The Virginia Runoff Reduction Method (RRM) was adopted in 2014 as a compliance tool for evaluation of stormwater volume and quality, and necessitates use of urban stormwater best management practices (BMPs) to meet regulatory standards. Coastal Virginia is characterized by flat terrain, shallow water tables, and low permeable soils that may limit the application of BMPs as recommended by state regulations. Soil morphological features are often used to estimate the seasonal high water table (SHWT) for initial feasibility, but existing soil data misrepresented expected SHWT depths in the Virginia Beach, VA, study area. A GIS-based methodology relying on perennial surface water elevations and USGS groundwater monitoring data was developed to estimate the SHWT depth in Virginia Beach. The SHWT map was shown to be consistently more reliable than available predictions based on soil morphology, and was used as input to a BMP siting tool. The tool, known as BMP Checker, was developed to explore how flat terrain, shallow water tables, and poor soils influence BMP siting in coastal Virginia. The BMP Checker algorithm was validated on 11 Virginia Beach sites before application on 10,000 ft2 (929 m2) area sections across the city. Citywide application showed that the most widely applicable BMPs in the study area include wet ponds that intercept groundwater and constructed wetlands. Conversely, sheet flow to conservation area and infiltration practices are the least applicable. Because the RRM assigns more credit to infiltration-based practices, sites in Virginia Beach may find it difficult to meet regulatory standards. / Master of Science

Local communities and regional networks are currently exploring the strategy of developing local and regional food systems in order to enhance food security. The relationship between food consumption and production must be tested at various scales and across geographies in order to describe how place-based diets influence agricultural land use and the degree to which a discrete agricultural land base can feed a population. This thesis used two models to integrate data from across the agricultural and nutritional sciences to test the capacity of regional food systems to meet complete diet food need in the south-central Appalachian foodshed. First, a complete diet approach was applied to the entire foodshed to test the influence of animal product and fat consumption on the land requirements of food production. The quantity of specific regionally-adapted food commodities for six diet patterns were estimated following USDA recommendations and compared to county-based Census of Agriculture land use data to determine agricultural carrying capacity. Second, a sub-regional geospatial foodshed model used site-specific soil and current land cover datasets to estimate the spatial distribution of food production capacity relative to the per capita food needs determined by the complete diet model. Together, these studies contribute information from a data-user perspective for stakeholders and planners interested in quantifying the capacity of regional food systems to meet total food needs. / Master of Science

Floodplain inundation often provides water quality benefits by trapping sediment and biogeochemically transforming other pollutants. Hydrologic floodplain connectivity is a measure of water exchanges and interactions between the main channel and the floodplain via surface (inundation) and subsurface (groundwater) connections. Using an automated model combining GIS and numerical analysis software, this study examined floodplain inundation patterns and measured floodplain connectivity for the Mahantango Creek watershed (Pennsylvania, USA). Connectivity was quantified by developing a metric that included inundation area and duration. Long-term hydrographs at each reach in the watershed were developed via QPPQ (Flow-Percentile-Percentile-Flow) methodology using regional regression analysis to calculate the ungauged flow duration curves (FDC). Inundation area (normalized to stream length) was found to increase with drainage area, suggesting larger streams have more area available for biogeochemical activity. Annual connectivity increased with drainage area, suggesting larger streams, having higher connectivity, should be the focus of individual reach restoration projects due to higher potential for water quality benefits. Across the watershed as a whole, however, the total annual connectivity across first order streams was greater than higher order streams, suggesting the collection of small streams in a watershed may have a stronger effect on outlet water quality. Connectivity was consistently higher during the non-growing season, which was attributed to higher flows. Despite higher connectivity during the non-growing season, increased floodplain biological activity may be negated by low temperatures, reducing microbial activity. Correlations between land use and connectivity were also found, emphasizing dynamics between flow, channel morphology, and floodplain inundation. / Master of Science

