISSN={2041-8396 2041-840X}, url={http://dx.doi.org/10.1002/WENE.345}, DOI={10.1002/WENE.345}, abstractNote={The production of short rotation woody crops (SRWCs) such as poplars and willows is a promising component of global bioenergy and phytotechnology portfolios. In addition to the provision of biomass feedstocks and pollution remediation, these trees and shrubs have been sustainably grown to conserve or utilize water in a variety of applications. Growing these woody plants for multiple uses supports many of the United Nation's Sustainable Development Goals (SDGs), especially Clean Water and Sanitation (SDG6) and Affordable and Clean Energy (SDG7). As a result, focusing on ecosystem services such as freshwater and biomass has become an important aspect of deploying these production systems across variable landscapes. The current review consists of an introduction of ecosystem services and the SDGs, as well as SRWCs and their applications. The middle section of the review contains case studies highlighting the positive water linkages of producing short rotation poplars and willows for bioenergy and phytotechnologies. The review concludes with a section that combines the common themes that are consistent among the case studies to address options for integrating new bioenergy feedstock production systems into rural and urban landscapes to promote environmental, social and economic sustainability.}, number={5}, journal={Wiley Interdisciplinary Reviews: Energy and Environment}, publisher={Wiley}, author={Zalesny, Ronald S., Jr and Berndes, Göran and Dimitriou, Ioannis and Fritsche, Uwe and Miller, Constance and Eisenbies, Mark and Ghezehei, Solomon and Hazel, Dennis and Headlee, William L. and Mola‐Yudego, Blas and et al.}, year={2019}, month={Apr} }
 @article{ghezehei_nichols_hazel_2019, title={Productivity and cost-effectiveness of short-rotation hardwoods on various land types in the southeastern USA}, volume={22}, ISSN={1522-6514 1549-7879}, url={http://dx.doi.org/10.1080/15226514.2019.1647404}, DOI={10.1080/15226514.2019.1647404}, abstractNote={Abstract Despite the growing need to produce energy crops, information on comprehensive feasibility of growing short-rotation woody crops (SRWCs) on non-contentious and less-utilized lands and lands transitioning from previous uses in the southeastern USA is limited. An assessment model (SRWC-PEAM) was developed and tested for assessing the feasibility of SRWCs on lands targeted for ecosystem-service enhancements based on land conditions, species, and stand and economic variables in the southeastern USA. Productivity and economic returns of sweetgum (Liquidambar styraciflua L.), sycamore (Platanus occidentalis L.), and poplar (Populus) stand differed due to land types, species’ adaptability and biomass potential, and optimal land-type-based management schemes. Poplar stands had the greatest biomass and the highest returns on all land types although returns from the three species on most land types were poor using current reported regional delivered prices. Irrigating stands increased yields but returns were poorer than from non-irrigated stands due to high costs of irrigation. Longer rotations resulted in greater biomass and returns and were more crucial for irrigated stands. Significantly higher feedstock prices and productivities are requisite for SRWC viability in the southeastern USA. SRWC-PEAM is a web-based tool and can accommodate other SRWC species and assessment of environmental services associated with SRWCs.}, number={1}, journal={International Journal of Phytoremediation}, publisher={Informa UK Limited}, author={Ghezehei, Solomon B. and Nichols, Elizabeth G. and Hazel, Dennis W.}, year={2019}, month={Aug}, pages={98–110} }
 @article{hedgespeth_gibson_mccord_strynar_shea_nichols_2019, title={Suspect screening and prioritization of chemicals of concern (COCs) in a forest-water reuse system watershed}, volume={694}, ISSN={0048-9697}, url={http://dx.doi.org/10.1016/j.scitotenv.2019.07.184}, DOI={10.1016/j.scitotenv.2019.07.184}, abstractNote={Much research has assessed organic chemicals of concern (COCs) in municipal wastewater and receiving waters, but few studies have examined COCs in land treatment systems. Many prior studies have implemented targeted methods that quantify a relatively small fraction of COCs present in wastewater and receiving waters. This study used suspect screening to assess chemical features in ground- and surface waters from a watershed where secondary-treated wastewater is irrigated onto 900 ha of temperate forest, offering a more holistic view of chemicals that contribute to the exposome. Chemical features were prioritized by abundance and ToxPi scoring across seasonal sampling events to determine if the forest-water reuse system contributed to the chemical exposome of ground- and surface waters. The number of chemical features detected in wastewater was usually higher than on- and off-site ground- and surface waters; in wastewater, chemical features trended with precipitation in which greater numbers of features were detected in months with low precipitation. The number of chemical features detected in off- and on-site waters was similar. The lower overlap between chemical features found in wastewater and downstream surface waters, along with the similar numbers of features being detected in upstream and downstream surface waters, suggests that though wastewater may be a source of chemicals to ground and surface waters on-site, dissipation of wastewater-derived features (in number and peak area abundance) likely occurs with limited off-site surface water export by the forested land treatment system. Further, the numbers of features detected on site and the overlap between wastewater and surface waters did not increase during periods of low rainfall, counter to our initial expectations. The chemical features tentatively identified in this watershed appear common to features identified in other studies, warranting further examination on the potential for resulting impacts of these on humans and the environment.}, journal={Science of The Total Environment}, publisher={Elsevier BV}, author={Hedgespeth, Melanie L. and Gibson, Nancy and McCord, James and Strynar, Mark and Shea, Damian and Nichols, Elizabeth Guthrie}, year={2019}, month={Dec}, pages={133378} }
