Diurnal cycle of water temperature and water quality in a littoral zone of a eutrophic lake

The role of convective circulatin in ecosystems in a brackish lake

Abstract

We have conducted a continuous measurement of temperature and water quality in a littoral zone of a brackish lake, Lake Shinji, where filter-feeding bivalves (Corbicula japonica) are densely populated. Daytime heating and nighttime cooling created density gradients that drove strong horizontal mass exchange. Simultaneous measurement of Chlorophyl a. concentration suggests that this circuration, especially during cooling period, mainly supports feeding of phytoplankton by bivalves which are habited at the lake bottom, and thus controls natural purification process through benthic-pelagic coupling.