Studies on the effects and the accumulation of mercury on phytoplankton of Par Pond, Savannah River Plant, Aiken, South Carolina. Final report

Studies on the synergistic effects of mercury and temperature on the phytoplankton of Par Pond showed that there was a synergistic effect on production when the organisms were shocked with warm or cold water. When the phytoplankton were transferred from cold to hot, production increased without mercury, while the phytoplankton exposed to mercury were inhibited. Other studies were conducted on the uptake and accumulation rates of mercury at various mercury concentrations; results are shown by means of graphs. Studies were conducted to determine the effects of HgCl/sub 2/ on the photosynthetic rates of phytoplankton and the growth and reproductive rates of selected cultured species of phytoplankton as influenced by the concentration of the mercury in the media, the concentration of cells and stage of the growth cycle upon exposure to the mercury, and the duration of exposure to mercury. Organisms used were the dinoflagellate, Amphidinium carterae, and the diatom, Skeletonema costatum. The effects of mercury and temperature interactions on the growth of phytoplankton were studied using three species of algae. Synura petersenii was severely inhibited by mercury in all experiments. When Chlamydomonas sp. was subjected to mercury at 30/sup 0/, growth was severely inhibited. Growth of Nitzschia sp. was enhancedmore » at 15/sup 0/ when temperature shock was followed by mercury addition. (HLW)« less