 @article{maier_burley_cook_ghezehei_hazel_nichols_2019, title={Tree Water Use, Water Use Efficiency, and Carbon Isotope Discrimination in Relation to Growth Potential in Populus deltoides and Hybrids under Field Conditions}, volume={10}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f10110993}, DOI={10.3390/f10110993}, abstractNote={We explored the relationship between tree growth, water use, and related hydraulic traits in Populus deltoides Bartr. ex Marsh.and hybrid clones, to examine potential trade-offs between growth and water use efficiency. Nine genotypes, six P. deltoides and three hybrid clones, that represented genotypes with high (Group H), intermediate (Group I), and low (Group L) growth performance were selected for study, based on year-two standing stem biomass in a replicated field trial. In year four, tree growth, transpiration (Et), canopy stomatal conductance (Gs), whole-tree hydraulic conductance (Gp), and carbon isotope discrimination (Δ13C) were measured. Tree sap flux was measured continuously using thermal dissipation probes. We hypothesized that Group H genotypes would have increased growth efficiency (GE), increased water use efficiency of production (WUEp, woody biomass growth/Et), lower Δ13C, and greater Gp than slower growing genotypes. Tree GE increased with relative growth rate (RGR), and mean GE in Group H was significantly greater than L, but not I. Tree WUEp ranged between 1.7 and 3.9 kg biomass m3 H2O−1, which increased with RGR. At similar levels of Et, WUEp was significantly greater in Group H (2.45 ± 0.20 kg m−3), compared to I (2.03 ± 0.18 kg m−3) or L (1.72 ± 0.23 kg m−3). Leaf and wood Δ13C scaled positively with stem biomass growth but was not correlated with WUEp. However, at a similar biomass increment, clones in Group H and I had significantly lower leaf Δ13C than Group L. Similarly, Group H clones had a significantly lower wood Δ13C than Group L, supporting our hypothesis of increased WUE in larger trees. Tree physiological and hydraulic traits partially explain differences in WUEp and Δ13C, and suggest that clone selection and management activities that increase tree biomass production will likely increase tree and stand WUE. However, more research is needed to discern the underlying hydraulic mechanisms responsible for the higher WUE exhibited by large trees and distinct clones.}, number={11}, journal={Forests}, publisher={MDPI AG}, author={Maier and Burley and Cook and Ghezehei and Hazel and Nichols}, year={2019}, month={Nov}, pages={993} }
 @article{mceachran_hedgespeth_newton_mcmahen_strynar_shea_nichols_2018, title={Comparison of emerging contaminants in receiving waters downstream of a conventional wastewater treatment plant and a forest-water reuse system}, volume={25}, ISSN={0944-1344 1614-7499}, url={http://dx.doi.org/10.1007/s11356-018-1505-5}, DOI={10.1007/s11356-018-1505-5}, abstractNote={Forest-water reuse (FWR) systems treat municipal, industrial, and agricultural wastewaters via land application to forest soils. Previous studies have shown that both large-scale conventional wastewater treatment plants (WWTPs) and FWR systems do not completely remove many contaminants of emerging concern (CECs) before release of treated wastewater. To better characterize CECs and potential for increased implementation of FWR systems, FWR systems need to be directly compared to conventional WWTPs. In this study, both a quantitative, targeted analysis and a nontargeted analysis were utilized to better understand how CECs release to waterways from an FWR system compared to a conventional treatment system. Quantitatively, greater concentrations and total mass load of CECs was exhibited downstream of the conventional WWTP compared to the FWR. Average summed concentrations of 33 targeted CECs downstream of the conventional system were ~ 1000 ng/L and downstream of the FWR were ~ 30 ng/L. From a nontargeted chemical standpoint, more tentatively identified chemicals were present, and at a greater relative abundance, downstream of the conventional system as well. Frequently occurring contaminants included phthalates, pharmaceuticals, and industrial chemicals. These data indicate that FWR systems represent a sustainable wastewater treatment alternative and that emerging contaminant release to waterways was lower at a FWR system than a conventional WWTP.}, number={13}, journal={Environmental Science and Pollution Research}, publisher={Springer Science and Business Media LLC}, author={McEachran, Andrew D. and Hedgespeth, Melanie L. and Newton, Seth R. and McMahen, Rebecca and Strynar, Mark and Shea, Damian and Nichols, Elizabeth Guthrie}, year={2018}, month={Feb}, pages={12451–12463} }
 @article{mceachran_shea_nichols_2017, title={Pharmaceuticals in a temperate forest-water reuse system}, volume={581-582}, ISSN={0048-9697}, url={http://dx.doi.org/10.1016/j.scitotenv.2016.12.185}, DOI={10.1016/j.scitotenv.2016.12.185}, abstractNote={Forest-water reuse systems infiltrate municipal, industrial, and agricultural wastewaters through forest soils to shallow aquifers that ultimately discharge to surface waters. Their ability to mitigate regulated nutrients, metals, and organic chemicals is well known, but the fate of non-regulated chemicals in these systems is largely unstudied. This study quantified 33 pharmaceuticals and personal care products (PPCPs) in soils, groundwaters, and surface waters in a 2000-hectare forest that receives ~1200mm/year of secondary-treated, municipal wastewater in addition to natural rainfall (~1300mm/year). This forest-water reuse system does contribute PPCPs to soils, groundwater, and surface waters. PPCPs were more abundant in soils versus underlying groundwater by an order of magnitude (5-10ng/g summed PPCPs in soil and 50-100ng/L in groundwater) and the more hydrophobic chemicals were predominant in soil over water. PPCP concentrations in surface waters were greater at the onset of significant storm events and during low-rainfall periods when total summed PPCPs were >80ng/L, higher than the annual average. With few exceptions, the margins of exposure for PPCPs in groundwater and surface waters were several orders of magnitude above values indicative of human health risk.}, journal={Science of The Total Environment}, publisher={Elsevier BV}, author={McEachran, Andrew D. and Shea, Damian and Nichols, Elizabeth Guthrie}, year={2017}, month={Mar}, pages={705–714} }
