Shore Of Virginia Research Articles

The Effect of Salt Marsh on Residential Property Values

Salt marshes provide a myriad of critical ecosystem services yet have been threatened by urban expansion, sea level rise, and the armoring of coastal property. This study uses a hedonic property price method to evaluate the effects of salt marshes on residential property values in the Eastern Shore of Virginia. Contrary to findings from the wetland literature, results show an insignificant relationship between proximity to salt marsh and residential property values. In contrast, results show a statistically significant increase in property values with increasing proportions of salt marsh within 250 to 500 meters of the parcel. Furthermore, the increase in value is found to be larger for proportions of preserved relative to non-preserved salt marsh in this proximity of the home. The findings of this study can contribute to understanding the spatial patterns for housing premiums stemming from salt marshes. The information can be used to guide coastal management agencies on how to conserve salt marshes in a way that promotes residential property values.

Do Macroalgal Mats Impact Microphytobenthos on Mudflats? Evidence from a Meta-Analysis, Comparative Survey, and Large-Scale Manipulation

Eutrophication and species introductions have resulted in increased macroalgal biomass in coastal ecosystems around the globe. Macroalgal mats may compete with microphytobenthos (MPB) for light and nutrients and, due to their position in the canopy, have a negative impact on MPB biomass. We tested this effect by conducting a meta-analysis of prior experiments, as well as a comparative survey, and a macroalgal-removal manipulation in the coastal lagoons of the Virginia Coastal Reserve (VCR) on the eastern shore of Virginia (USA). In all cases, MPB biomass was estimated using benthic chlorophyll as a proxy. While prior individual studies documented impacts of macroalgae, when effect sizes were averaged across studies, there was no consistent effect of macroalgal biomass on MPB biomass. In the VCR, a non-native red macroalga, Gracilaria vermiculophylla, dominates intertidal mats and attains high biomasses at some sites. Nevertheless, MPB biomass was unrelated to macroalgal mass based on a survey of mudflats. Further, when macroalgae were experimentally manipulated on a mudflat using a before and after impact design, there was no change in MPB. Based on the meta-analysis, survey, and manipulation we conducted, macroalgal mats do not have a generalizable effect on MPB, interactions seem context-dependent, and in the VCR, the effects on MPB appear neutral. This finding is important given the significance of MPB in supporting food webs and other estuarine ecosystem functions, as well as the increasing frequency and intensity of macroalgal blooms.

Draft Genome Sequences of Two Salmonella Strains Isolated from Wild Animals on the Eastern Shore of Virginia.

ABSTRACTAntimicrobial-resistant (AMR) Salmonella infections pose a significant public health threat. Here, we announce two draft genomes of Salmonella strains isolated from wildlife harboring an alarming array of antibiotic resistance genes. Continued investigations of these genomes will provide insight into the possible attribution of AMR Salmonella infection of wild animals.

Impacts of Invasive Phragmites australis on Diamondback Terrapin Nesting in Chesapeake Bay

The range expansion of exotic plant species, including the invasive reed Phragmites australis, causes widespread structural and functional changes to coastal ecosystems along the Atlantic and Gulf Coasts of North America. Native estuarine species, such as the diamondback terrapin (Malaclemys terrapin), are at risk of adverse effects from rapid habitat changes due to exotic invasions. Diamondback terrapins currently face population threats including by-catch mortality in crab pots, predation, and habitat loss, and populations may continue to suffer if deleterious plant invasions into preferred nesting habitats are left unchecked. We examined the extent to which Phragmites affects nesting of a breeding population of diamondback terrapins at Fisherman Island National Wildlife Refuge on the eastern shore of Virginia, where Phragmites has recently expanded into known areas of terrapin nesting. With data collected from the 2015 nesting season, we quantified the extent to which Phragmites shading could impact nest incubation temperature and determined how Phragmites density impacts the risk of rhizome invasion into nests. We conclude that Phragmites cover greater than 50% would decrease incubation temperatures of terrapin nests sufficiently to produce predominantly male hatchlings. Phragmites cover had no observed effect on root growth into simulated nests, but cover by other dune plant species explained observed trends in root growth. These results suggest that terrapins may be negatively impacted by Phragmites expansion into open nesting sites. Breeding site fidelity exhibited by terrapins and other estuarine species could limit the ability of their populations to adjust to rapid coastal expansion of invasive plant species.

