Earth Sciences Commons^™

Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran

Undergraduate Honors Theses

Anthropogenic activities generate metal, acid, and particulate air pollutants which negatively impact human and ecological health. In the United States, power plant, industrial, and vehicle emissions are leading causes of air pollution, however, the measurement of air pollution at high-resolution spatial regimes remains a challenge. Honey has emerged as a powerful biomonitoring tool to effectively quantify contaminants without the need for a large array of monitoring instruments. I hypothesized that honey could be used to effectively measure and map modern air pollutant spatiotemporal relationships over the Eastern U.S. Using ion chromatography with sulfate as an indicator for air pollution and …

Ecosystem Enriching And Efficient Solar Energy: Exploring The Effects Of Pollinator-Friendly Solar Facilities On Ecosystem Function And Solar Panel Efficiency, Jordan Martin

Dissertations, Theses, and Masters Projects

As the solar energy industry grows, many hundreds of thousands of acres of land will be transformed into solar panel facilities. With this large change in land use, there is the opportunity to promote biodiversity and support pollinators by using pollinator-friendly management practices at the solar facilities. This paper explores the ecological and economic effects of a pollinator-friendly solar facility compared to a turfgrass solar facility.

I hypothesized that a pollinator-friendly solar facility would be functionally equivalent in pollinator support and overall insect diversity to a pollinator-friendly non-solar field and that both sites would have far greater pollinator support and …

Three Centuries Of Vegetation Change In The William & Mary College Woods Reconstructed Using Phytoliths, Timothy Terlizzi

Undergraduate Honors Theses

The College Woods, west of William & Mary’s campus, consists of ~900 acres of protected southern mixed hardwood forest. The woods surround Lake Matoaka, a former millpond established in ~1700. Despite the rich history of the area, little is known about how the dominant vegetative landcover has shifted over the last 300 years. This study set out to quantify the modern vegetation within the College Woods via the phytolith assemblages within the soil and identify shifts in the assemblages since the creation of Lake Matoaka and whether these changes are distinct from the vegetation that existed in the area before …

Storm Event Impact On Organic Matter Flux, Composition And Reactivity In Taskinas Creek, Va, Sarah Schillawski Cammer

Dissertations, Theses, and Masters Projects

Carbon export from the land to the ocean are an important part of the global carbon cycle, linking terrestrial watersheds and the global carbon cycle. Burial of terrestrial organic carbon represents a long term sink for atmospheric CO2. Approximately 0.4 Pg Cy-1 is delivered to the global ocean from rivers, equally divided between POC and DOC. However, the amount of carbon entering the ocean is a small portion of the total amount entering rivers from the terrestrial environment, suggesting a large amount of processing in inland waters and estuaries. Most monitoring efforts have focused the processing of organic matter on …

Spatial And Temporal Patterns In Erosional And Depositional Processes: Physical And Biological Controls In The York River, Chesapeake Bay, Virginia, Cielomar Rodríguez-Calderon

Dissertations, Theses, and Masters Projects

No abstract provided.

Interactions Between Macroalgae And The Sediment Microbial Community: Nutrient Cycling Within Shallow Coastal Bays, Amber Kay Hardison

Dissertations, Theses, and Masters Projects

Ephemeral macroalgal blooms are considered a symptom of eutrophication in shallow coastal lagoons, but their influence on nutrient cycling dynamics in these systems is not fully understood. From 2006-2008, I conducted a series of experiments to determine the influence of living and senescent macroalgae on sediment carbon (C) and nitrogen (N) cycling in coastal lagoons along the Delmarva Peninsula, USA. In particular, I focused on how macroalgae affect the microbial community at the sediment-water interface of shallow subtidal sediments because this complex consortium of autotrophic (e.g. benthic microalgae, BMA) and heterotrophic (e.g. bacteria) organisms plays a critical role in nutrient …

The Impact Of Drainage Ditches On Salt Marsh Flow Patterns, Sedimentation And Morphology: Rowley River, Massachusetts, Lynsey E. Lemay

Dissertations, Theses, and Masters Projects

Salt marshes along many tidal systems in New England have been ditched since colonial times. These ditches have been thought to help control mosquito populations and increase salt marsh hay production by improving water drainage from the marsh. Although these ditches are prominent geomorphic features, little quantitative work has focused on how these man-made ditches may alter marsh hydrology and geomorphology. This study attempts to quantify the ways in which ditches alter sediment and water transport pathways and how that affects the overall morphology and surface geology. This study also addresses treatment affects on sedimentation from fertilization and fish removal …

Disposition Of Wastewater-Associated Polybrominated Diphenyl Ethers In A Freshwater Receiving Stream, Mark Joseph La Guardia

Dissertations, Theses, and Masters Projects

No abstract provided.

