An overview of dinoflagellate cysts in recent sediments along the west coast of India

Abstract

Distribution and abundance of dinoflagellate cysts in recent sediments along the west coast of India (26 coastal stations and 3 ports) is presented. A total of 47 different types of cysts and a maximum abundance of 1076 cysts g^–1 dry sediment were recorded. Highest cyst abundance was recorded at coastal station Mangalore (801 cysts g ^–1 dry sediment) and Kochi port (1076 cysts g^–1 dry sediment). Lowest cyst abundance was observed at coastal stations from Kochi to Trivandrum. This difference may be attributed to the composition of sediment, since sandy stations had lower abundance and diversity of cysts. Heterotrophic dinoflagellate cysts, mainly <i style="">Protoperidinium </i>species, were the most diversified, predominating at most of the stations sampled. Cysts of potential Harmtul Algal Bloom (HAB) species capable of forming blooms were also detected in the sediment. Effect of the environmental settings of the study area such as upwelling, South West monsoon and anthropogenic pressures on the dynamics of these HAB species in Indian waters needs to be elucidated.