Stakeholder Engagement and Survey Tools for Oil Spill Response Options

ABSTRACT Oil spill stakeholders, including decision makers and other groups, have expressed concerns about and questioned the use of dispersants and other non-mechanical response options for years. Concerns in past decades were primarily ecological, but during the Deepwater Horizon oil spill some individuals and communities in the Gulf of Mexico states also articulated perceptions of public health risks associated with the use of dispersants. Effective risk communication is essential to manage the potential risks associated with oil spills. Stakeholders concerned about risks want or need information in the form of communications products, such as guides or briefs. Because people process new information within the context of their existing beliefs, such communication products are likely to be more effective and useful for their intended audiences if they are designed to: (1) take into account the communication recipients' existing beliefs; and (2) directly address the decisions/judgments faced by recipients by providing them with the information they want and need to make those decisions. Stakeholder engagement is essential to learn about risk perceptions, to learn about what information stakeholders want and need to make decisions effectively, and to develop communication products to that end. This paper builds upon a mental models approach to dispersant risk communications research from the 1990s. It describes and presents results from an industry-government collaborative project to develop risk-based tools designed to communicate the subject of dispersants to local level stakeholders among others. This project includes an expanded science-informed dispersant decision model, two stakeholder open houses, and two surveys (interactive and online) to gather data-driven insights about local stakeholder knowledge and understanding of dispersants, as well as their perceptions of the risks and benefits associated with dispersant use during a spill in relation to other response options. The surveys were distributed at two open houses for local stakeholders on the Eastern Shore of Virginia (Wallops Is.) and the Pacific Northwest (Port Townsend, WA). Both open houses were co-sponsored with USCG-led Area Committees. The Virginia workshop was also co-sponsored by The Nature Conservancy and the Virginia Shore Keeper. It is expected that the surveys may be incorporated into future meetings and open houses involving stakeholders at any level, e.g., local, state, regional or national. The data from the surveys can guide the improvement of future communication efforts about dispersants, as well as provide support for enhanced stakeholder engagement during preparedness and response.

Marriage on the Margins: Free Wives, Enslaved Husbands, and the Law in Early Virginia

In 1725, Jane Webb, a free woman of color, sued Thomas Savage, a slave owner and middling planter, in Northampton County Court, on the Eastern Shore of Virginia. Webb v. Savage was an unusual lawsuit, the culmination of over twenty years of legal wrangling between two parties who had an uncommon and intimate connection. The case originated in a 1703 contract between the pair, and at the time it was written, its terms, assumedly, were clear and mutually agreed upon. Two decades later, however, a tangled skein of circumstances obscured the stipulations of that original agreement. Over the course of those same years, the legal meaning of freedom for individuals like Jane Webb had fundamentally changed. Both fraught interpersonal relations and the evolution of race-based law mattered to the 1725 chancery case for one simple reason: Thomas Savage owned Jane Webb's husband. Despite the fact that Webb's spouse, named only in the records as Left, was enslaved, their marriage was legally recognized, and the seven children born to the couple, following the legal doctrine partus sequitur ventrum, took their free status as well as their surname from their mother.

Spectral definition of the macro-algae Ulva curvata in the back-barrier bays of the Eastern Shore of Virginia, USA

We have developed methods to determine the visible (VIS) to near-infrared (NIR) spectral properties of thalli and epiphytes of bloom-forming and green macrophyte Ulva curvata in back-barrier lagoons in Virginia, USA. A 2% increase in NIR thalli reflectance from winter to summer (ca. 9.5%) matched the drop in summer NIR transmittance (ca. 90%). In contrast, summer and winter VIS reflectance (reaching 6%) were nearly identical while winter transmittance (ca. 85%) was 10–20% higher. NIR absorption remained at 5% but VIS absorption increased by 10–20% from winter to summer. Replicate consistency substantiated the high transmittance difference indicating thallus composition changed from summer to winter. Epiphytes increased thallus reflectance (<ca. 4%) and decreased transmittance (<ca. 10%) and exhibited broadband VIS and NIR absorptions in summer and selective peaks in winter. A simulation coupling water extinction with thallus reflectance and transmittance found seven submerged thalli maximized the surface reflectance enhancement (ca. 2.5%).

