An investigation on the phytoplankton dynamics from the coastal waters of New Mangalore Port, Southwest coast of India

Abstract

Phytoplankton species composition and distribution in relation to environmental parameters was investigated from the inshore and coastal waters of New Mangalore Port. A total of 16 stations were selected in such a way that 3 were inside the port and 13 in near shore coastal waters. Water quality parameters such as temperature, salinity, pH, dissolved oxygen along with nutrients such as nitrate, phosphate and silicate were monitored; along with phytoplankton biomass (chlorophyll a) and species composition. Chlorophyll a ranged between 0.01 and 4.95mgm^-3 among the stations. The qualitative and quantitative assessment of phytoplankton was carried out separately for all the stations. Phytoplankton community was mainly dominated by diatoms (63%), followed by dinoflagellates (24%), blue green algae (2%), and silicoflagellates (2%) in their order of descend. The present study infers that in addition to other factors, small scale hydrographic changes affect the composition of the phytoplankton community. Several factors were tightly coupled, high species diversity, increased diatom and dinoflagellates abundances, and Chl a. In this study seem more apparent at higher taxonomic levels (diatoms and dinoflagellates).