Conservation strategies frequently require prioritization of targets due to limited budgets and personnel. Prioritization involves choosing those areas that return the most conservation value for the time and money invested. Hence, the process of prioritization involves evaluating multiple conservation values and the uneven spatial distribution of those values across a landscape of concern. The goal of this study was to help conservation organizations improve decision making for implementation of prioritization-based strategies for land protection using a GIS-based, multi-criteria decision support system (GIS-MCDS). Geographic Information Systems (GIS) can assist conservation planners in quantifying the relative desirability of one area over another, therefore enabling better business and ecological decisions. GIS analyses for planning are routinely undertaken over large geographic extents such as ecoregions to identify priority areas. These analyses often summarize priority by pixel values in a raster image. Implementation of conservation strategy often takes place at the much larger parcel level. Therefore, aggregating pixel-based results by parcels is a prerequisite to implementation of a purchase or easement strategy. I developed a spatial decision support system in an attempt to quantify private land holdings in the High Knob area of Virginia for their relative conservation value, as defined by the Clinch Valley Program of The Nature Conservancy. It utilizes a proxy approach for measuring conservation values and an analytical hierarchy process to aggregate the results by privately held real estate parcels. Simple prioritizations are often based on parcel size alone, rather than consideration of the many conservation values that characterize land parcels. Though it is much quicker and easier to prioritize parcels in this manner, such simplicity risks missing important smaller areas for conservation while prioritizing larger parcels with less value. I compared this simple "bigger is better" ranking method to the GIS-based multi-criteria method developed for TNC. There was a 0.57 correlation between the ranked lists produced by the two models, suggesting that parcel size alone does partially explain the complexity modeled by the multi-criteria method. However, the more complex method did produce different top priority parcels, which could significantly change an organization's implementation strategy. I conclude that both methods have their applications, though the multi-criteria method is better for long-term implementations of strategic acquisition and easement. A secondary goal was to identify to what extent land trust organizations are prepared to implement a multi-criteria type analysis like the one considered in this study. I conducted an online survey of conservation professionals on how their organization currently uses GIS and their satisfaction with GIS analyses to meet their organizational mission. Sixty-one responses were collected and analyzed. The overwhelming majority of conservation organizations recognize the benefits that GIS bring and have already developed some level of internal expertise, though many barriers to using GIS were also identified. From these results, I conclude that most land trust conservation organizations are not currently utilizing the insights that multi-criteria GIS prioritization is capable of offering, but that their previous positive experience with GIS makes such analyses an attractive proposition for those on the cutting edge of the land conservation movement. / Master of Science

In 1997, a phytoremediation program began at a creosote-contaminated former railroad tie yard in Oneida, Tennessee with the planting of over 1000 hybrid poplar trees onsite. Creosote, a mixture of hazardous chemicals composed of 85% polycyclic aromatic hydrocarbons (PAH) had entered the site soil and ground water. After planting, a seasonal ground water testing program began that monitored the progress of remediation by measuring the concentration of the 10 predominant PAHs in the contaminant plume: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, and benzo(b)fluoranthene. The concentrations of these compounds steadily decreased over time, but the role the trees played in the remediation was unclear. In order to gain a clearer understanding of the role the trees played in contaminant remediation, chemical analysis of tree tissue began. It was not known whether the trees were taking up PAH contaminants or their metabolites or if the rhizosphere zone created by the trees simply enhanced the ability of the site microflora to degrade the PAH. The objectives of this research were to (1) develop a suitable method for the chemical analysis of tree tissue collected from a field site, (2) determine if there were any chemicals not usually found in poplar trees that occurred in the trees growing over contamination, (3) determine if bud, bark, and twig tissue differed in their ability to predict ground water contamination, and (4) determine if a spatial correlation existed between the aromatic compounds in the tree tissue and the ground water total PAH plume. Two types of tree tissue/ground water comparisons were performed: spatial distribution of isoeugenol concentration in tree tissue with spatial distribution of total PAH in ground water over the area of interest; and the spatial distribution of the quantity of aromatic compounds in tree tissue with the spatial distribution of total PAH concentration in ground water. Due to unit discrepancies between the quantities of interest, all comparisons were made on a percentile basis. Initial tree sampling revealed that several compounds not usually present in poplar trees occurred only in those trees growing over contamination. In the first part of this study, the concentration of one of these chemicals, the substituted phenol isoeugenol, was compared with the concentration of total PAH in ground water from samples collected from February-March 2002. The bark tissue percentiles fell within 20 percentiles of ground water total PAH concentrations in 60% of the study area. The twig tissue showed slightly better agreement, with 67% of the study area differing from ground water by twenty percentiles or less. The second comparison took place over three sampling events: March 2001, July 2001, and February-March 2002. The number of unique aromatic compounds in bark, bud, and twig tissue was compared with the total PAH concentration in ground water. Twig tissue aromatic compound content was the most accurate predictor of ground water contamination among the tissue types. After excluding those chemicals likely to be interferences from consideration, twig tissue aromatic content agreed with ground water total PAH concentration to within 20 percentiles over 2/3 or more of the study area during each sampling event, suggesting the potential uptake of PAHs or their microbial metabolites as a mechanism of phytoremediation at the site. / Master of Science