Micro-Environment and Plant Assemblage Structure on Virginia's Barrier Island “Pimple” Dunes

Abstract “Pimple” dunes are small, rounded coastal dunes that form along major dune ridges of the barrier islands along the Eastern Shore of Virginia. Although most pimple dunes are small structures ranging between 10 and 20 m in diameter, they have distinct plant assemblages that replicate the upland ecotones of their barrier islands. We examined the relationship between microenvironment, edaphic factors, and plant assemblage structure on pimple dunes. Water availability was an obvious major ecological driver, but we also tested other environmental factors that may correlate with plant assemblage structure. We found distinct assemblage types that segregated themselves by habitat type: marsh, shrub thicket, and dry summit. Freshwater availability was important in delineating vegetation differences, both among transects and among species. However, soil nutrients, such as ammonium, potassium, magnesium, and boron, were also spatially correlated with plant assemblage structure. We hypothesize that interactio...

Marsh love seat, Bull's Landing, Eastern shore of Virginia, 2005

Marsh love seat, Bull's Landing, Eastern shore of Virginia, 2005

The Countryside Transformed: The Eastern Shore of Virginia, the Pennsylvania Railroad, and the Creation of a Modern Landscape

The Countryside Transformed: The Eastern Shore of Virginia, the Pennsylvania Railroad, and the Creation of a Modern Landscape

Service-Learning and Foreign-Language Teacher Education

Jonathan Arries (William and Mary) and Gresilda Tilley-Lubbs (Virginia Polytechnic Institute and State University) facilitated a workshop at the AATSP Annual Meeting in Chicago in July 2003. The objectives were fourfold: to enable teachers involved in Foreign-Language Teacher-Education Programs to (1) gain an understanding of service-learning in teacher-education programs; (2) explore the implications of service-learning as an assessment tool for the ACTFL/NCATE review for accreditation of teacher-education programs; (3) investigate the possibilities of incorporating service-learning as a means of meeting the National Standards in Foreign Language programs K-12, and (4) examine various service-learning models in existing programs. In July 2003,39 million Hispanics became the largest minority in the United States (Census 2000), increasing the likelihood that pre-service teachers will encounter classrooms in which Hispanic children will be included. Therefore, service-learning projects situated in the Hispanic community not only provide an opportunity to link foreign-language education programs to com munity needs; they also provide a means of giving pre-service teachers a firsthand understanding of the community and its culture. The facilitators presented the rationale for and history of service-learning, integrated with sharing about the programs they have established in their respective schools. Both programs are based on critical theory and issues of social justice, creating a transformative experience for the students. The workshop then divided into small groups in which participants discussed their own experiences in teaching. They shared with each other their early years as teachers, focusing on their reactions to diverse populations in the classroom. After sharing with each other, they described their partners' experiences to the larger group, leading to a discussion of the power of authentic community service integrated with academic outcomes (Erickson and Anderson) in the preparation of pre-service teachers. The discussion that followed was framed in the precept that service-learning instills a commitment to social responsibility, social change, and social justice (Cochran-Smith). Partici pating in a service-learning program situated in the Latino community nurtures the valuing of the knowledge and interests, cultural and linguistic resources children bring to school (cf. Cochran Smith; Freir?; Greenberg and Moll). It helps pre-service teachers understand the influences that shape students, such as language, culture, ability, family, and community (cf. Smylie, Bay, and Tozer). Tilley-Lubbs shared research that suggests that teacher education programs consider a new paradigm incorporating service-learning to foster an understanding of diversity, attention to service, concern for social justice, knowledge of the subject area, and development of critical thinking skills (Tilley-Lubbs). To provide models of existing service-learning programs, Arries and Tilley-Lubbs described their own programs (Arries; Tilley-Lubbs). Arries presented the program in which he accompanies a group of students to the Eastern Shore of Virginia for a month. During that time, the students interpret for the migrant workers at the Health Department, providing services for a