 @article{shifflett_culbreth_hazel_daniels_nichols_2016, title={Coupling aquaculture with forest plantations for food, energy, and water resiliency}, volume={571}, ISSN={0048-9697}, url={http://dx.doi.org/10.1016/j.scitotenv.2016.07.161}, DOI={10.1016/j.scitotenv.2016.07.161}, abstractNote={Freshwater aquaculture and forest bioenergy markets are expanding globally in areas concurrently experiencing human population growth, urbanization and water shortages. Coupling these agroecosystems can improve food, energy, and water resiliency by enhancing ecosystem services through fertilization, water-reuse, carbon storage, and bioenergy via biomass production. This study evaluated how a model aquaculture-managed forest plantation could (1) provision fish and woody biomass; (2) regulate carbon, groundwater infiltration, and groundwater quality; and (3) support nutrient cycling over a two-year period. A 0.5-hectare hardwood bioenergy plantation was established with 12 Populus spp. genotypes adjacent to a 0.6-hectare freshwater aquaculture operation (hybrid striped bass, Morone chrysops×M. saxatilis); pond waters were land-applied on the plantation for two years. The aquaculture operation produced ~3.5Mg of fish and trees yielded 5.9Mgha(-1)yr(-1) of oven-dry biomass, sequestered 2.9Mg carbon (C) ha(-1)yr(-1) and stored 0.028Mg nitrogen (N) ha(-1)yr(-1). Biomass productivity, carbon storage, and nitrogen storage differed significantly among the evaluated Populus genotypes. Land application of pond water increased groundwater infiltration by 60% relative to the previous year. The integrated system regulated chlorophyll a, total organic carbon, and nitrogen in groundwater at concentrations below regulatory limits. This study demonstrated that coupled agroecosystems could deliver productive yields of food and bioenergy as well as support water re-use while meeting water quality regulations. More research is needed to evaluated long-term sustainability and economic viability of this coupled system and other land management practices that seek to improve food, energy, and water resiliency.}, journal={Science of The Total Environment}, publisher={Elsevier BV}, author={Shifflett, Shawn Dayson and Culbreth, Allison and Hazel, Dennis and Daniels, Harry and Nichols, Elizabeth Guthrie}, year={2016}, month={Nov}, pages={1262–1270} }
 @inbook{nichols_2016, title={Current and Future Opportunities for Forest Land Application Systems of Wastewater}, ISBN={9783319418100 9783319418117}, url={http://dx.doi.org/10.1007/978-3-319-41811-7_9}, DOI={10.1007/978-3-319-41811-7_9}, booktitle={Phytoremediation}, publisher={Springer International Publishing}, author={Nichols, Elizabeth Guthrie}, year={2016}, pages={153–173} }
 @article{ghezehei_nichols_hazel_2016, title={Early Clonal Survival and Growth of Poplars Grown on North Carolina Piedmont and Mountain Marginal Lands}, volume={9}, ISSN={1939-1234 1939-1242}, url={http://dx.doi.org/10.1007/s12155-015-9707-x}, DOI={10.1007/s12155-015-9707-x}, number={2}, journal={BioEnergy Research}, publisher={Springer Science and Business Media LLC}, author={Ghezehei, Solomon B. and Nichols, Elizabeth Guthrie and Hazel, Dennis W.}, year={2016}, month={Jun}, pages={548–558} }
 @article{birch_emanuel_james_nichols_2016, title={Hydrologic Impacts of Municipal Wastewater Irrigation to a Temperate Forest Watershed}, volume={45}, ISSN={0047-2425}, url={http://dx.doi.org/10.2134/jeq2015.11.0577}, DOI={10.2134/jeq2015.11.0577}, abstractNote={Land application of municipal wastewater to managed forests is an important treatment and water reuse technology used globally, but the hydrological processes of these systems are not well characterized for temperate areas with annual rainfall of 1200 mm or greater. This study evaluated the impact of municipal wastewater irrigation to the local water balance at a 3000‐ha land application facility where secondary‐treated wastewater is land applied to a mixed hardwood–pine forest over 900 ha. Stable isotopes of hydrogen (2H) and oxygen (18O), chloride concentrations, and specific conductance were used in combination with hydrometric measurements to estimate the wastewater composition in groundwater, surface water, and at the watershed outlet during dry and wet seasonal periods and during one large rainfall event. Wastewater and water bodies receiving irrigation were found to have significantly higher δ2H, δ18O, specific conductance, and chloride concentrations. Using these tracers, a two‐component, three‐end member geochemical mixing model estimated mean wastewater compositions in the surficial aquifer receiving irrigation from 47 to 73%. Surface water onsite was found to reflect the high wastewater composition in groundwater. Land‐applied wastewater contributed an estimated 24% of total streamflow, with the highest wastewater compositions in surface water observed during major storm events and at low‐flow conditions. Groundwater and surface water within the watershed were found to have proportionally higher wastewater compositions than expected based on the proportion of irrigation to rainfall received by these areas.}, number={4}, journal={Journal of Environmental Quality}, publisher={Wiley}, author={Birch, Andrew L. and Emanuel, Ryan E. and James, April L. and Nichols, Elizabeth Guthrie}, year={2016}, month={Jul}, pages={1303–1312} }
