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Physical Sciences and Mathematics Commons

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2002

Environmental Sciences

Dissertations, Theses, and Masters Projects

Articles 1 - 10 of 10

Full-Text Articles in Physical Sciences and Mathematics

Use Of Remote Sensing To Identify Essential Habitat For Aeschynomene Virginica (L) Bsp, A Threatened Tidal Freshwater Wetland Plant, Elizabeth M. Mountz Jan 2002

Use Of Remote Sensing To Identify Essential Habitat For Aeschynomene Virginica (L) Bsp, A Threatened Tidal Freshwater Wetland Plant, Elizabeth M. Mountz

Dissertations, Theses, and Masters Projects

No abstract provided.


Predicting Metal Interactions With A Novel Quantitative Ion Character -Activity Relationship (Qicar) Approach, David R. Ownby Jan 2002

Predicting Metal Interactions With A Novel Quantitative Ion Character -Activity Relationship (Qicar) Approach, David R. Ownby

Dissertations, Theses, and Masters Projects

Environmental toxicologists adopted QSARs from pharmacology fairly early on to predict organic contaminant toxicity. In contrast, models relating metal ion characteristics to their bioactivity remain poorly explored and underutillized. Quantitative Ion Character-Activity Relationships (QICARs) have recently been developed to predict metal toxicity. The QICAR approach based on metal-ligand binding tendencies has been applied to a wide range of effects, species, and media on a single metal basis. In previous single metal studies, a softness parameter and the ; log of KOH ; were the ion qualities with the highest predictive value for toxicity. Here, QICAR modeling was brought a step …


Development Of A Watershed And Stream-Reach Spawning Habitat Model For River Herring Alosa Pseudoharengus And Alosa Aestivalis, Rebecca A. Boger Jan 2002

Development Of A Watershed And Stream-Reach Spawning Habitat Model For River Herring Alosa Pseudoharengus And Alosa Aestivalis, Rebecca A. Boger

Dissertations, Theses, and Masters Projects

This research develops a model to identify indicators of potential suitable spawning habitat for river herring, Alosa pseudoharengus and A. aestivalis, using watershed and stream-reach metrics. The results of icthyoplankton samples collected from thirty-four streams feeding into the Rappahannock River below the Embree Dam at Fredericksburg indicate where river herring spawning occurred. Watershed and stream-reach metrics were either measured in the field or derived from digital data in a GIS. Benthic macroinvertebrate analysis was used to compare habitat quality among sites. Streams were classified as either absence or presence of herring eggs or larvae based on the results of the …


Effects Of Habitat Fragmentation On The Utilization Of Eelgrass (Zostera Marina) By Mobile Epifauna And Macrofauna, Scott R. Marion Jan 2002

Effects Of Habitat Fragmentation On The Utilization Of Eelgrass (Zostera Marina) By Mobile Epifauna And Macrofauna, Scott R. Marion

Dissertations, Theses, and Masters Projects

The threat to biodiversity posed by increasing rates of anthropogenic habitat fragmentation necessitates an understanding of the consequences of spatial pattern for natural communities. Reduction of patch size, loss of habitat, changes in the quantity and proportion of habitat edge, and reduced connectivity among habitats can all shape ecological processes and faunal behavior. Seagrass habitats provide a natural model system for examining spatial inf1uences on marine fauna, but separating the effects of habitat structure, environmental conditions, and spatial pattern is difficult because shoot density, percent cover, and hydrodynamic regime often co-vary with patch size. This study used experimentally manipulated seagrass …


Comparison Of The Fate Of Dissolved Organic Matter In Two Coastal Systems: Hog Island Bay, Va (Usa) And Plum Island Sound, Ma (Usa), Tami L. Lunsford Jan 2002

Comparison Of The Fate Of Dissolved Organic Matter In Two Coastal Systems: Hog Island Bay, Va (Usa) And Plum Island Sound, Ma (Usa), Tami L. Lunsford

Dissertations, Theses, and Masters Projects

No abstract provided.


The Development Of A Water Quality Model In Baltimore Harbor, Back River, And The Adjacent Upper Chesapeake Bay, Hui Liu Jan 2002

The Development Of A Water Quality Model In Baltimore Harbor, Back River, And The Adjacent Upper Chesapeake Bay, Hui Liu

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Urbanization And Land Use On Pah Accumulation In Wetland Sediments, Kimani L. Kimbrough Jan 2002

Effects Of Urbanization And Land Use On Pah Accumulation In Wetland Sediments, Kimani L. Kimbrough

Dissertations, Theses, and Masters Projects

The relationship between wetland polycyclic aromatic hydrocarbon (PAH) concentrations and adjacent land use was assessed using surface sediments, sediment cores and global information systems (GIS) in the Elizabeth River, Virginia, an urbanized subestuary of the Chesapeake Bay. Wetlands adjacent to parking lots and petroleum industrial sites exhibited the highest PAH concentrations of all land uses in surfaces sediment and historically. Automobile and coal are the dominant sources of PAHs in wetland sediments historically as determined by relative concentration, fingerprinting and source specific compounds. An analysis of variance (ANOVA) test used to compare sixteen surface sediment sites based on land use …


Coastal Zone Landscape Classification Using Remote Sensing And Model Development, Kevin R. Slocum Jan 2002

Coastal Zone Landscape Classification Using Remote Sensing And Model Development, Kevin R. Slocum

Dissertations, Theses, and Masters Projects

Coastal zone landscape characterization and empirical model development were evaluated using multi-spectral airborne imagery. Collectively, four projects are described that address monitoring and classification issues common to the resource management community. Chapter 1 discusses opportunities for remote sensing. Chapter 2 examines spectral and spatial image resolution requirements, as well as training sample selection methods required for accurate landscape classification. Classification accuracy derived from 25nm imagery with 4m pixel sizes outperformed 70nm imagery with 1m pixel sizes. Eight natural and five cultural landscape features were tested for classification accuracy. Chapter 3 investigated the ability to characterize 1m multispectral imagery into rank-ordered …


Oyster Reef Restoration In Virginia: Broodstock Addition & Nutrient Exchanges, Laurie Ann Sorabella Jan 2002

Oyster Reef Restoration In Virginia: Broodstock Addition & Nutrient Exchanges, Laurie Ann Sorabella

Dissertations, Theses, and Masters Projects

No abstract provided.


Fate Of Organic Compounds Associated With Extractable And Bound Phases Of Estuarine Sediments Deposited Under Varying Depositional Regimes, Krisa Murray Arzayus Jan 2002

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 …