Evaluating Indirect Land Use and Environmental Effects of a Toll Discount Proposal

Physical improvements to a transportation network or policy actions such as toll decrease can have an impact on the environment by reducing the time and monetary costs of travel, which can work to enhance the attractiveness of surrounding land to developers, residents, and businesses. A proposed toll discount on the Chesapeake Bay Bridge-Tunnel connecting the Hampton Roads metro area with the rural Eastern Shore of Virginia was analyzed for its potential to influence land use and affect the environment. How practitioners can couple well-established technical assessment methods in various disciplines with public involvement and strategic planning to promote a comprehensive vision of the future for a rural area on the fringe of a growing metropolitan region was illustrated. Current conditions, assets, needs, goals and potential impacts were assessed in several key areas of interest to Eastern Shore residents: transportation, tourism, economic development, agriculture and aquaculture, natural resources, and quality of life (livable communities). The impact assessment examined the potential for effects attributable to toll reduction scenarios in each of these six topic areas. The assessment techniques included interviews, comparative case research, analysis of present and potential future regional development and commuting patterns through the application of a gravity model, and extensive public involvement in the form of public meetings and topic workshops. As a complement to the impact assessment, the study team formulated strategies and actions to manage future growth and development that could be anticipated with or without a reduction in the toll.

Chronicles of Virginia's Shore

Chronicles of Virginia's Shore

Surface reflected signals from the Global Positioning System for ionospheric measurements: Experimental results at aircraft altitudes

Several spaceborne altimeters have been built and flown, and others are being developed, to provide measurements of ocean and ice sheet topography. Until the launch of TOPEX (Ocean Topography Experiment), altimeters were single-frequency systems that were incapable of removing the effects of ionospheric delay on the radar pulse. With the current state-of-the-art in satellite altimetry, the ionosphere causes the largest single error when using single-frequency altimeters. Ionospheric models provide the only recourse short of adding a second frequency to the altimeter. Unfortunately, measurements of the ionosphere are lacking over the oceans or ice sheets where they are most needed. A possible solution to the lack of data density may result from an expanded use of the Global Positioning System (GPS). This paper discusses how the reflection of the GPS signal from the ocean can be used to extend ionospheric measurements by simply adding a GPS receiver and downward-pointing antenna to satellites carrying single-frequency altimeters. The viability of this concept hinges upon the ability to acquire and code-track the reflected signal for an extended period of time over a variety of sea states. The theory of specularly and diffusely reflected radio frequency radiation from a rough surface is reviewed. Results of experiments to demonstrate tracking of a reflected signal are presented for three aircraft flights over the Chesapeake Bay and the Eastern Shore of Virginia. The experimental hardware consisted of two off-the shelf receivers configured such that one received the GPS signal in the conventional manner using a right-hand circularly polarized (RHCP) antenna on top of the fuselage and the other could receive the reflected signal using a left-hand circularly polarized (LHCP) antenna on the bottom of the fuselage. Three tests were performed on the data to verify that the signals received in the bottom antenna were sea surface reflections: pseudorange double differences were compared against predicted geometric range double differences, characteristics of a signal reflected from a random surface were observed in the carrier to noise ratio and predicted specular points were plotted which demonstrate reflection only from wet areas. These tests indicated tracking of reflected signals for extended periods of time at altitudes of up to 5500m and sporadic signal acquisition at higher altitudes.

