@article{arenas_spence_nilon_leggett_2022, title={Diversifying the Field of Forestry Through a Graduate Fellowship Program: A Pilot Study on the Expectations of Students of Color}, volume={8}, ISSN={["1938-3746"]}, url={https://doi.org/10.1093/jofore/fvac024}, DOI={10.1093/jofore/fvac024}, abstractNote={Abstract Overall interest and involvement in forestry is relatively low for students of color compared to other STEM programs. This exploratory study aims to further understand the reasons graduate students of color in a National Needs Fellowship (NNF) program decide to pursue a career in forestry. Initial survey data showed that graduate students of color are motivated by pursuing specific forestry topics in the field while also having differing expectations with regard to career and financial opportunities. The results of this study could provide ideas on opportunities NNF-funded and other programs can take to further support diversity in the field of forestry; however, more research is needed. Study Implications Given the results of this pilot study, it is important to note that students of color who accept a graduate fellowship do so with goals of exploring a particular interest in the field of forestry. An assumption also exists that their degrees and experiences in certain graduate fellowship programs will yield long-term benefits, such as employment opportunities and high salaries. However, additional information would be helpful in strengthening the results of this study, which could include increasing the number of participants for more quantitative data or collecting qualitative data to gather additional details and information on the survey responses. }, journal={JOURNAL OF FORESTRY}, author={Arenas, Aaron A. and Spence, Porche L. and Nilon, Charles H. and Leggett, Zakiya H.}, year={2022}, month={Aug} } @article{gerald_deshazo_patterson_spence_2022, title={Growth and chemotaxis of nematodes reduced upon exposure to Third Fork Creek surface water}, volume={34}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85122954599&partnerID=MN8TOARS}, DOI={10.1186/s12302-021-00579-8}, abstractNote={AbstractBackgroundThird Fork Creek is a historically impaired urban stream that flows through the city of Durham, North Carolina.Caenorhabditis elegans(C. elegans) are non-parasitic, soil and aquatic dwelling nematodes that have been used frequently as a biological and ecotoxicity model. We hypothesize that exposure to Third Fork Creek surface water will inhibit the growth and chemotaxis ofC. elegans. Using our ring assay model, nematodes were enticed to cross the water samples to reach a bacterial food source which allowed observation of chemotaxis. The total number of nematodes found in the bacterial food source and the middle of the plate with the water source was recorded for 3 days.ResultsOur findings suggest a reduction in chemotaxis and growth on day three in nematodes exposed to Third Fork Creek water samples when compared to the control (pvalue < 0.05). These exploratory data provide meaningful insight to the quality of Third Fork Creek located near a Historically Black University.ConclusionsFurther studies are necessary to elucidate the concentrations of the water contaminants and implications for human health. The relevance of this study lies within the modelC.elegansthat has been used in a plethora of human diseases and exposure research but can be utilized as an environmental indicator of water quality impairment.}, number={1}, journal={Environmental Sciences Europe}, author={Gerald, C. and Deshazo, B. and Patterson, H. and Spence, P.}, year={2022} } @article{spence_phillips_mcallister_white_hollowell_2020, title={Student-scientist curriculum: Integrating inquiry-based research experiences and professional development activities into an introductory biology laboratory course}, volume={21}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85099381591&partnerID=MN8TOARS}, DOI={10.1128/JMBE.V21I3.2225}, abstractNote={ We designed a 16-week scaffolded student-scientist curriculum using inquiry-based research experiences integrated with professional development activities. This curriculum was implemented to teach undergraduate students enrolled in an introduction to biology course about enzyme activity, biochemical reactions, and alcohol fermentation. While working through the curriculum, students completed the entire scientific process by planning experiments, maintaining laboratory journals, analyzing and interpreting data, peer-reviewing research proposals, and producing and presenting a poster. The overall outcome was for students to complete a multiweek, collaborative, student-scientist project using Saccharomyces cerevisiae as the model organism. Student learning outcomes were evaluated using formative assessments (post-Research on the Integrated Science Curriculum survey and peer- and self-reflection worksheets) and summative assessments (pre/post assessments and assignment grades). Results indicated that more than 50% of the students scored 70% or higher on the collaborative student-scientist project, demonstrated several self-reported learning gains in scientific concepts and skills, and reported they would recommend this laboratory course to their peers. By providing the opportunity for students to carry out the entire scientific process, this curriculum enhanced their technical, analytical, and communication skills. }, number={3}, journal={Journal of Microbiology and Biology Education}, author={Spence, P.L. and Phillips, R.S. and McAllister, A.R. and White, S.L. and Hollowell, G.P.