Studies on the benthic fauna of Cochin backwater

Abstract

Studies on the macrofauna from the five selected stations spread over a distance of about 25 km in the Cochin backwaters showed that the benthic biomass was greater in the region which were near the sea The abundance of organisms decreased progressively towards the more estuarine zone The bivalves, gastropods and polychaetes were the most predominant forms in the sample The presence of larger bivalve, Meretrix ovum and the polychaete, Diopatra neopolitana at the stations near the sea considerably increased the benthic biomass at these stations Organisms of lesser importance were crabs, fish, ophiuroids and sea anemones Studies on meiobenthos which was restricted to the estuarine zone only showed a high degree of abundance of foraminifera and nematodes Areas of high salinity in the backwater are those which are rich in nutrients and chlorophyll and were found to support a denser benthic population