 @article{shifflett_hazel_guthrie nichols_2016, title={Sub-Soiling and Genotype Selection Improves Populus Productivity Grown on a North Carolina Sandy Soil}, volume={7}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f7040074}, DOI={10.3390/f7040074}, abstractNote={This study reports the stem volume of 10 Populus genotypes in a randomized split-plot design with different tillage treatments (disking versus sub-soiling) after two years of growth. Height, diameter at breast height (DBH), stem aboveground volume index, survival, Melampsora rust resistance, leaf area index (LAI), chlorophyll content, and foliar nitrogen concentration (Foliar N) were measured to identify how tillage treatments might alter poplar growth. Stem volume index and LAI were positively correlated and differed significantly among tillage treatments, taxa, and genotypes. Melampsora rust resistance was also positively correlated with volume index, but significant differences were only detected among taxa and genotypes. Foliar N and chlorophyll did not correlate to stem volume for genotypes or tillage treatments. Overall, sub-soiling yielded 37% more estimated volume compared to disking. Within the sub-soiled treatments, four genotypes (140, 176, 185, and 356) had high survival (>80%) and produced substantial stem volume (>32 dm3·tree−1). These findings show that tillage practices do impact poplar stem volumes after two years and that sub-soiling improves productivity for poplar short rotation woody crops on loamy fine-sandy soils.}, number={12}, journal={Forests}, publisher={MDPI AG}, author={Shifflett, Shawn and Hazel, Dennis and Guthrie Nichols, Elizabeth}, year={2016}, month={Mar}, pages={74} }
 @article{nichols_deluca_ebersohl_2015, title={Multi-Institutional Collaboration for a Shared Renewable Energy Assessment Curriculum}, volume={44}, DOI={10.4195/nse2014.10.0023}, abstractNote={The growth of renewable energy markets in North Carolina (USA) requires workforce expertise. Natural resource majors are well-poised to contribute to future workplace needs, particularly to assess landscapes for appropriate renewable energy use, to evaluate the impact of renewable energy technologies on natural resources, and to manage renewable energy sites with regard to natural resource sustainability. The objective of this project is to establish a shared curriculum for Renewable Energy Assessment to support an online Undergraduate Certificate in Renewable Energy Assessment and minor at North Carolina State University (NC State), a 2-year Associate's Degree at Cape Fear Community College (CFCC), and an undergraduate minor at Elizabeth City State University (ECSU). We report on the development, implementation, and initial assessment of a multi- institutional curriculum developed between a historically black university (HBU), a community college, and a research-intensive university in North Carolina. After 2 years, the project has impacted 11 faculty (7 at NC State University, 2 at CFCC, and 2 at ECSU) and 197 students, collaboratively created three new courses, collectively revised three existing courses, and created one undergraduate online certificate and two undergraduate minors. Initial demographic assessment data show that each institution helps diversify student participation in the curriculum as a whole for gender, ethnicity, and age.}, journal={Natural Sciences Education}, author={Nichols, Elizabeth and DeLuca, V.W. and Ebersohl, R.}, year={2015} }
 @article{mceachran_shea_bodnar_nichols_2015, title={Pharmaceutical occurrence in groundwater and surface waters in forests land-applied with municipal wastewater}, volume={35}, ISSN={0730-7268}, url={http://dx.doi.org/10.1002/etc.3216}, DOI={10.1002/etc.3216}, abstractNote={Abstract}, number={4}, journal={Environmental Toxicology and Chemistry}, publisher={Wiley}, author={McEachran, Andrew D. and Shea, Damian and Bodnar, Wanda and Nichols, Elizabeth Guthrie}, year={2015}, month={Dec}, pages={898–905} }
 @article{steelman_nichols_james_bradford_ebersöhn_scherman_omidire_bunn_twine_mchale_2015, title={Practicing the science of sustainability: the challenges of transdisciplinarity in a developing world context}, volume={10}, ISSN={1862-4065 1862-4057}, url={http://dx.doi.org/10.1007/s11625-015-0334-4}, DOI={10.1007/s11625-015-0334-4}, number={4}, journal={Sustainability Science}, publisher={Springer Science and Business Media LLC}, author={Steelman, Toddi and Nichols, Elizabeth Guthrie and James, April and Bradford, Lori and Ebersöhn, Liesel and Scherman, Vanessa and Omidire, Funke and Bunn, David N. and Twine, Wayne and McHale, Melissa R.}, year={2015}, month={Sep}, pages={581–599} }
 @article{ghezehei_shifflett_hazel_nichols_2015, title={SRWC bioenergy productivity and economic feasibility on marginal lands}, volume={160}, ISSN={["1095-8630"]}, DOI={10.1016/j.jenvman.2015.05.025}, abstractNote={Evolving bioenergy markets necessitate consideration of marginal lands for woody biomass production worldwide particularly the southeastern U.S., a prominent wood pellet exporter to Europe. Growing short rotation woody crops (SRWCs) on marginal lands minimizes concerns about using croplands for bioenergy production and reinforces sustainability of wood supply to existing and growing global biomass markets. We estimated mean annual aboveground green biomass increments (MAIs) and assessed economic feasibility of various operationally established (0.5 ha-109 ha) SRWC stands on lands used to mitigate environmental liabilities of municipal wastewater, livestock wastewater and sludge, and subsurface contamination by petroleum and pesticides. MAIs (Mg ha(-1) yr(-1)) had no consistent relationship with stand density or age. Non-irrigated Populus, Plantanus occidentalis L. and Pinus taeda L. stands produced 2.4-12.4 Mg ha(-1) yr(-1). Older, irrigated Taxodium distchum L., Fraxinus pennsylvanica L., and coppiced P. occidentalis stands had higher MAIs (10.6-21.3 Mg ha(-1) yr(-1)) than irrigated Liquidambar styraciflua L. and non-coppiced, irrigated P. occidentalis (8-18 Mg ha(-1) yr(-1)). Natural hardwood MAIs at 20-60 years were less than hardwood and P. taeda productivities at 5-20 years. Unlike weed control, irrigation and coppicing improved managed hardwood productivity. Rotation length affected economic outcomes although the returns were poor due to high establishment and maintenance costs, low productivities and low current stumpage values, which are expected to quickly change with development of robust global markets.