Journal of the Marine Biological Association of India

Living foraminifera from a tidal creek at Pudimadaka, near Visakhapatnam, east Coast of India.

Volume 18 Issue 3

T. Venkata Rao and M. Subba Rao

Abstract

Core samples of sediments were collected during January, March, April, May, June, July, September and November, 1970 from stations located along the length of a tidal creek near Pudimadaka near Visakhapatnam, east coast of India. Samples of water just above the sediment surface were also collected and analysed for salinity and dissolved oxygen. During sampling of the sediments, the top one centimetre of the sediment core was removed and preserved in 5 % formaldehyde and later in the laboratory dead and living foraminiferal populations were differentiated using the Rose Bengal technique. Living foraminiferal populations were counted from a constant volume of the sediment. The sediments were analysed for grain size distribution and organic matter contents.

Ammonia beccarii. Ammonia beccarii var. tepida, and Quinqueloculina seminulum dominate among the calcareous species while Ammobaculites agglutinans, Textularia aggluttnans dominate among the arenaceous species.

Among several ecological factors that control the variety and abundance of living foraminiferal fauna, chlorinity of the waters appear to play a determining role in the area under study.

Date : 31-12-1976