Journal d'écosystème et d'écographie

Abstrait

Impact of Water Quality on Species Composition and Seasonal Fluctuation of Planktons of Batticaloa lagoon, Sri Lanka

Harris J.M* and Vinobaba P

This study examines whether planktons of the Batticaloa lagoon could be considered as bio-indicator of areas subjected to various anthropogenic and geomorphologic influences. However the physico-chemical parameters of the lagoon plays vital role in supporting the existence of biological parameters. This study was carried out for planktonic survey and in situ measurement of existing hydrological physico-chemical parameters from 9th July 2008 to 22nd June 2009 over the wet and dry seasons on seven sampling points of the Batticaloa lagoon. Comparatively, a higher number of species was recorded in the dry than in the wet season but there was little variation in species composition with respect to seasons. The compositions of phytoplankton were dominated by Bacillariophyceae which contributed about 55.81% to the total phytoplankton density. Nitzschia sp and Navicula sp lack seasonality and hence observed in both seasons. The 2 holoplankton groups of species increased in abundance during the wet season, while about 4 species lacked seasonality. Few phytoplankton species were reported to be potentially harmful/toxic bloom species. The information and observation in this study will be very useful in formulating management policies for the future of the Batticaloa lagoon.