Planar Oxides As A Novel Approach To Metal Ion Sorption Studies: From The Lab To The Field, Christine F. Conrad

Dissertations, Theses, and Masters Projects

The purpose of this work is to investigate the use of planar oxides as tools for metal ion sorption studies that can be used in both laboratory and field settings. to do this, a three-step approach was used. In the first step, the reactivities of the planar gamma-Al2O3 surfaces relative to pure phase gamma alumina was investigated through Pb(II) sorption studies. The relative quantitative uptake of Pb(II) on the planar gamma alumina was found to be comparable to that on the bulk. XAS analysis showed that the coordination geometry and local binding environment of the Pb(II) complexes were similar on …

Fate Of Organic Compounds Associated With Extractable And Bound Phases Of Estuarine Sediments Deposited Under Varying Depositional Regimes, Krisa Murray Arzayus

Dissertations, Theses, and Masters Projects

Surficial sediments and sediment cores were collected from two distinct depositional regimes of the York River subestuary of Chesapeake Bay to document seasonal inputs, spatial variability, and longer-term (>40 years) fate of total organic carbon (TOC), lipid biomarker compounds and polycyclic aromatic hydrocarbons (PAHs). These regimes included biological mixing in the lower York and episodic mixing at the mid river site. Compounds were selected to represent a range of chemical reactivities, biological and anthropogenic sources, and modes of entry to the environment. The depositional environments were characterized with a suite of analytical tools: x-radiographs, Eh, 210Pb and 137Cs, total …

Persistent Organic Pollutant Transport And Fate: Assessment By Molecular Tracers, Padma T. Venkatraman

Dissertations, Theses, and Masters Projects

Persistent organic pollutants (POPs) such as the organochlorine pesticide hexachlorocyclohexane (HCH) may undergo atmospheric transport and accumulate in regions remote from the source. It is important to develop techniques to help apportion source and identify transport or transformation processes to which HCHs and other mobile POPs may be subjected. Molecular tracers such as compound specific stable isotope and enantiomer ratios (ERs) may prove valuable in studying POP fate and transport. The objective of this study was to further develop the use of these two novel geochemical tools to evaluate the sources, transport and environmental fate of POPs, in the context …

Sand- And Clay-Size Mineralogy Of The Ganges And Brahmaputra Rivers: Records Of River Switching And Late-Quaternary Climate Change, David Carlson Heroy

Dissertations, Theses, and Masters Projects

No abstract provided.

Geochemistry Of Small Mountainous Rivers Of Papua New Guinea: Local Observations And Global Implications, Megan B. Raymond

Dissertations, Theses, and Masters Projects

Small, wet mountainous rivers (runoff > 0.63 m yr" 1 , headwater elevation> 1000 m, basin area < 10,000 km2 ) contribute a disproportionate amount of sediment to the global ocean due to their steep high topography, erosive substrate, and often high precipitation. Scattered data have suggested a slight, but statistically insignificant, inverse relationship between total dissolved solid (TDS) yield (T km-2 yr-1 ) and basin area, but small to very small rivers (basin areas< 10,000 km2 ) have been poorly documented. To fill this data gap, as well as to elucidate possible links between weathering and basin hydrology, nine small wet mountainous rivers, basin areas 22 km2-2300 km2 , were sampled in late May 1997 in northeastern Papua New Guinea. TDS concentrations ranged from 75 to 148 mg L-1 , with no correlation to watershed area. The dissolved organic carbon (DOC) and particulate organic carbon (POC) values were low, with a mean DOC value of 135 f.Lmol L-1 ; POC values were lower, averaging 3lf.Lmol L- 1 • TDS data, combined with large wet mountainous river TDS data, demonstrate a significant inverse relationship between TDS yield and basin area. As a result, small wet mountainous rivers contribute a disproportionate amount of TDS, and have the highest TDS yields of any class of river. This observation is attributed to the high runoff of the sampled rivers (-2m yr-1 ), in addition to high rates of chemical weathering, which is facilitated by the erosive substrate and high rates of organic matter remineralization.

