Nannoplankton from the Bombay-Saurashtra continental shelf of India: An appraisal using cluster analysis

Abstract

Nannoplankton data from 28 stations in the northwestern continental shelf of India was subjected to Q-mode cluster analysis. Two biotopes A and B were identified. Although, Gephyrocapsa oceanica was by far, the most abundant species in both the clusters, the most striking feature of the biotope A was the total absence of Braarudosphaera bigelowi, Syracosphaera pulchra and Thoracosphaera sp. while the biotope B was represented by all the 12 species identified. The study indicates that oxygen and to some extent calcium-carbonate plays an important role in the distribution of nannoplankton assemblages in the area