Spatiotemporal diversity, abundance and distribution of zoobenthos community of a temporary estuary in Kerala, India

摘要

Zoobenthic diversity of Veli-Akkulam Lake, a temporary estuary in Kerala, was assessed for the period from October 2008 to September 2010. The benthic macroinvertebrate community comprised of 17 species; categorized into Oligochaeta, Polychaeta, Crustacea, Chironomidae, Gastropoda and Bivalvia. Oligochaeta formed the most diverse group with six species included. The numerical abundance of zoobenthos during the study period varied from 951 to 1748 no.nr2 during 2008-09 and from 824 to 1856 no.nr2 during 2009-10 between different study locations. The highest abundance was observed at Station 3 in both the years, and the least was recorded from Station 2 during the first year and Station 1 for the second year. Chironomidae was found to be the most dominating group among the zoobenthos of the Veli-Akkulam Lake during the present study, comprising 38 of the total abundance. The overall deterioration of the water quality and eutrophication of the Veli-Akkulam Lake has resulted in decreased diversity ofzoobenthos. The most abundant groups were found to be chironomids and Tubifex sp., indicating the polluted nature of the water body.