A5052498685- Marine and coastal ecosystems
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Atmospheric and Environmental Gas Dynamics
- Methane Hydrates and Related Phenomena
- Toxic Organic Pollutants Impact
- Coastal wetland ecosystem dynamics
- Hydrocarbon exploration and reservoir analysis
- Marine Biology and Ecology Research
- Marine Bivalve and Aquaculture Studies
- Marine and coastal plant biology
- Microbial Community Ecology and Physiology
- Groundwater and Isotope Geochemistry
- Marine and environmental studies
- Metabolomics and Mass Spectrometry Studies
- Algal biology and biofuel production
- Coastal and Marine Dynamics
- Aeolian processes and effects
- Marine and fisheries research
- Ocean Acidification Effects and Responses
- Soil and Water Nutrient Dynamics
- Wastewater Treatment and Nitrogen Removal
- Mercury impact and mitigation studies
- Coral and Marine Ecosystems Studies
- Archaeology and ancient environmental studies
William & Mary
2013-2024
Virginia Institute of Marine Science
2001-2016
Physical Sciences (United States)
2013
University of Michigan
2010
Old Dominion University
2010
University of North Carolina at Chapel Hill
1990-1996
United States Geological Survey
1995
Woods Hole Oceanographic Institution
1984-1986
We report measurements of seasonal variability in the C‐N stable isotope ratios plants collected across habitat mosaic San Francisco Bay, its marshes, and tributary river system. Analyses 868 plant samples were binned into 10 groups (e.g., terrestrial riparian, freshwater phytoplankton, salt marsh) to determine whether isotopes can be used as biomarkers for tracing origins organic matter this river‐marsh‐estuary complex. Variability δ 13 C 15 N was high (~5–10‰) within each group, we...
We analyzed >400 particulate samples collected from throughout the Chesapeake Bay region between 1991 and 1998 for polycyclic aromatic hydrocarbons (PAHs). Isomer ratios of PAHs associated with aerosol surface water particles demonstrate that motor vehicles are a major source carcinogenic combustion-derived to Bay. Most benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene their isomers in air, rain, waters appear be derived automotive sources. Lesser, but still significant amounts...
Abstract Carbon cycling in the coastal zone affects global carbon budgets and is critical for understanding urgent issues of hypoxia, acidification, tidal wetland loss. However, there are no regional spanning three main ecosystems waters: wetlands, estuaries, shelf waters. Here we construct such a budget eastern North America using historical data, empirical models, remote sensing algorithms, process‐based models. Considering net fluxes total at domain boundaries, 59 ± 12% (± 2 standard...
Abstract High plant species richness can enhance primary production, animal diversity, and invasion resistance. Yet theory predicts that herbivore which often covary in nature, should have countervailing effects on ecosystem properties. Supporting this, we show a seagrass system increasing grazer diversity reduced both algal biomass total community facilitated dominance of grazer‐resistant invertebrate. In parallel with previous results, however, enhanced secondary critical determinant fish...
Multiple indicators (Chl a, C: N ratios, [ δ 13 C]POC, and two classes of lipid biomarker compounds—sterols phospholipid ester‐linked fatty acids) were used to evaluate spatial temporal variations in the origin particulate organic matter (POM) San Francisco Bay (SFB) estuary. Comparisons made between northern southern subestuaries SFB, as well along salinity gradient SFB. Two sample types collected—seston, which was characterize bulk POM, tissues suspension‐feeding bivalve Potamocorbula...
This textbook provides a unique and thorough look at the application of chemical biomarkers to aquatic ecosystems. Defining biomarker as compound that can be linked particular sources organic matter identified in sediment record, book indicates these for an understanding ecosystems consists biogeochemical approach has been quite successful but underused. offers wide-ranging guide broad diversity biomarkers, is first structured around compounds themselves, examines them connected...
Abstract Photochemical and microbial transformations of DOM were evaluated in headwater streams draining forested human‐modified lands (pasture, cropland, urban development) by laboratory incubations. Changes DOC concentrations, isotopic signatures, fluorescence properties measured to assess the amounts, sources, ages, reactive refractory under influence photochemistry and/or bacteria. forest‐dominated watersheds was more photoreactive than mostly watersheds, possibly due greater...
Estuaries are among the most altered and vulnerable marine ecosystems. These ecosystems will likely continue to deteriorate owing increased population growth in coastal regions, expected temperature precipitation changes associated with climate change, their interaction each other, leading serious consequences for ecological societal services they provide. A key function of estuaries is transfer, transformation, burial carbon other biogenic elements exchanged between land ocean systems....
Organic carbon is important in regulating ecosystem function, and its source abundance may be altered by urbanization. We investigated shifts organic quantity quality associated with urbanization restoration, potential effects on denitrification at the riparian–stream interface. Field measurements of streamwater chemistry, characterization, laboratory‐based experiments were completed two forested, restored, unrestored urban streams Baltimore Long‐Term Ecological Research site, Maryland, USA....
We examined the isotopic compositions of fatty acids, sterols, and hydrocarbons isolated from three coastal macrophytes ( Zostera marina, Spartina alterniflora, Juncus roemerianus ) in order to investigate relative contribution these vascular plants as sources organic matter sediments such Cape Lookout Bight, North Carolina. On average, lipid biomarker compounds extracted were depleted 13 C by 3–5‰ δ total carbon (TOC). However, individual within each class varied up 5.6‰. Trends lipids...