European Journal of Biomedical and Pharmaceutical Sciences

COMMUNITY STRUCTURE OF BENTHIC FORAMINIFERA IN THE POONTHURA ESTUARY, THIRUVANANTHAPURAM, KERALA

*K. S. Anila Kumary

ABSTRACT

The present investigation reveals the spatio-temporal variations in the distribution, abundance and diversity of benthic foraminifera in the Poonthura estuary (latitude 8025’ - 8030’N and longitude 76055’- 770 00’E) on the southwest coast of India lying in the outskirts of Thiruvananthapuram, the capital city of Kerala. Sediment samples were collected from 3 stations in the Poonthura estuary and totally 108 core samples were collected in order to study the assemblages of foraminifera. Density of total foraminifera (No/m2) in the estuary seasonally varied from 144 to 422. Upstream stations were poorly populated while middle and downstream stations have a large population. Foraminiferal species richness was very low, only 12 species were identified. Among the different foraminiferal species Ammobaculites catenulatus, Textularia agglutinans, Textularia sagittula and Ammonia becarii are found wide spread and abundant. Preferences for substrate type coupled organic enrichment and higher salinity conditions explain for the occurrence of benthic foraminifera in the Poonthura estuary.

Keywords: Benthic foraminifera, Poonthura estuary, Species diversity.