A watershed scale water quality evaluation system was developed for assessing spatial variation of subsurface pesticide movement. The system consists of a linked-transport model component for performing simulation and a GIS component for processing spatially-related data. The surface heterogeneity caused by agricultural activities, topographic, hydrologic, and soil type variations in a watershed was handled by partitioning the watershed into homogeneous subfields. The subsurface soil profile and aquifer heterogeneities were considered by dividing the subsurface domain into root zone, intermediate vadose zone, and saturated zone, respectively. On each of the homogeneous subfields, the physically-based models, PRZM and VADOFT, were linked to simulate pesticide transport in the root and intermediated vadose zones. Pesticide movement in groundwater underneath the watershed was simulated by linking the other two models with SUTRA. An irregular shape finite element mesh generator was developed for fitting the irregular shape watershed boundary and reducing the number of nodes of the finite element mesh. Either transient or steady state flow and transport simulation could be performed with the system. The system is able quantitatively to produce detailed spatial variation maps of pesticide concentrations at any desired depth in the unsaturated zone and in groundwater. The system requires spatially-distributed information as inputs. Management of large volumes of spatially-referenced data which represent the heterogeneous properties of the watershed were facilitated by a developed GIS component. The GIS data processing component was composed of spatial data manipulation and display, attribute database management, and model input information extraction subcomponents. The spatial data processing component consists of data format conversion, map registering, map editing, new information generation, and map display subcomponents. / Ph. D.

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This research focused on adventure tourism in KZN. The adventurer traveller is interested in remote pristine hotspots. A concern is that irresponsible behaviour on the adventurer’s part could lead to the destruction of the fragile natural environment, as well as negatively interfere with the local traditional cultural values. Adventure hotspots were identified by using the functionalities of a GIS. These findings were validated by tourism practitioners in KZN. The researcher also proposed a practical solution that could improve or enhance the behaviour of adventurers. Existing media were collated into information prompts. These information prompts were categorised in tables that could be linked to a mobile GIS environment. The researcher then examined the framework requirements for a mobile GIS. This resulted in a set of seven criteria that brought together the core essentials required for the conceptual framework of a mobile GIS device dedicated to the adventurer in KZN. / Geography / M.A. (Geography)

Rapid Bioassessment Protocols integrate a suite of community, population, and functional metrics, determined from the collection of benthic macroinvertebrates or fish, into a single assessment. This study was conducted in Dallas County Texas, an area located in the blackland prairie eco-region that is semi-arid and densely populated. The objectives of this research were to identify reference streams and propose a set of metrics that are best able to discriminate between differences in community structure due to natural variability from those caused by changes in water quality due to watershed impacts. Using geographic information systems, a total of nine watersheds, each representing a different mix of land uses, were chosen for evaluation. A total of 30 metrics commonly used in RBP protocols were calculated. Efficacy of these metrics to distinguish change was determined using several statistical techniques. Ten metrics were used to classify study area watersheds according to stream quality. Many trends, such as taxa presence along habitat quality gradients, were observed. These gradients coincided with expected responses of stream communities to landscape and habitat variables.