Variation of water quality in Chilika lake, Orissa

Abstract

The water quality parameters such as pH, salinity, DO, BOD, PP, nutrients (NH3-N, NO2-N, NO3-N, PO4-P, Total P), and chlorophyll a, b and c, were studied for the entire Chilika lake from 1998 to 2001 covering a maximum of 23 sampling stations. The pH of water was alkaline throughout the lake and both pH and salinity varied widely. Higher pH with low salinity zones reflected disintegration of submerged weeds. Correlation analysis supported the increase of pH, high photosynthetic activity, high nutrients as well as phosphate depletion due to phytoplankton utilization in the fresh water zone. The opening of a new mouth during the study period helped subsequently to bring rise to salinity throughout the lake re-ion, flush out sediment load from lake, disintegrate weeds, increase biodiversity etc., which would ultimately enhance the fish, prawn and crab catch.