IMPACT OF ENVIRONMENTAL PARAMETERS ON POLYCHAETOUS ANNELIDS IN THE MANGROVE SWAMPS OF COCHIN, SOUTH-WEST COAST OF INDIA

Species composition, distribution and seasonal variation of polychaete fauna in the Cochin mangroves were evaluated. Effect of environmental parameters such as temperature, salinity, dissolved oxygen, pH, sedim ent texture and organic matter on the distribution of polychaetes was studied. Thirty three species of polychaetes belonging to 20 genera un der 10 families were identified. The errantia group were common than t he sedentaria. Correlation was observed between polychaete fauna and s alinity. Species diversity and richness was higher at st 1 (located ne ar the Cochin barmouth) during premonsoon and postmonsoon seasons.