Spatial relationship among phytoplankton abundance and physico chemical parameters around the coastal waters of Kerala

The phytoplankton abundance associated with hydrographical parameters at 28 selected stations (April 2012) of Kerala Coast have been discussed. Considerable variations were noticed both in magnitude and compositions in the phytoplankton density. In this investigation, a total 104 species of phytoplankton were identified and represents in different distinct class viz: Bacillariophyceae (78), Dinophyceae (22), Chlorophyceae (3), Cyanophyceae (1), and Dictyophycae (1). Diatom species were more prominent within the stations. However, Coscinodiscus species Asterionella species, Biddulphia species and Pleurosigma species were the common species found in almost all the stations and at station 25, blooming of Asterionella species were noticed. Compared to other stations, station 25 followed a high salinity and high silicate concentration. Nitrite showed a very slight increase whereas ammonia, nitrate and phosphate showed a complete depletion. The Phytoplankton population density depends upon the physico chemical parameters, and their intensity was mostly coupled with the parameters like salinity, pH, silicate and nitrite.