Polycyclic Aromatic Hydrocarbon (Pah) Distributions Within Urban Estuarine Sediments, Siddhartha Mitra

Dissertations, Theses, and Masters Projects

Sediments and pore waters from two urban estuaries ranging in sediment mixing energy were studied to evaluate the potential release of contaminants from particles during sediment diagenesis. Two sites in Elizabeth River, VA and two tributaries in the Hudson River Watershed were sampled for polycyclic aromatic hydrocarbons (PAHs). Sediment age, total sediment organic carbon (TOC), carbon to nitrogen (C/N) ratios, and particle surface area (SA) were also sampled at these sites. In the Elizabeth River, both sites sampled (Site 1 and Site 2) have been non-depositional for the past 70 y or are comprised of old dredge spoil. PAH K&\sp\prime\sb{lcub}\rm …

Studies On Processes Controlling The Input Of Agricultural Chemicals In Groundwater To Surface Waters, Edward Laurence Libelo

Dissertations, Theses, and Masters Projects

This dissertation describes several studies of groundwater quality, the fate and transport of nutrients and atrazine in groundwater systems and physical processes at the sediment-water interface which impact on groundwater discharge. Groundwater monitoring wells were installed at the Goodwins Island and Catlett Island NERRS sites in Virginia and agricultural, suburban and forest land use sites in the York and James River Basins. Groundwater was analyzed for nutrients, pH, salinity and trace organics. Shoreline land use, associated nutrient loading and an estimate of total groundwater flux suggest that groundwater contributes up to 30% of the total nitrogen input to the Chesapeake …

A Numerical Model Of The Global Carbon Cycle To Predict Atmospheric Carbon Dioxide Concentrations, Alexis Demitrios Kambis

Dissertations, Theses, and Masters Projects

A numerical model of the global carbon cycle is presented which includes the effects of anthropogenic &CO\sb2& emissions &(CO\sb2& produced from fossil fuel combustion, biomass burning, and deforestation) on the global carbon cycle. The model is validated against measured atmospheric &CO\sb2& concentrations. Future levels of atmospheric &CO\sb2& are then predicted for the following scenarios: (1) Business as Usual (BaU) for the period 1990-2000; (2) Same as (1), but with no biomass burning; (3) Same as (1), but with no fossil fuel combustion; (4) Same as (1), but with a doubled atmospheric &CO\sb2& concentration and a 2 K warmer surface temperature …

An Analysis Of Wetland Total Phosphorus Retention And Watershed Structure, Megan K. Greiner

Dissertations, Theses, and Masters Projects

No abstract provided.

Sorption Of Nonpolar Organics On Minerals And Aquifer Materials, Thomas B. Stauffer

Dissertations, Theses, and Masters Projects

The sorption of nonpolar organic chemicals on hydrous oxides, clay minerals, and subsurface aquifer materials was studied using the batch isotherm technique. Radiolabeled (&\sp{lcub}14{rcub}&C) trichloroethylene, orthodichlorobenzene, naphthalene, and 1-methylnaphthalene were sorbed on mineral sorbents, subsurface aquifer materials, and a surface soil at six different equilibrium concentrations over a concentration range from 0.001 mg/L to 1.0 mg/L. A knowledge of the sorption coefficients of these fuel components and solvents is necessary to predict the transport of these chemicals through groundwater systems and ultimately to rivers, lakes, and estuaries. Sorption on oxides and surface soils was found to be pH-dependent with decreased …

A Mathematical Model For Small Tidal Streams Capable Of Simulating Both Short-Term And Long-Term Water Quality Variations, Stephen Anthony Williams

Dissertations, Theses, and Masters Projects

No abstract provided.

Fatty Acids And Hydrocarbons In The Surface Waters Of The York River, John G. Windsor

Dissertations, Theses, and Masters Projects

No abstract provided.