}, journal={JOURNAL OF ENVIRONMENTAL MANAGEMENT}, publisher={Elsevier BV}, author={Ghezehei, Solomon B. and Shifflett, Shawn D. and Hazel, Dennis W. and Nichols, Elizabeth Guthrie}, year={2015}, month={Sep}, pages={57–66} }
 @inproceedings{wilcox_guthrie nichols_2014, title={Pharmaceuticals in the environment: Review of current disposal practices for medications and the influence of public perception on environmental risks.}, booktitle={ NC AWWA-WEA Annual Conference}, author={Wilcox, E. and Guthrie Nichols, E.}, year={2014} }
 @article{nichols_cook_landmeyer_atkinson_malone_shaw_woods_2014, title={Phytoremediation of a Petroleum-Hydrocarbon Contaminated Shallow Aquifer in Elizabeth City, North Carolina, USA}, volume={24}, ISSN={1051-5658}, url={http://dx.doi.org/10.1002/rem.21382}, DOI={10.1002/rem.21382}, abstractNote={A former bulk fuel terminal in North Carolina is a groundwater phytoremediation demonstration site where 3,250 hybrid poplars, willows, and pine trees were planted from 2006 to 2008 over approximately 579,000 L of residual gasoline, diesel, and jet fuel. Since 2011, the groundwater altitude is lower in the area with trees than outside the planted area. Soil‐gas analyses showed a 95 percent mass loss for total petroleum hydrocarbons (TPH) and a 99 percent mass loss for benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX and methyl tert‐butyl ether concentrations have decreased in groundwater. Interpolations of free‐phase, fuel product gauging data show reduced thicknesses across the site and pooling of fuel product where poplar biomass is greatest. Isolated clusters of tree mortalities have persisted in areas with high TPH and BTEX mass. Toxicity assays showed impaired water use for willows and poplars exposed to the site's fuel product, but Populus survival was higher than the willows or pines on‐site, even in a noncontaminated control area. All four Populus clones survived well at the site. © 2014 Wiley Periodicals, Inc.*}, number={2}, journal={Remediation Journal}, publisher={Wiley}, author={Nichols, Elizabeth Guthrie and Cook, Rachel L. and Landmeyer, James E. and Atkinson, Brad and Malone, Donald R. and Shaw, George and Woods, Leilani}, year={2014}, month={Mar}, pages={29–46} }
 @article{shifflett_hazel_frederick_nichols_2013, title={Species Trials of Short Rotation Woody Crops on Two Wastewater Application Sites in North Carolina, USA}, volume={7}, ISSN={1939-1234 1939-1242}, url={http://dx.doi.org/10.1007/s12155-013-9351-2}, DOI={10.1007/s12155-013-9351-2}, number={1}, journal={BioEnergy Research}, publisher={Springer Science and Business Media LLC}, author={Shifflett, Shawn Dayson and Hazel, Dennis W and Frederick, Douglas J and Nichols, Elizabeth Guthrie}, year={2013}, month={Jul}, pages={157–173} }
 @article{cook_landmeyer_atkinson_messier_nichols_2010, title={Field Note: Successful Establishment of a Phytoremediation System at a Petroleum Hydrocarbon Contaminated Shallow Aquifer: Trends, Trials, and Tribulations}, volume={12}, ISSN={["1549-7879"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77956951220&partnerID=MN8TOARS}, DOI={10.1080/15226510903390395}, abstractNote={We report the establishment of a mixed hybrid poplar (Populus spp.) and willow (Salix spp.) phytoremediation system at a fuel-contaminated site. Several approaches were used to balance competing goals of cost-effectiveness yet successful tree establishment without artificial irrigation or trenching. Bare root and unrooted cuttings were installed using either: (1) 1.2 m deep holes excavated with an 8 cm diameter auger using a direct-push rig and backfilled with the excavated, in situ soil; (2) 1.2 m deep holes created with a 23 cm diameter auger attached to a Bobcat rig and backfilled with clean topsoil from offsite; and (3) shallow holes between 15–30 cm deep that were created with a 1.3 cm diameter rod and no backfill. Tree mortality from initial plantings indicated contaminated zones not quantified in prior site investigations and remedial actions. Aquifer heterogeneity, underground utilities, and prior remediation infrastructure hampered the ability of the site to support a traditional experimental design. Total stem length and mortality were measured for all planted trees and were incorporated into a geographic information system. Planting early in the growing season, augering a larger diameter hole, and backfilling with clean, uncontaminated topsoil was cost effective and allowed for greater tree cutting growth and survival.}, number={7}, journal={INTERNATIONAL JOURNAL OF PHYTOREMEDIATION}, author={Cook, Rachel L. and Landmeyer, James E. and Atkinson, Brad and Messier, Jean-Pierre and Nichols, Elizabeth Guthrie}, year={2010}, pages={716–732} }
