Potomac Environmental Research and Education Center
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The mission of the Potomac Environmental Research and Education Center is to utilize the tools of scientific research, restoration, education, and policy analysis to help society understand and sustain natural processes in ecosystems, watersheds, and landscapes.
Research foci for the Center include:
- Restoration of the Potomac River and its Tributaries
- Sustainability of Natural Ecosystems in Suburban Areas
- Impact of Global Climate Change on Management of Aquatic Ecosystems
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Item Bioassessment of Nonpoint Source Impacts in Three Northern Virginia Watersheds(1994-07-13) Jones, R. Christian; Kelso, Donald P.Item Bioassessment of Prince William County Watersheds(1997-05-12) Jones, R. Christian; Kelso, Donald P.Item Fort Belvoir Aquatic Studies 1997(1999-03-19) Jones, R. Christian; Kelso, Donald P.Item Bioassessments of the Bull Run Watershed. 1998-99(2000-07-24) Jones, R. Christian; Arciszewski, JoannaItem Quantico Marine Corp. Base Stream Monitoring 1998-1999(2001-03-08) Kelso, Donald P.; Jones, R. Christian; Brittingham, Kevin D.; Maher, Amy M.; Morgan, Donald R.; Tuszynska, EmilyItem Bioassessment of Page Brook, Final Report(2002-01-14) Jones, R. Christian; Astin, LeAnne; Rowland, KathyItem Bioassessment of Roseville Run Watershed. Clarke Co., VA(2002-03-01) Jones, R. Christian; Astin, LeAnne; Rowland, KathyItem Bioassessment of Spout Run, Clarke County, VA(2002-08-30) Jones, R. Christian; Hansen, RyanItem Aquatic Survey of NASA Goddard Space Flight Center Main and East Campuses 2002(2003-12-05) Jones, R. ChristianItem An Ecological Study of Gunston Cove 2008(2009-12) Jones, R. Christian; Kraus, RichardItem An Ecological Study of Gunston Cove 2009(2010-12) Jones, R. Christian; Kraus, RichardItem The influence of past and future urbanization on watershed nitrogen export and hydrology dynamics in two mid-Atlantic watersheds in Fairfax, Virginia(2011-10-21) Albert, RyanThis study examines urban land use change and its impact on watershed hydrology and nutrient loading in the Accotink and Pohick watersheds in Fairfax County, Virginia. The dissertation explored the amount of urbanization in the watersheds over the past 30 years and the impact of that urbanization on nitrogen loadings and stream hydrology. Further, it examined different projections of future urban development in the watersheds and how urbanization may affect nitrogen loadings and hydrologic changes. It was hypothesized that deterioration in hydrologic conditions and increases nitrogen loadings would be notable. Land use was estimated from 1975 to 2004 using a combination of remote sensing and demographic data, which was given the name of the Household Method. Adjusted land use projections from an existing study generated by the SLEUTH model and projections using the household method were used to estimate future land use. These land use estimates were input into several analytical tools, including the hydrologic component of HSPF, L-THIA, and export coefficient-based approaches. Water quality data collected by George Mason University and the Norman M. Cole Jr. Pollution Control Plant are available at four sites from 1984-1992. Data were also collected on 24 occasions in 2005 at four sites in the watersheds as part of this dissertation. Nitrate-N, ammonia-N, total phosphorus and soluble reactive phosphorus were compared between watersheds using statistical techniques and a multiple regression loading model (LOADEST); focus was given to nitrogen. Physical parameters, including conductivity, dissolved oxygen, pH, and temperature were also analyzed. Modeled and observed results indicate that significant changes correlated with increased urbanization have occurred to the hydrology of these watersheds. Furthermore, without implementation of effective Best Management Practices (BMPs), significant alterations in hydrology will continue into the future. Nitrogen loadings have also increased and will likely continue to increase without effective BMPs, although the increases in nitrogen loading do not pose a significant a risk to the streams themselves. However, these increased nitrogen loadings may pose a potential risk to the Chesapeake Bay ecosystem.Item An Ecological Study of Gunston Cove 2010(2011-12-13) Jones, R. Christian; Kraus, RichardItem An Ecological Study of Gunston Cove - 2011(2012-11-27) Jones, R. Christian; de Mutsert, KimItem Diel and seasonal patterns in water quality continuously monitored at a fixed site on the tidal freshwater Potomac River(Freshwater Biological Association, 2013) Jones, R. Christian; Graziano, Alexander P.Recent advances in water quality monitoring have facilitated the acquisition of temporally rich datasets that allow comprehensive analysis of patterns and underlying processes and drivers at multiple scales. We analyzed data from a continuous water quality monitor on the tidal Occoquan River, a tributary of the tidal Potomac River and Chesapeake Bay. Temperature, conductivity, dissolved oxygen (DO), and pH were collected at 15 minute intervals from April through early November of 2010. Results of time series analysis indicate that, on a short-term basis, conductivity manifested an underlying semidiel pattern, presumably driven by tidal excursion. In comparison, DO, pH, and temperature exhibited a diel pattern correlated with the daily light and temperature cycle. Longer-term patterns were related to longer-term climatic factors such as a dry summer with low freshwater inputs, seasonal progressions of light and temperature, and a river discharge spike in early October. Examination of multiday patterns in DO and pH using 15 minute data during a climatically stable period illustrated both diel and semidiel patterns. Patterns in a period of strong hydrological forcing revealed a disruption of diel and semidiel patterns for several days with a general restoration of patterns thereafter. Both diel and seasonal data suggest that abundant submerged aquatic vegetation in the study area was the main primary producer component driving diel and seasonal DO and pH patterns.Item Seasonal Patterns of Stratification, Nutrient Concentrations, and Chlorophyll in a Shallow Mid-Atlantic Pond(2013-08-02) Wheat, ShannonItem Seasonal Patterns of Stratification, Nutrient Concentrations, and Chlorophyll in a Shallow Mid-Atlantic Pond(2013-08-02) Wheat, ShannonItem Relationships among Escherichia coli (E. coli), Total Suspended Solids and Flow for Three Northern Virginia Subwatersheds: Rabbit Branch, Upper Accotink Creek, and Daniels Run(2013-10-02) Washington, MarissaThis project was designed and completed to satisfy the requirements for the M.S. Program in Environmental Science and Policy at George Mason University. Three sites located in Fairfax, Virginia residential areas were chosen to monitor Escherichia coli concentrations between May 18th and July 19th, 2013 and to examine the relationship of E. coli to stream flow, total suspended solids (TSS) and impervious cover. Each site was visited a total of 9 times during the study period. Analysis of data from these sites indicated that they are not meeting the Virginia Department of Environmental Quality (VDEQ) standard of 235 CFU/100 mL for E. coli in recreation streams. The range for E. coli over all three sites was 78 - 19,100 CFU/100 mL. There were also nine samples in which the levels were above the range of the test procedure (>20,000 CFU). This study also suggested that E. coli may respond to increased impervious cover, TSS and rainfall; however, due to a high degree of variability most of the relationships were not significant. Visual examination of the watersheds indicate that there are multiple potential upstream non-point sources including human and animal activity that could contribute to elevated E. coli levels. Because these sites are in violation of state water quality standards, it is imperative that the County and City Storm Water Planning Divisions further investigate and devise plans to fulfill the purpose of the Clean Water Act. Two of the three sites, Daniels Run and Rabbit Branch, could benefit from projects that have been proposed.