The Chesapeake Bay states continue to struggle to achieve the water quality goals set out in the Chesapeake Bay Agreement. While policy efforts to combat eutrophication tend to focus on reducing nutrient loads at point and nonpoint sources, waters of the Bay can be improved through an increase in the assimilative capacity of the ecosystem, which would remove nutrients (called nutrient assimilation services) from ambient waters. The filtering capacity of the native oyster, C.virginica, is a widely recognized means to enhance water quality. With an increase in the number of oysters in the Bay, and no decrease in wild stocks, oyster aquaculture has the potential to also increase the nutrient assimilation capacity of the ambient environment. Yet the expansion of commercial aquaculture in the Bay has been limited by financial constraints. Increased water quality services might be forthcoming if oyster aquaculturists received financial compensation for the nutrient removal services they provide. Based on previous research, this study develops a procedure for estimating annual nutrient removal from a given size oyster aquaculture facility. Next, a firm level bio-economic simulation model was constructed to estimate the amount of compensation needed by a commercial oyster aquaculture firm to make a new investment in oyster aquaculture. The amount of compensation needed is interpreted as the cost of providing nutrient removal by oyster aquaculture. Results indicate that under many circumstances, nutrient removal services can be provided by oyster aquaculture facilities at a per unit cost comparable with some non-point and point source nutrient removal technologies. Finally, a select number of funding resources were identified as potential outlets for creating payments and demand for nutrient assimilation services. / Master of Science

Sherwood Lake, a 165 acre public fishing impoundment in Greenbrier County, West Virginia, was treated with calcium carbonate for four years. The limestone treatment was done by revolving limestone drums installed above the lake on Meadow Creek. The limestone drum provided continuous treatment throughout the period. Limnological conditions of Meadow Creek and Sherwood Lake were monitored throughout the treatment period. Physicochemical and plankton data were collected monthly and the fish population sampled annually. The water quality of Sherwood Lake improved gradually during treatment, however, by the end of 1968 the lake could only be classified as a soft water lake. The growth of Elodea was encouraged by the addition of limestone. A lack of available nutrients and decreased productivity at higher trophic levels was attributed to the dense growths of Elodea. The mean annual volume of plankton decreased during lime treatment, however, this decrease was attributed to the usurping of available nutrients by higher aquatic plants. Low concentrations of available phosphorus was considered to be the major chemical factor limiting biological production. No significant growth increments were evident for any species of fish of any age that could be attributed directly to the limestone treatment of Sherwood Lake. An increase in the standing crop of fish was noted but could not be ascribed entirely to the addition of limestone. / Master of Science

Anthropogenic salinization of freshwater is a global concern. In freshwater environments, elevated levels of major ions, measured as total dissolved solids (TDS) or specific conductance (SC), can cause adverse effects on aquatic ecosystem structure and function. In central Appalachia, eastern USA, studies largely rely on Rapid Bioassessment Protocols with semi-quantitative sampling to characterize benthic macroinvertebrate community response to increased salinity caused by surface coal mining. These protocols require subsampling procedures and identification of fixed numbers of individuals regardless of organism density, limiting measures of community structure. Quantitative sampling involves enumeration of all individuals collected within a defined area and typically includes larger sample sizes relative to semi-quantitative sampling, allowing expanded characterization of the benthic community. Working in central Appalachia, I evaluated quantitative and semi-quantitative methods for bioassessments in headwater streams salinized by coal mining during two time periods. I compared the two sampling methods for capability to detect SC-induced changes in the macroinvertebrate community. Quantitative sampling consistently produced higher estimates of taxonomic richness than corresponding semi-quantitative samples, and differences between sampling methods were found for community composition, functional feeding group, dominance, tolerance, and habit metrics. Quantitative methods were generally stronger predictors of benthic community-metric responses to SC and were more sensitive for detecting SC-induced changes in the macroinvertebrate community. Quantitative methods are advantageous compared to semi-quantitative sampling methods when characterizing benthic macroinvertebrate community structure because they provide more complete estimates of taxonomic richness and diversity and produce metrics that are stronger predictors of community response to elevated SC. / Master of Science / Surface coal mining in central Appalachia, eastern USA, contributes to increased salinity of surface waters, causing adverse effects on water quality and aquatic life. Stream condition is often evaluated through sampling of benthic macroinvertebrates because they are ubiquitous in aquatic environments and differ in sensitivity to various types of pollution and environmental stressors. In central Appalachia, studies have largely relied on semi-quantitative sampling methods to characterize effects of elevated salinity on benthic macroinvertebrate communities in headwater streams. These methods are ‘semiquantitative’ because processing of samples requires subsampling procedures and identification of a fixed number of individuals, regardless of the number of organisms that were originally collected. In contrast, quantitative sampling involves identification and counting of all collected individuals, often resulting in organism counts that are much higher than those of semi-quantitative samples. Quantitative samples are typically more time-consuming and expensive to process but allow for expanded description of the benthic macroinvertebrate community and characterization of community-wide response to an environmental stressor such as elevated salinity. Working in central Appalachian streams, I compared 1) depictions of benthic macroinvertebrate community structure; 2) benthic community response to elevated salinity; and 3) the minimum levels of salinity associated with community change between quantitative and semi-quantitative methods. Quantitative sampling methods provide many advantages over semi-quantitative methods by providing more complete enumerations of the taxa present, thus enhancing the ability to evaluate aquatic-life condition and to characterize overall benthic macroinvertebrate community response to elevated salinity caused by surface coal mining.

