Assessment of seasonal variation in distribution and abundance of plankton and ichthyofaunal diversity in relation to environmental indices of Karankadu Mangrove, South East Coast of India.

Karankadu mangrove situated along the Southeast coast of India is known for its unique and extreme species diversity and richness. Ecological functions of this mangrove comprise of nutrient cycling, coastal protection, fish fauna production and carbon sequestration besides providing livelihood to nearby coastal communities. The current study having assessed seasonal fluctuations of various Physico-chemical factors viz., rainfall, pH, surface water temperature, salinity, dissolved nutrients in the water and sediments, primary productivity and plant pigments (chlorophylls a,b,c) during the study period from July 2018 to June 2019, recorded a total of 29 species of zooplankton, 26 species of phytoplankton, and 19 species of fish with observed maximum density at summer and pre-monsoon period of the year. Relationship between the biotic and abiotic components of the ecosystem from the baseline data collected, was established through the statistical analysis performed.