 @article{nichols_musella_2009, title={Differences in PAH desorption and sediment organic matter composition between non-vegetated and recently vegetated fuel-oiled sediments}, volume={11}, DOI={10.1080/15226510802656128}, abstractNote={We assessed the desorption behavior of pyrene, chrysene, phenanthrene, and tri-alkylated (C3) phenanthrene/anthracenes for non-vegetated and recently vegetated (< 2 yrs) fuel-oiled sediments collected from the Indiana Harbor Canal (IHC), Gary, IN. Bulk sediment and humin were analyzed for PAH concentrations, organic matter composition, and PAH desorption behavior. PAH desorption isotherms and kinetics were determined using batch aqueous extractions and a two compartment, first-order kinetic model. Vegetated sediments contained more plant carbon and were more nonpolar and less oxidized than non-vegetated sediments. Desorption kinetics indicated that PAH desorption was primarily controlled by a slow PAH-desorbing fraction (F2) of IHC sediments. However, in vegetated sediments, particularly humin, PAH release from a faster PAH-desorbing fraction (F1) increased as did the rates (k2) of PAH desorption from the dominant slow PAH-desorbing fraction (F2). We propose that vegetation provides aliphatic, nonpolar carbon to IHC sediments that facilitates more rapid PAH desorption from bulk sediment and humin.}, journal={International Journal of Phytoremediation}, author={Nichols, Elizabeth and Musella, J.}, year={2009}, pages={463–478} }
 @article{gregory_nichols_2008, title={Differences in sediment organic matter composition and PAH weathering between non-vegetated and recently vegetated fuel oiled sediments}, volume={10}, ISSN={["1549-7879"]}, DOI={10.1080/15226510802114862}, abstractNote={We examined polycyclic aromatic hydrocarbon (PAH) attenuation in contaminated field sediments after only 2 years of plant growth. We collected sediments from vegetated and non-vegetated areas at the Indiana Harbor Canal (IHC), an industrialized area with historic petroleum contamination of soils and sediments. PAH concentrations, PAH weathering indices, and organic matter composition in sediments colonized by Phragmites, cattails, or willow trees were compared to the same indices for non-vegetated sediments. We hypothesized that bulk sediment and humin fractions with measurable increases in plant organic matter content would show measurable changes to PAH attenuation as indicated by more weathered PAH diagnostic ratios or reduced PAH concentrations. Carbon-normalized PAH concentrations were lower in vegetated bulk sediments but higher in vegetated humin fractions relative to non-vegetated sediment fractions. Total organic carbon content was not indicative of more weathered N3/P2 ratios or reduced PAH concentrations in vegetated sediment fractions. More weathered N3/P2 ratios were observed with increased modern carbon (plant carbon) content of vegetated sediment fractions. Phragmites sediments contained more modern carbon (plant carbon) and more weathered PAH ratios [C3-naphthalenes and C2-phenanthrenes (N3/P2)] than willow, cattail, and non-vegetated sediments.}, number={6}, journal={INTERNATIONAL JOURNAL OF PHYTOREMEDIATION}, author={Gregory, Samuel T., III and Nichols, Elizabeth Guthrie}, year={2008}, pages={473–485} }
 @article{nichols_gregory_musella_2008, title={The impact of vegetation on sedimentary organic matter composition and PAH desorption}, volume={156}, ISSN={["0269-7491"]}, DOI={10.1016/j.envpol.2008.05.011}, abstractNote={Relationships between sedimentary organic matter (SOM) composition and PAH desorption behavior were determined for vegetated and non-vegetated refinery distillate waste sediments. Sediments were fractionated into size, density, and humin fractions and analyzed for their organic matter content. Bulk sediment and humin fractions differed more in organic matter composition than size/density fractions. Vegetated humin and bulk sediments contained more polar organic carbon, black carbon, and modern (plant) carbon than non-vegetated sediment fractions. Desorption kinetics of phenanthrene, pyrene, chrysene, and C(3)-phenanthrene/anthracenes from humin and bulk sediments were investigated using Tenax beads and a two-compartment, first-order kinetic model. PAH desorption from distillate waste sediments appeared to be controlled by the slow desorbing fractions of sediment; rate constants were similar to literature values for k(slow) and k(very slow). After several decades of plant colonization and growth (Phragmites australis), vegetated sediment fractions more extensively desorbed PAHs and had faster desorption kinetics than non-vegetated sediment fractions.}, number={3}, journal={ENVIRONMENTAL POLLUTION}, author={Nichols, Elizabeth Guthrie and Gregory, Samuel T. and Musella, Jennifer S.}, year={2008}, month={Dec}, pages={928–935} }
 @article{sharpe_nichols_2007, title={Use of stable nitrogen isotopes and permeable membrane devices to study what factors influence freshwater mollusk survival in the Conasauaga river}, volume={132}, ISSN={["1573-2959"]}, DOI={10.1007/s10661-006-9533-x}, abstractNote={Recent biological inventory data shows severe declines in freshwater mussel abundance and biodiversity in the Conasauga River Basin in Northwest Georgia, USA. Based on assessments of habitat conditions, mussel populations should be sustainable. We conducted a study of sediment and water quality to evaluate the impact of anthropogenic contamination on mussel populations. Permeable membrane devices (PMD), polar organic chemical integrative samplers (POCIS), conventional water and sediment quality analyses, and stable nitrogen isotope ratio analyses (delta15N) of snails and sediments were used to assess sediment and water quality at target sites throughout the basin. Ambient concentrations of organic contaminants in water were well below any aquatic life criteria; concentrations of some nutrients were detected above aquatic life criteria levels. Most mussel species in the river are endangered or threatened; therefore, snails were collected for delta15N analyses. Mean delta15N values for snails collected at forested upper watershed sites (national forest areas) were significantly lower than delta15N values from snails in agricultural areas. Delta15N values for raw cow manure and manure-treated soil were similar to delta15N values for snails collected in agricultural areas. Dissolved nitrate from water samples had elevated delta15N values similar to the upper range of delta15N values for snails in agricultural areas. Data, particularly stable nitrogen isotope data, indicates that a land use change from national forest land to agriculture alters nitrogen sources to the basin and snails. Implications of nutrient release on freshwater molluscan reproduction, growth, and survival are discussed.}, number={1-3}, journal={ENVIRONMENTAL MONITORING AND ASSESSMENT}, author={Sharpe, Adam J. and Nichols, Elizabeth Guthrie}, year={2007}, month={Sep}, pages={275–295} }
