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Oyster Spatfall On Shellstrings In Virginia Rivers: 1973 Annual Summary, Dexter S. Haven, Paul C. Kendall
Oyster Spatfall On Shellstrings In Virginia Rivers: 1973 Annual Summary, Dexter S. Haven, Paul C. Kendall
Reports
Although oyster setting levels in most Virginia river systems are still far below trose whicb commonly occurred prior to 1960, the 1973 season marked an improvement over the previous year when Tropical Storm Agnes raged througb the Chesapeake Bay region, creating adverse environmental conditions which were largely responsible_ for the_ lowest s},tting levels on record, Data for 1972,
Lower York River Dissolved Oxygen Study, Robert A. Jordan
Lower York River Dissolved Oxygen Study, Robert A. Jordan
Reports
Past studies of the lowerr York River have shown that dissolved oxygen (D .O.) concentrations decline in the summer months, occasionally falling one mg/ 1 near the bottom in deep water (Brehmer,1970; Jordan,1973) . Due to this apparently natural phenomenon the Virginia water quality standards for D.O. in estuaries (4.0 mg/1 allowable minimum, 5 .0 mg/1 minimum daily average, U.S.. E.P.A,1971), are not met during this period . Therefore additional waste-water discharges into the lower York River will not initiate violation of the standards, but may exacerbate the existing situation by extending the area and the time period affected by …
Acute Effect Of Free Chlorine On Selected Estuarine Invertebrates And Vertebrates : Final Report, Morris H. Roberts, Robert J. Diaz
Acute Effect Of Free Chlorine On Selected Estuarine Invertebrates And Vertebrates : Final Report, Morris H. Roberts, Robert J. Diaz
Reports
The objective of this project was to determine acute toxic effects of chlorine on selected estuarine organisms found adjacent to the projected outfall of a sewage treatment plant in the lower York River. The test species specified under contract were ovster (Crassostrea virginica) and clam (Mercenaria mercenaria) larvae, Acartia tonsa (a dominant copepod), and the fishes, menhaden (Brcvoortia tyranus), pipefish (Svngnathus fuscus), blennies (Hypsoplennius hentzi) and sheepshead minnow (Cyprinodon variegatus). The parameter of interest in the tests was mortality when the animals were exposed to a constant level of chlorine for a 48 or 96 hr period.