The Cost of Nutrient Reduction: A Case Study of Chesapeake Bay

Over $3.5 billion were spent toward nutrient controls in the Chesapeake Bay watershed between 1985 and 1996. These expenditures were based on cost-shares between federal, state, local, and private sources and should be considered conservative. A comparison of point and nonpoint nutrient control expenditures in the Bay basin showed that about 50% of the funds were directed toward agricultural best management practices and 45% were allocated for point source nutrient reductions and combined sewer overflows (20% and 25%, respectively). The remainder was spent on various other estuarine-targeted programs. Maryland was responsible for 79% of the total expenditures, 16% was expended by Virginia, and the remainder was attributable to the District of Columbia and Pennsylvania (4% and 1%, respectively). The most costly basin was the Patuxent (over $125 per kilogram of total nitrogen removed) and the least costly was the Eastern Shore of Virginia, where the cost was just under $21 per kilogram of nitrogen removed. For the control practices examined, the analysis found that nutrient management was the least costly. Animal waste control and low tillage were the second and third most economical nutrient management strategies. Significant reductions were achieved from point sources for both total nitrogen (16%) and total phosphorus (53%) by 1996. Virtually all of the large reduction in point source phosphorus was a result of the phosphorus detergent ban implemented basinwide in the late 1980s. Nonpoint source nutrient reductions were more modest. An approximate 12% reduction in phosphorus was accompanied by an 8% reduction in total nitrogen loadings. Despite these nutrient reductions, no significant improvements in bottom-dissolved oxygen levels were detected along the Bay mainstem during the warmer months, and the mouth of Chesapeake Bay showed marginally significant degradation during the 11-year period. It was determined that dissolved oxygen conditions were influenced more by nitrogen than phosphorus reductions and that nutrient controls aimed at the mid-Bay region had the greatest potential for improving low dissolved oxygen conditions in the Bay's bottom waters.

The Distribution of Microbial Communities in Anaerobic and Aerobic Zones of a Shallow Coastal Plain Aquifer.

Randomly amplified polymorphic DNA (RAPD) fingerprinting was used to determine the genetic similarity of whole-community DNA extracts from unattached microorganisms in several groundwater wells. The study site was a shallow coastal plain aquifer on the Eastern Shore of Virginia that contains distinct regions of anaerobic and aerobic groundwater. Several wells in each region were sampled, and principal component and cluster analyses showed a clear separation of the microbial communities from the two chemical zones of the aquifer. Within these zones, there was no relationship between the genetic relatedness of a pair of communities and their spatial separation. Two additional sets of samples were taken at later times, and the same clear separation between communities in the different zones of the aquifer was observed. The specific relationships between wells within each zone changed over time, however, and the magnitude and direction of these changes corresponded to concurrent changes in the groundwater chemistry at each well. Together, these results suggest that local variation in groundwater chemistry can support genetically distinct microbial communities, and that the composition of the microbial communities can follow seasonal fluctuations in groundwater chemistry.

Analyses of recent geomorphic evolution of Gargathy Inlet, eastern shore of Virginia, U. S. A.

Gargathy Inlet is a small natural tidal inlet in the northern region of the Virginia barrier island chain. It is 100 m wide with a throat cross-sectional area of 384 m2 and an average tidal prism of 6.47×106 m3. The inside drainage system is 7.8 km long and 2.2 km wide. The main channels comprise 5.8% of the area, shallow lagoons 19.8%, andSpartina marshes 74.4% in 1970. Over the period 1851–1989 the inlet narrowed and migrated northward while maintaining a weakening downdrift offset. The nearby barrier island coastline’s rapid retreat (average rate 4.78 m/a, 138 years retreat 660 m) was accompanied by back barrier channel and lagoon filling and a decrease in intertidal water volume which was probably the main reason for the entrance narrowing. The northward migration of the inlet was related to the dredging of the Inside Passage (before 1949) and the breaching of southern Metompkin Island (since 1957) connected with the inlet system. This altered the interior tidal circulation and likely shifted northward the divide between the drainage areas of Gargathy Inlet and Metompkin Inlet. Bypassing littoral sediment from north to south, downdrift local transport reversal, and onshore welding of swash bars formed a downdrift offset. Very strong coastal storms, particularly those of 1933 and 1962, played important roles in changing inlet geometry.

