Journal of the Marine Biological Association of India

Vertical distribution of microphytobenthos in Cochin estuary

Volume 51 Issue 1

M. G. Sanilkumar, A.V. Saramma and K. J. Joseph

Abstract

Microphytobenthos or benthic microalgae are recognised as the dominant flora in the littoral zone,estuaries and other shallow aquatic ecosystems. A preliminary study on the vertical distribution of microphytobenthos was carried out for a period of 13 months (2005-2006) at a selected station in Cochin estuary. Their distribution, biomass as chlorophyll a and community structure were investigated. Microphytobenthos included 27 species of diatoms and 5 species of blue-green algae. Pennate diatom,Amphora turgida Gregory, is a new distributional record from India. Both qualitative and quantitative distributions of flora along the vertical zone upto a depth of 5 cm were studied. During monsoon months, benthic chlorophyll a was lower than that of the planktonic counter part and was higher during late postmonsoon and premonsoon. The planktonic and benthic chlorophyll a showed lowest concentrations during June-July. The ratio of phaeopigment to chlorophyll a was found to be < 0.3 indicating an actively growing microflora with very low grazing pressure.

Keywords

Microphytobenthos, vertical distribution, Cochin estuary

Date : 01-09-2009