Study of channel sediments, James River & Hampton Roads area

Bottom sediment samples were collected from 3 locations transecting the channel in the lower James and Elizabeth rivers

The Effect Of Tropical Storm Agnes On Heavy Metal And Pesticide Residues In The Eastern Oyster From Southern Chesapeake Bay

The concentrations of cadmium, copper, and zinc in the eastern oyster, Crassostrea virginica, are compared for samples collected before and after Tropical Storm Agnes. The before samples consisted of 475 animals from 95 stations collected in January 1971 and the after samples of 285 animals from 57 stations collected in January 1973. Shifts in the areal concentrations distributions were observed, apparently due to Agnes. Analyses of hard clams, blue crabs and oysters for chlorinated hydrocarbon pesticides showed influx of these compounds to be minimal as reflected by the residue levels observed. Comparison of residue levels in oysters to pre-Agnes conditions revealed a decrease in pesticide body burden.https://scholarworks.wm.edu/vimsbooks/1069/thumbnail.jp

Methods for measuring ecosystem stress

If one looks back over the past twenty-five years, at the pollution crises which have made the headlines and influenced our decision making policies on both local and national levels, one may note a very interesting aspect. That is, the crises are often associated with the development of new and more sensitive types of analytical instrumentation. Several examples of this readily come to mind: for example, it wasn\u27t until the development of electron capture detection for gas chromatography that DDT really became a crisis. The reason is quite simple: the concentrations which were being accumulated by the organisms were below detection limits of most available instrumentation. Another example is mercury. The advent of atomic absorption spectrophotometry and the refinement of the the flameless method for mercury allowed the mercury problem to be investigated. New instrumentation doesn\u27t cause the crisis, it merely finds it.https://scholarworks.wm.edu/vimsbooks/1135/thumbnail.jp

Contaminants in Chesapeake Bay: The Regional Perspective

Industrial and municipal point sources of contaminants are scattered along the shores of Chesapeake Bay and its tributaries, but reach especially high density at Norfolk, Va., and Baltimore, Md. Sedimentation and various chemical processes in many cases conspire to restrict the water-borne transport of contaminant away from point source . Kepone, residual chlorine, volatile halogenated hydrocarbons, and anthropogenic trace metals are well-studied example of point-source contaminants. For the most part, their concentration in water and sediment drop to nearly immeasurable values within a distance of a few kilometers, or sometimes a few tens of kilometers, from their source . On the other hand, certain contaminants have now been shown to be truly regionally dispersed. Included are polychlorinated biphenyls, phthalate esters, anthropogenic trace metal (Cu, Zn, Pb), polycyclic aromatic hydrocarbons, herbicides and weapon derived radionuclides. Most of these enter the Bay in significant amount from the atmosphere. Thus their dispersion throughout the Bay is not dependent on aquatic tranport processes. Although it is tempting to link the existence of this regional contamination with well publicized regional biological problem , no link has yet been proven.https://scholarworks.wm.edu/vimsbooks/1058/thumbnail.jp

Organic Chemicals in Sediments from the Lower Chesapeake Bay

Many of the toxic organic chemicals affecting the marine environment are hydrophobic and associate with sediments. Sediments can accumulate the substances over long intervals and store them after the original source of the toxic material has been eliminated. Contaminated sediments can provide small but damaging amounts of the to.xicant to the overlying water for decades. For example, more than 10 years after the discovery of Kepone in the James River, Virginia, much of the James\u27 fisheries ·is still closed because Kepone levels are above federal action levels.https://scholarworks.wm.edu/vimsbooks/1166/thumbnail.jp

Study of channel sediments, Baltimore Harbor, Norfolk Harbor, York entrance channel

3ot~om sediment samples were collected from seven channel locations in the Chesapeake Bay and communicating river systems. The sampling format involved. long cores (designated L ) taken at two nautical mile intervals and surface samples (designated S) taken at one-half mile intervals

Richmond Crater James River Water Quality Management Program, final report 1984-85 and summary, toxic organics in sediments : a final report to Richmond Regional Planning District

The following report contains detailed results of analyses of sediment grabs and cores from the James and Appomattox rivers and some nearby locations for a spectrum of organic toxics. Some data has been previously reported in interim progress reports, but will be included for completeness. A study of variability of replicate samples taken at a single station (JR4). not included in the proposal, presents possible limitations of interpretation of temporal and station to station results. Finally, a comprehensive summary of toxic organics in the sediments of the James River and certain tributarjes over a two-year period will be presented

Distribution of copper and zinc in oysters and sediments from three coastal-plain estuaries.

Copper and zinc were analyzed in oysters (Crassostrea virginica) from the Newport River estuary, North Carolina, and the Rappahannock River estuary, Virginia. Results indicated that a concentration gradient existed, higher concentrations of metals being found in animals living in fresher waters as was shown previously for oysters in the James, York, and Rappahannock estuaries in Virginia. Absorbed, precipitatcd-coprecipitated, and organic fractions of copper and zinc in the \u3c63-μm portion of the sediments from the Rappahannock and York rivers and estuaries were estimated from collections made in January 1972 and June 1973. These sediment data are discussed for both estuarine systems and are compared with metal concentrations in oysters. These comparisons indicated that the concentration gradient found in oysters does not appear to be related to the distribution of copper and zinc in the sediments. Alternative explanations for the inverse relationships between concentrations of copper and zinc in oysters and salinity arc given.https://scholarworks.wm.edu/vimsbooks/1146/thumbnail.jp