MACROBENTHIC ASSEMBLAGE AND UTILITY OF DIVERSITY IN ASSESSING THE HEALTH OF AN ECOSYSTEM, SOUTHEAST COAST OF INDIA
G. Ponnusamy, M. Pravinkumar, K. Sundaravarman, C. Viswanathan and K. Kathiresan
Abstract
Present observation investigates the diversity and seasonal variations of benthic macrofauna and associated environmental parameters influencing the benthic community in the coastal waters of southeast Indian coast. Four seasonal collections were made from January - 2013 to December – 2013, such as, post-monsoon, summer, pre-monsoon and monsoon in the inshore waters of Thiruchendur, Tuticorin and Vembar coastal region of Southeast India. Altogether, 36 infaunal samples (Peterson grab 0.256 m2) were collected which revealed the occurrences of 86 species representing five diverse groups. Polychaetes were the dominant group (58.67%), followed by Amphipods (10.67%,), Isopods (10.67%,). Bivalves (8%) and Gastropods (8%). Diversity (H’log2) ranged between 3.623 (station 3, monsoon) and 4.176 (station 2, summer). Cluster and MDS plots drawn showed that stations of Vembar, Tuticorin and Thiruchendur formed group among themselves indicating dissimilarity in their faunal composition and its abundance. Some polychaetes were abundant more than other species i.e.g., Lumbrineris sp., Cossura coasta, Capitella capitata, Pisionidens indica and Arabella mutans, in station 3 (Tuticorin) as they indicate the pollution of water due to the industrial and active harbor discharging their waste to the marine environment