Evaluation of Various Potato Plant Sample Units for Cost-Effective Sampling of Colorado Potato Beetle (Coleoptera: Chrysomelidae)

Sampling for larvae and adults of Colorado potato beetle, Leptinotarsa decemlineata (Say), was done in commercial potato, Solanum tuberosum L., fields on the Eastern Shore of Virginia in 1987 and 1988 to evaluate sampling precision and cost associated with a single potato stem versus two- to five-stem cluster sample units. Relative net precision values indicated that five-stem cluster samples were the most cost efficient for all population densities of Colorado potato beetle larvae and adults. When plants attain maximum vegetative growth, cluster samples of three or four stems may be used to save time with only a small sacrifice in sampling precision compared with five-stem cluster samples. Additional sampling was done in 1987 to compare Colorado potato beetle counts from upper plant foliage with whole-plant counts to determine whether a visual examination of the top plant canopy could be used to estimate beetle density on the whole plant. Coefficient of determination values generated from regression analyses of top-foliage beetle counts on whole-plant counts were higher for adults than for large larvae. However, a large proportion of the total variation in whole-plant counts was explained by the fitted regressions for both life stages.

Nitrogen cycling between sediment and the shallow-water column in the transition zone of the Potomac River and Estuary. II. The role of wind-driven resuspension and adsorbed ammonium

During periods of sediment resuspension, desorption of ammonium from sediment solids can be the major pathway for enriching the water column with the ammonium that is produced by bacterial degradation of organic matter in the bottom material. This hyopthesis is based on a three-year study of diffusive flux in the transition zone of the Potomac River at a site 35 m from the Virginia shore where the average water-column depth is approximately 1 m over sandy sediment. A diffusion-controlled sampler was used to collect water samples at the interface between the water column and sediment and at several tens of centimeters into the sediment. Interstitial water concentration gradients showed that diffusive flux of ammonium from the sandy shallow-water sediments was approximately 1% of the diffusive flux of ammonium from the silty channel sediments in the same zone of the Potomac River. Organic nitrogen and bound or adsorbed ammonium were the predominant nitrogen forms in the sediment. Adsorbed ammonium concentrations ranged from nondetectable to 3·7 μmol g −1 of sediment. Concentrations of adsorbed ammonium per gram of sediment were one to three orders of magnitude more than interstitial water ammonium concentrations. Desorption of ammonium from sediment solids appeared to be the controlling factor in the degree of water-column ammonium enrichment. In laboratory experiments that simulated sediment resuspension, 40–80% of the adsorbed ammonium predicted to desorb did so after approximately 30 min of mixing. Based on calculations for 1 m 2 to a depth of 4 cm, one resuspenion event lasting minutes could mix more ammonium into the water column from desorption of ammonium from sediment solids than could be delivered to the water column by diffusive flux from shallow-water sediments in 10–1000 days and would be comparable to enrichment by ammonium diffusive flux for 5–50 days from channel sediments in the same river zone.

Nitrogen cycling between sediment and the shallow-water column in the transition zone of the Potomac River and estuary. I. Nitrate and ammonium fluxes

A three-year study of seasonal variation in water-column and sediment nitrogen species was conducted in the transition zone of the Potomac River 35 m from the Virginia shore at a site with an average water-column depth of approximately 1 m over sandy sediment. A diffusion-controlled sampler was used to collect water samples from the water column, at the interface between the water column and sediment, and at several tens of centimeters into the sediment. Nitrate was the predominant dissolved nitrogen species in the water column. The importance of denitrification was inferred by nitrate fluxes which were directed into the sediment from the water column during approximately 75% of the sampling periods and ranged from 0·02 to 0·69 mmol m −2 day −1. Flux of nitrate from the sediment into the water column, ⩾0·1 mmol m −2 day −1, due possibly to nitrification in surficial sediment, occurred during one spring and two summer sampling periods. Ammonium fluxes were less than 0·1 mmol m −2 day −1 during 90% of the sampling periods. Of the ammonium fluxes that were >0·05 mmol m −2 day −1, all were fluxes into the sediment during sampling periods when sediment resuspension occurred, and all were into the water column during periods of calm. The mean value of ammonium flux (0·005 ± 0·05 mmol m −2 day −1) from the sandy, shallow-water sediments was two orders of magnitude less than the ammonium fluxes from the deeper, silty channel sediments in the same reach of the river. Diffusive flux calculations suggest that approximately one order of magnitude more nitrate than ammonium is cycled between the shallow-water column and the sandy sediment in the transition zone of the Potomac River.