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Physical Sciences and Mathematics Commons™

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Environmental Sciences

Old Dominion University

2005

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Assessment Of Human Health Risks From Chemically Contaminated Lake Fishes In Greece, Eugene G. Maurakis, David V. Grimes, Dimitra Bobori, Rob Hale, Jennifer Jones Oct 2005

Assessment Of Human Health Risks From Chemically Contaminated Lake Fishes In Greece, Eugene G. Maurakis, David V. Grimes, Dimitra Bobori, Rob Hale, Jennifer Jones

Virginia Journal of Science

Objectives were to conduct screening level surveys of locally consumed fish tissues in vicinities of two lakes (Kastoria and Pamvotis) in Greece to determine the presence of halogenated organic compounds and determine carcinogenic and non-carcinogenic human health risks associated with the consumption of sampled fish tissues. Results estimate the Incremental Lifetime Cancer Risks (ILCR) and Hazard Index (HI) values for the two local populations using site-specific population data. These results were compared to analyses conducted using U.S. Environmental Protection Agency default values in an effort to determine the applicability of USEPA default values to assessments of risks in non U.S. …

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Effects Of Human Disturbances On The Behavior Of Wintering Ducks, Melissa L. Pease, Robert K. Rose, Mark J. Butler Jan 2005

Effects Of Human Disturbances On The Behavior Of Wintering Ducks, Melissa L. Pease, Robert K. Rose, Mark J. Butler

Biological Sciences Faculty Publications

Human activity causes wintering waterfowl to expend energy to avoid humans at a time in their annual cycle when energy conservation is important to survival, migration, and breeding reserves. Understanding the effects of recreational activities on waterfowl is important to managing natural resource areas where migratory birds depend on wetland habitat for resting and feeding. We investigated responses of 7 species of dabbling ducks to 5 different experimental human activities, (a pedestrian, a bicyclist, a truck traveling at 2 different speeds, and an electric passenger tram). Responses of ducks depended on type of disturbance, species, and distance from disturbances. Most …

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Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose Jan 2005

Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose

Biological Sciences Faculty Publications

Oryzomys palustris (marsh rice rat) and Microtus pennsylvanicus (meadow vole) cohabit coastal marshes in the mid-Atlantic US. Both were live-trapped for 23 months at two tidal marsh sites in Virginia to assess their demography near the margins of their distributions. In the presence of dense vegetation, population dynamics of the two species were seasonal and positively correlated, with densities declining through the winter. At the more sparsely vegetated site, densities of both species were lower, and densities of M. pennsylvanicus were negatively correlated with those of O. palustris. Patterns of reproduction differed between the species. O. palustris was reproductively …

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Burial Of Terrestrial Organic Matter In Marine Sediments: A Re-Assessment, David J. Burdige Jan 2005

Burial Of Terrestrial Organic Matter In Marine Sediments: A Re-Assessment, David J. Burdige

OES Faculty Publications

Calculations based on recent observations indicate that approximately one third of the organic matter presently being buried in marine sediments may be of terrestrial origin, with the majority of this terrestrial organic matter (TOM) burial occurring in muddy, deltaic sediments. These calculations further suggest that the remineralization of terrestrial organic matter in the oceans is also much less efficient than that of marine organic matter. These two underappreciated observations have important implications in terms of our understanding of the controls on the global carbon cycle. From a paleoceanographic perspective, the results presented here also suggest that changes in TOM burial …

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Ridding Ships' Ballast Water Of Microorganisms, Fred C. Dobbs, Andrew Rogerson Jan 2005

Ridding Ships' Ballast Water Of Microorganisms, Fred C. Dobbs, Andrew Rogerson

OES Faculty Publications

( First paragraph) A complex assemblage of microorganisms exists in nearly every aquatic system on earth. In lakes and oceans, every milliliter of water contains about 102 protists (single-celled eukaryotes), 106 bacteria, and 107–109 viruses. Therefore, billions of microorganisms inevitably enter ships’ ballast tanks during normal operations. It has been argued that microorganisms must certainly be frequent invaders of coastal ecosystems, given the high densities of bacteria and viruses in ballast water—108 and 109 organisms per liter, respectively (1)—their potentially high reproductive rates, broad tolerances to physical conditions, and ability to form resting …

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