}, year={2020} } @article{spence_walker_robarge_preston_osmond_2015, title={Comparing nitrous oxide losses from three residential landscapes under different management schemes following natural rainfall events}, volume={18}, ISSN={["1573-1642"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84949200350&partnerID=MN8TOARS}, DOI={10.1007/s11252-015-0453-9}, number={4}, journal={URBAN ECOSYSTEMS}, author={Spence, Porche L. and Walker, John T. and Robarge, Wayne P. and Preston, Bill and Osmond, Deanna L.}, year={2015}, month={Dec}, pages={1227–1243} } @article{spence_floyd_howard_simmons_2015, title={Ecosystem Services and Environmental Health}, volume={9}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85066431537&partnerID=MN8TOARS}, DOI={10.4137/EHI.S38845}, abstractNote={Yet, in many developed and undeveloped parts of the world, consequences of these interrelated processes and the risks and hazards that they pose to both human health and ecosystems remain underexplored. This special issue of the Environmental Heath Insights will draw seek draw on new, empirical research which examines the nexus between ecosystem services and environmental health in the context of a rapidly changing world.}, journal={Environmental Health Insights}, author={Spence, P.L. and Floyd, M.F. and Howard, J. and Simmons, C.}, year={2015} } @article{spence_2015, title={Using Caffeine as a Water Quality Indicator in the Ambient Monitoring Program for Third Fork Creek Watershed, Durham, North Carolina}, volume={9}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85073238921&partnerID=MN8TOARS}, DOI={10.4137/EHI.S19588}, abstractNote={ Caffeine has been suggested as a chemical indicator for domestic wastewater in freshwater systems, although it is not included in water quality monitoring programs. The Third Fork Creek watershed in Durham, NC, is highly urbanized, with a history of receiving untreated wastewater from leaking and overflowing sanitary sewers. The poor water quality originating in the Third Fork Creek watershed threatens its intended uses and jeopardizes drinking water, aquatic life, and recreational activities provided by Jordan Lake. Organic waste contaminants have been detected in both Third Fork Creek watershed and Jordan Lake; however, the sampling periods were temporary, resulting in a few samples collected during nonstorm periods. It is recommended that (1) the concentration of caffeine and other organic waste contaminants are determined during storm and nonstorm periods and (2) caffeine is monitored regularly with traditional water quality indicators to evaluate the health of Third Fork Creek watershed. }, journal={Environmental Health Insights}, author={Spence, P.L.}, year={2015} } @article{spence_jordan_2013, title={Effects of nitrogen inputs on freshwater wetland ecosystem services - A Bayesian network analysis}, volume={124}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84877063290&partnerID=MN8TOARS}, DOI={10.1016/j.jenvman.2013.03.029}, abstractNote={Increased nitrogen (N) inputs to freshwater wetlands potentially affect the interaction between nitrous oxide (N2O) emissions and outflow water quality. The purpose of this study is to evaluate the influence of N inputs on N removal, as well as the interaction between N2O emissions and outflow water quality, using a Bayesian Belief Network (BBN). The BBN was developed by linking wetland classification, biogeochemical processes, and environmental factors. Empirical data for 34 freshwater wetlands were gathered from a comprehensive review of published peer-reviewed and gray literature. The BBN was implemented using 30 wetlands (88% of the case file) and evaluated using a single test file containing 4 wetlands (12% of the case file). The BBN implies it is not average annual total N load entering the wetland, but the N removal efficiency that influences the interactions between N2O emissions and outflow water quality. Even though the network has a very low error rate indicating a high predictive accuracy, additional testing and larger training and testing datasets would increase confidence in the model's ability to provide robust predictions and to reduce the uncertainty resulting from an incomplete dataset and knowledge gaps regarding the interactions between N2O emissions and outflow water quality.}, journal={Journal of Environmental Management}, author={Spence, P.L. and Jordan, S.J.}, year={2013}, pages={91–99} } @article{spence_osmond_childres_heitman_robarge_2012, title={Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events}, volume={48}, ISSN={1093-474X}, url={http://dx.doi.org/10.1111/j.1752-1688.2012.00658.x}, DOI={10.1111/j.1752-1688.2012.00658.x}, abstractNote={Spence, Porchè L., Deanna L. Osmond, Wesley Childres, Joshua L. Heitman, and Wayne P. Robarge, 2012. Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events. Journal of the American Water Resources Association (JAWRA) 48(5): 909‐924. DOI: 10.1111/j.1752‐1688.2012.00658.xAbstract:  A sampling system was used to evaluate the effect of residential lawn management on nutrient losses via overland flow generated during natural rainfall events from three residential landscapes: a high maintenance fescue lawn (HMFL), a low maintenance fescue lawn (LMFL), and a mixed forested residential landscape (FRL). A sampling system was located in designated areas within each landscape such that 100% of the runoff follows natural flow paths to the outlet ports and collects in sterile Nalgene® B3 media bags (Thermo Fisher Scientific, Rochester, NY). A rainfall event was defined as producing ≥2.54 mm of water. A total of 87 rainfall events occurred during a 20‐month monitoring period. The total runoff volume collected from the LMFL was higher than from the HMFL and FRL, but on average <1% of the total rainfall was collected from the three landscapes. Mean nitrate concentrations from each lawn did not exceed 0.6 mg N/l. Nutrient unit area losses from the HMFL, LMFL, and FRL were 1,000 times less than fertilizer and throughfall inputs, which were due to the presence of well‐structured soils (low bulk densities) with high infiltration rates. This study demonstrated that the frequency of runoff, total runoff volumes, and nutrient losses during natural rainfall events are lower from highly maintained (i.e., irrigation, fertilizer application, and reseeding) densely uniform manicured lawns than low maintenance lawns and forested residential landscapes.}, number={5}, journal={JAWRA Journal of the American Water Resources Association}, publisher={Wiley}, author={Spence, Porchè L. and Osmond, Deanna L. and Childres, Wesley and Heitman, Joshua L. and Robarge, Wayne P.}, year={2012}, month={May}, pages={909–924} } @article{walker_spence_kimbrough_robarge_2008, title={Inferential model estimates of ammonia dry deposition in the vicinity of a swine production facility}, volume={42}, ISSN={["1873-2844"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-41449099938&partnerID=MN8TOARS}, DOI={10.1016/j.atmosenv.2007.06.004}, abstractNote={This project investigates NH3 dry deposition around a commercial swine production facility in eastern North Carolina. Passive diffusion-tube samplers were used to measure weekly integrated NH3 concentrations at 22 locations along horizontal gradients from the barn/lagoon emissions complex (source) out to a distance of 700 m. A two-layer canopy compensation point model was used to predict bi-directional NH3 exchange within a 500 m circular buffer surrounding the source. The model takes into account differences in soil and vegetation emission potential, as well as canopy physical characteristics, among three primary surfaces surrounding the site: forest, crops spray fertilized with swine waste, and other fertilized crops. Between June 2003 and July 2005, mean observed NH3 concentrations ranged from 169.0 μg NH3 m−3 at a distance of 10 m from the source to 7.1 and 13.0 μg NH3 m−3 at 612 and 698 m in the predominant upwind and downwind directions, respectively. Median predicted dry deposition rates ranged from 145 kg NH3–N ha−1 yr−1 at 10 m from the source to 16 kg NH3–N ha−1 yr−1 at 500 m, which is ≈3.5× wet deposition of NH4+–N. Assuming a steady-state emission factor of 7.0 kg NH3 animal−1 yr−1 and a median population of 4900 animals, NH3 dry deposition over the nearest 500 m from the barn/lagoon complex accounted for 10.4% (3567 kg NH3) of annual emissions (34,300 kg NH3). A model sensitivity analysis shows that predicted deposition rates are more sensitive to assumptions regarding cuticular uptake relative to soil and vegetation emission potentials.}, number={14}, journal={ATMOSPHERIC ENVIRONMENT}, author={Walker, John and Spence, Porche' and Kimbrough, Sue and Robarge, Wayne}, year={2008}, month={Apr}, pages={3407–3418} } @article{stow_walker_cardoch_spence_geron_2005, title={N2O emissions from streams in the Neuse River watershed, North Carolina}, volume={39}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-25144433402&partnerID=MN8TOARS}, DOI={10.1021/es0500355}, abstractNote={We present N2O emission data from 11 sites in the Neuse River watershed. Emissions were measured using a static surface enclosure technique deployed on eight sites on the main river channel and three tributary sites. Ancillary data collected included dissolved oxygen, nitrate, total nitrogen, ammonium, dissolved organic carbon, total phosphorus, and temperature. Analysis using standard linear models, and classification and regression trees (CART), indicated nitrate to be the primary driving variable associated with N2O emission, although dissolved organic carbon concentration and water temperature were positively related with N2O emission as well. Relationships between nitrate concentration and N2O emission were consistent with those found in previous studies, although the data presented here represent the lower end of the range for both variables among published studies. Using our measured N2O emission rates along with literature values for the ratio of nitrogen gas to N2O produced during denitrification, we estimate N loss via denitrification in the Neuse River is approximately 17% of the annual N load delivered to the estuary.}, number={18}, journal={Environmental Science and Technology}, author={Stow, C.A. and Walker, J.T. and Cardoch, L. and Spence, P. and Geron, C.}, year={2005}, pages={6999–7004} }