Life Sciences Commons^™

The Effects Of Varying Fresh Water Discharge On Dispersion In An Estuarine Hydraulic Model Of The Lafayette River, Norfolk, Virginia, Michael J. Jugan

OES Theses and Dissertations

Three experimental tests were conducted in the Lafayette River branch of the Chesapeake Bay Hydraulic Model, each successive test with an increase in the amount of fresh water discharged into the head of the river. This was done to study the response from varying river discharge on mixing parameters including the longitudinal dispersion coefficient (E).

The model generated a tide of constant range and period. Batch releases of Rhodamine WT dye were made in the model and sampled throughout the river for ten tidal cycles. Samples were taken simultaneously at selected high and low water slack.

The calculation of the …

The Effects Of Kepone On The Estuarine Copepod Acartia Tonsa, Judith Marie Wilson

Biological Sciences Theses & Dissertations

Due to the contamination of a 113 km reach of the James River, Kepone poses a serious environmental threat to the Chesapeake Bay. The purpose of the study is to determine the acutely toxic and sublethal levels of kepone for the copepod Acartia tonsa, and to investigate what effects those levels may have on filtration rates.

Kepone was determined to be acutely toxic to A. tonsa, with a 96 hour LC50 of 4.96 ug/1. Dunaliella tertiolecta was selected as the food source for the grazing experiments. Kepone concentrations of 0.046 ug/1 significantly (0.05 level) reduced the flltering rate …