 @article{gregory_shea_guthrie-nichols_2005, title={Impact of vegetation on sedimentary organic matter composition and polycyclic aromatic hydrocarbon attenuation}, volume={39}, ISSN={["1520-5851"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-22344433253&partnerID=MN8TOARS}, DOI={10.1021/es048028o}, abstractNote={Results from natural and engineered phytoremediation systems provide strong evidencethatvegetated soils mitigate polycyclic aromatic hydrocarbon (PAH) contamination. However, the mechanisms by which PAH mitigation occurs and the impact of plant organic matter on PAH attenuation remain unclear. This study assessed the impact of plant organic matter on PAH attenuation in labile and refractory sediments fractions from a petroleum distillate waste pit that has naturally revegetated. Samples were collected in distinct zones of barren and vegetated areas to assess changes to organic matter composition and PAH content as vegetation colonized and became established in the waste pit. Sediments were fractionated into bulk sediment and humin fractions and analyzed for organic matter composition by isotope ratio mass spectrometry (delta (13)C), 13C nuclear magnetic resonance (13C NMR), delta 14C AMS (accelerator mass spectrometry), and percent organic carbon (%TOC). Gas chromatography mass spectrometry (GC/ MS) of lipid extracts of SOM fractions provided data for PAH distribution histograms, compound weathering ratios, and alkylated and nonalkylated PAH concentrations. Inputs of biogenic plant carbon, PAH weathering, and declines in PAH concentrations are most evidentfor vegetated SOM fractions, particularly humin fractions. Sequestered PAH metabolites were also observed in vegetated humin. These results show that plant organic matter does impact PAH attenuation in both labile and refractory fractions of petroleum distillate waste.}, number={14}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Gregory, ST and Shea, D and Guthrie-Nichols, E}, year={2005}, month={Jul}, pages={5285–5292} }
 @article{guthrie-nichols_grasham_kazunga_sangaiah_gold_bortiatynski_salloum_hatcher_2003, title={The effect of aging on pyrene transformation in sediments}, volume={22}, ISSN={["1552-8618"]}, DOI={10.1002/etc.5620220106}, abstractNote={Abstract}, number={1}, journal={ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY}, author={Guthrie-Nichols, E and Grasham, A and Kazunga, C and Sangaiah, R and Gold, A and Bortiatynski, J and Salloum, M and Hatcher, P}, year={2003}, month={Jan}, pages={40–49} }
 @article{greenwood_van heemst_guthrie_hatcher_2002, title={Laser micropyrolysis GC–MS of lignin}, volume={62}, ISSN={0165-2370}, url={http://dx.doi.org/10.1016/s0165-2370(01)00135-8}, DOI={10.1016/s0165-2370(01)00135-8}, abstractNote={The potential for using lasers as a highly directional thermal source in analytical pyrolysis studies is further investigated by the laser micropyrolysis GC–MS analysis of lignin moieties. Two woods representative of the main types of lignin (i.e. gymnosperm/guaiacyl producing and angiosperm/syringyl and guaiacyl producing) were separately analysed by both laser micropyrolysis GC–MS and the longer used pyroprobe pyrolysis GC–MS. High levels of correlation were observed from the laser and pyroprobe pyrograms of both lignins.}, number={2}, journal={Journal of Analytical and Applied Pyrolysis}, publisher={Elsevier BV}, author={Greenwood, Paul F. and van Heemst, Jasper D.H. and Guthrie, Elizabeth A. and Hatcher, Patrick G.}, year={2002}, month={Feb}, pages={365–373} }
 @article{chefetz_deshmukh_hatcher_guthrie_2000, title={Pyrene Sorption by Natural Organic Matter}, volume={34}, ISSN={0013-936X 1520-5851}, url={http://dx.doi.org/10.1021/es9912877}, DOI={10.1021/es9912877}, abstractNote={Sorption of pyrene on various types of natural organic matter (NOM) varying in chemical composition (e.g. high aliphaticity or aromaticity) was examined in batch sorption studies. The NOM samples (cuticle, humin, humic acid, degraded lignin, peat and lignite) were characterized by elemental analyses and solid-state 13C NMR spectra. Previous studies on polycyclic aromatic hydrocarbons (PAHs) sorption on soils and sediments led to the conclusion that aromatic component of the NOM determines the binding of nonionic compounds and that the polarity of the NOM reduces the binding coefficient of the aromatic NOM moieties. In this study we tested the hypothesis that aliphatic moieties of NOM derived from soils or sediments can contribute significantly to the binding of PAHs in aqueous media. Cuticle and a humin sample from an algal deposit exhibited the highest distribution coefficients (Koc). Both samples were rich in aliphatic structures and had very low aromaticity (4.6 and 8.8% for cuticle and humin samples, ...}, number={14}, journal={Environmental Science & Technology}, publisher={American Chemical Society (ACS)}, author={Chefetz, Benny and Deshmukh, Ashish P. and Hatcher, Patrick G. and Guthrie, Elizabeth A.}, year={2000}, month={Jul}, pages={2925–2930} }
