Phytoplankton Groups in the Estuarine Mangrove Creeks of Edakochi (Kerala), Southwest Coast of India: A Preliminary Study

Abstract

The present work focused on the ecological studies in the mangroves of the Edakochi region, Kerala (India)with special reference to phytoplankton groups. This wetland is situated on the banks of Vembanad Lake,the largest Ramsar site of Kerala. Sampling was carried out from February to June 2017. 5 true mangrovespecies and 2 semi- mangrove species were noted from the Edakochi region. A total of 25 phytoplanktonspecies were recorded from different stations comprising 15 species of Bacillariophyceae, 7 species ofDinophyceae, 1 species of Cyanophyceae, 1 species of Chlorophyceae and 1 species of Ciliateae. In eachstation the species composition was found in an order of Bacillariophyceae > Dinophyceae >Cyanophyceae> Chlorophyceae >Ciliatae. Bacillariophyceae contributed 60% of the species, whereas Dinophyceaecontributed 28%. Cyanophyceae, Chlorophyceae and Ciliateae contributed 4% each. The highest numberof species (19) was recorded during March and the highest cell density was recorded during April (1143/l). The lowest cell density was recorded in June (844/l). From the study results, it was noted that the highestnumber of species in March was due to the favorably increased salinity. The shift in the salinity regime maybe the reason for the lowest number of species in June. Alternation in species diversity influences variousecosystem phenomenon, such as nutrient retention, primary productivity and vegetation dynamics. Thestudy findings depict good species diversity of phytoplankton in the Edakochi mangrove ecosystem.