Quantification of total phosphorus (TP) loads entering a lake or reservoir is important because phosphorus is most often the limiting nutrient in terms of algae growth, thus phosphorus can control the extent of eutrophication. Four methods for assessing the annual tributary phosphorus loads to two different Virginia reservoirs were analyzed, three methods that use tributary monitoring program data and one that uses land-use and rainfall data. In this project, one tributary has been extensively monitored for many years and served as a control on which the other methods were tested. The key difference between this research and previous studies is the inclusion of flow-weighted composite storm sampling instead of simple grab sample analyses of storm flow. Three of the methods employed flow stratification, and the impact of the base flow separation point was examined. It was found that the Regression Method developed in this research was the least sensitive to the base flow separation point, which is a valuable attribute because a wrong choice will not significantly affect the estimate. The Monte Carlo Method was found to underestimate the TP loads. The amount of rainfall impacted the accuracy of the methods, with more error occurring in a year with lower precipitation. / Master of Science

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This study examines farm-level financial costs and environmental benefits from three alternative manure management policies, incorporating all manure (INCORP), limit nitrogen applications to agronomic recommendations (NLIMIT), and phosphorus applications limited to crop removals (PLIMIT), on representative 60, 100, and 150-cow dairy and dairy/poultry farms. Current nutrient applications are manure-based, with each farm substituting poultry litter for commercial fertilizer. Potential field-level nutrient losses estimated by EPIC, a soil/plant growth simulation model, indicate the highest nitrogen losses on grass hay and pasture and the highest phosphorus losses on no-till com. The highest nutrient applications and nutrient losses occur on the 60 and 100-cow dairy/poultry farms. INCORP is ineffective at significantly lowering nutrient losses. NLIMIT reduces nitrogen losses by 30% and phosphorus losses by 6%. PLIMIT is the most effective policy, lowering both nitrogen and phosphorus losses over 34%. The largest farm-level reduction in nutrient losses is on the 60-cow dairy/poultry farm. Ryelage was the only crop yield that varies under the alternative policies. Financial simulation with FLIPSIM indicates that INCORP and NLIMIT do not affect farm financial performance. PLIMIT reduces farm net cash income and ending net worth as farms substitute commercial fertilizer for poultry litter. PLIMIT does not cause dairy farms to go out of business but does significantly reduce their cash available for family living expenses below minimum requirements. Dairy/poultry farms maintain adequate cash incomes under PLIMIT. PLIMIT lowers net cash income on all county dairy and dairy/poultry farms by 8% to 16% under litter disposal costs of $10 to $40 per ton. The smaller land-intensive 60-cow dairy/poultry farm has the largest decrease in cash income while the smallest decrease is on the 150-cow dairy/poultry farm. The 100 and 150-cow dairy/poultry farms maintain higher ending net worth than corresponding size dairy farms at disposal costs of $40 per ton. County net cash farm income declines by $2.57 to $5.16 per pound of reduced nitrogen losses and $15.68 to $31.44 per pound of reduced phosphorus losses. The study indicates that NLIMIT reduces nitrogen losses without affecting farm incomes whereas reducing both nitrogen and phosphorus losses under PLIMIT substantially reduces farm income. Nutrient management plans need to be directed at smaller land-intensive farms to achieve substantial nutrient loss reductions. / Ph. D.

Surface coal-mining is a source of selenium (Se) contamination in streams of the Appalachian coalfields. Selenium dynamics in aquatic systems are complex and largely controlled by site-specific factors, but have been understudied in Appalachian headwater streams. In this study, we evaluated the degree and dynamics of Se enrichment and bioaccumulation in headwater streams influenced by coal-mining. Based on Se concentrations in macroinvertebrates collected from 23 headwater streams, nine sites were selected for further study: three reference streams with no history of coal-mining, and six streams influenced by coal mining. Mining-influenced streams were further separated into high-Se and low-Sestreams based on macroinvertebrate tissue Se concentrations. Water-column, sediment, biofilm, leaf detritus, and prey and predator macroinvertebrates were collected and analyzed for Se concentration during two sample periods, Sept. - Oct. 2015 and Feb.-March 2016. Selenium concentrations in all media were found to be elevated in mining-influenced over reference streams and in high-Se over low-Se streams. Selenium dynamics, enrichment in particulate media (sediment, biofilm and leaf detritus) and trophic transfer of Se to prey from particulate media and to predators from prey, did not exhibit major differences among streams of differing Se levels. Water column Se concentrations were predicative of Se concentrations in macroinvertebrate tissues. Findings from this study indicate headwater streams influenced by coal-mining are capable of a high degree of Se bioaccumulation in macroinvertebrate populations. / Master of Science / Surface coal-mining is a source of selenium (Se) contamination in streams of the Appalachian coalfields. Selenium dynamics in aquatic systems are complex and largely controlled by sitespecific factors, but have been understudied in Appalachian headwater streams. In this study, we evaluated the degree and dynamics of Se enrichment and bioaccumulation in headwater streams influenced by coal-mining. Based on Se concentrations in macroinvertebrates collected from 23 headwater streams, nine sites were selected for further study: three reference streams with no history of coal-mining, and six streams influenced by coal mining. Mining-influenced streams were further separated into “high-Se” and “low-Se” streams based on macroinvertebrate tissue Se concentrations. Water-column, sediment, biofilm, leaf detritus, and prey and predator macroinvertebrates were collected and analyzed for Se concentration during two sample periods, Sept. - Oct. 2015 and Feb.- March 2016. Selenium concentrations in all media were found to be elevated in mining-influenced over reference streams and in high-Se over low-Se streams. Selenium dynamics, enrichment in particulate media (sediment, biofilm and leaf detritus) and trophic transfer of Se to prey from particulate media and to predators from prey, did not exhibit major differences among streams of differing Se levels. Water column Se concentrations were predicative of Se concentrations in macroinvertebrate tissues. Findings from this study indicate headwater streams influenced by coal-mining are capable of a high degree of Se bioaccumulation in macroinvertebrate populations.