 @article{greenwood_guthrie_hatcher_2000, title={The in situ analytical pyrolysis of two different organic components of a synthetic environmental matrix doped with [4,9-13C] pyrene}, volume={31}, ISSN={0146-6380}, url={http://dx.doi.org/10.1016/s0146-6380(00)00048-6}, DOI={10.1016/s0146-6380(00)00048-6}, abstractNote={Abstract Laser micropyrolysis GC–MS was used for in situ analysis of the coal and lignin components of a synthetic mixture. Designed to mimic environmental matrices such as soils and sediments, the mix comprised several possible soil precursors and was also amended with [4,9- 13 C]pyrene as part of concurrent research on the interaction of PAH pollutants and sedimentary organic matter. The labeled spike was consistently detected as the major pyrolysate in the in situ analyses of both lignin and coal components of the synthetic mix, indicating its effective sorption by these moieties of the mix. The remaining hydrocarbon distribution detected from the lignin was dominated by guiaicyl (i.e. methoxyphenol) compounds, whereas high abundances of aromatic (e.g. benzene, naphthalene, phenol and alkyl derivatives thereof) and aliphatic (e.g. n- alkene/alkane, prist-1-ene, hopanes) products were detected in the coal. Apart from the high concentrations of the 13 C-spike, these data were very similar to molecular data obtained from the respective pyroprobe pyrolysis GC–MS analysis of pure lignin and coal samples. The untainted (i.e. apart from the 13 C-spike) molecular signatures detected from the in situ analysis of the coal and lignin constituents indicates minimal organic contamination from the other constituents of the synthetic mix, successfully demonstrating the capability of the laser micropyrolysis GC–MS technique to selectively analyse the discrete organic entities within complex and heterogeneous mixtures.}, number={7-8}, journal={Organic Geochemistry}, publisher={Elsevier BV}, author={Greenwood, Paul F. and Guthrie, Elizabeth A. and Hatcher, Patrick G.}, year={2000}, month={Jul}, pages={635–643} }
 @article{guthrie_bortiatynski_van heemst_richman_hardy_kovach_hatcher_1999, title={Determination of [13C]Pyrene Sequestration in Sediment Microcosms Using Flash Pyrolysis−GC−MS and13C NMR}, volume={33}, ISSN={0013-936X 1520-5851}, url={http://dx.doi.org/10.1021/es980515e}, DOI={10.1021/es980515e}, abstractNote={In this study, the use of a 13C-labeled pollutant probe, [13C]pyrene, and the application of flash pyrolysis−GC−MS and CPMAS 13C NMR provided analytical capabilities to study pyrene interactions with soluble and insoluble compartments of sedimentary organic matter (SDOM) during whole sediments incubations in aerated microcosms. Surface sediments were collected from a site of previous hydrocarbon contamination in New Orleans, LA. Over a period of 60 days, humic acid and humin fractions of SDOM accumulated increasing amounts of pyrene that were resistant to exhaustive extraction with organic solvents. The sequestered pyrene was evident in CPMAS 13C NMR spectra of humin fractions. The amount of sequestered pyrene in humic materials was quantified by flash pyrolysis−GC−MS, a technique that destroys the three-dimensional structure of macromolecular SDOM. Noncovalent binding of pyrene to humic materials in SDOM was greater in sediments incubated with biological activity than biocide-treated sediments. The combi...}, number={1}, journal={Environmental Science & Technology}, publisher={American Chemical Society (ACS)}, author={Guthrie, Elizabeth A. and Bortiatynski, Jaqueline M. and van Heemst, Jasper D. H. and Richman, Jack E. and Hardy, Kristine S. and Kovach, Eugene M. and Hatcher, Patrick G.}, year={1999}, month={Jan}, pages={119–125} }
 @article{guthrie_pfaender_1998, title={Reduced Pyrene Bioavailability in Microbially Active Soils}, volume={32}, ISSN={0013-936X 1520-5851}, url={http://dx.doi.org/10.1021/es970670d}, DOI={10.1021/es970670d}, abstractNote={The influence of microbial activity on pyrene biodegradation and fate was assessed by quantifying the distribution of 14C-label and pyrene among soil organic matter fractions (SOM) in soils that contained varied microbial communities. A southern, hardwood forest soil was incubated with pyrene in aerated chambers for 9 months. Soil was incubated in three sets:  soil alone, soil augmented with a pyrene-degrading community, and soil inhibited with sodium azide (NaN3). After 9 months, pyrene mineralization was observed only in the degrader-amended soil set. Most of the pyrene and [14C]pyrene in the NaN3-amended soil set was recovered by solvent extraction (>75%). The [14C]pyrene extracted from the NaN3-amended soil set was mineralized by a microbial community shown to mineralize pyrene. Extractable pyrene from nonamended soil and degrader-amended soil sets decreased with time due to biodegradation. Extracted label from these soils was not mineralized to the same extent as NaN3-amended soil. Nonextractable lab...}, number={4}, journal={Environmental Science & Technology}, publisher={American Chemical Society (ACS)}, author={Guthrie, Elizabeth A. and Pfaender, Frederick K.}, year={1998}, month={Feb}, pages={501–508} }
 @article{walton_anderson_guthrie_1995, title={Letter to the Editor}, journal={Environmental Science & Technology}, author={Walton, B.T. and Anderson, T.A. and Guthrie, E.A.}, year={1995}, month={Feb} }
 @article{anderson_guthrie_walton_1993, title={Bioremediation in the rhizosphere.}, volume={27}, ISSN={0013-936X 1520-5851}, url={http://dx.doi.org/10.1021/es00049a001}, DOI={10.1021/es00049a001}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBioremediation in the rhizosphere.Todd A. Anderson, Elizabeth A. Guthrie, and Barbara T. WaltonCite this: Environ. Sci. Technol. 1993, 27, 13, 2630–2636Publication Date (Print):December 1, 1993Publication History Published online1 May 2002Published inissue 1 December 1993https://doi.org/10.1021/es00049a001RIGHTS & PERMISSIONSArticle Views2926Altmetric-Citations487LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (9 MB) Get e-Alerts Get e-Alerts}, number={13}, journal={Environmental Science & Technology}, publisher={American Chemical Society (ACS)}, author={Anderson, Todd A. and Guthrie, Elizabeth A. and Walton, Barbara T.}, year={1993}, month={Dec}, pages={2630–2636} }