Seasonal shifts of meiofauna community structures on sandy beaches along the Chennai coast, India

Abstract

Meiofauna standing stocks and community structures were studied at five sandy beaches along the Chennai coast of the Bay of Bengal, at the SE coast of India from January 2000 to February 2001. Meiofauna densities ranged from 1341.14 ± 1205.76 ind. 10 cm-2 to 3.73 × 106 ± 4.1 × 105 ind. 10 cm-2. Mean abundance was highest during February 2000 (35 565.85 ± 12 463.03 ind. 10 cm-2) and lowest during March 2000 (11 465.85 ± 4250.26 ind. 10 cm-2). As for individual stations, the highest abundances were found at Neelangarai (67 058.31 ± 7153.43 ind. 10 cm-2) and lowest at Marina (52 517.69 ± 5373.63 ind. m-2), respectively. As for taxa, the mean of the highest and lowest meiofauna abundance was observed in Copepoda and Cladocera during different months (109 372.29 ± 10 906.42 ind. 10 cm-2 and 1341.14 ± 241.15 ind. 10 cm-2) and at different stations (30 6242.40 ± 3905.26 ind. 10 cm-2 and 3755.20 ± 88.90 ind. 10 cm-2), respectively. Cluster analysis and principal component analysis showed that the elements of the meiofauna were separated into three major groups according to their distribution and abundance. Correspondence analysis showed the importance of meiofauna abundance with different months and stations. Ecological indices varied with month, station, and with meiofauna group. Monthly changes in the nematode-copepod index showed that both Ernavoor and Thiruvotriyur were more subjected to pollution, with the highest diversity and evenness values for nematodes among all stations.