Quantitative distribution of meiobenthos in the Gulf of Martaban, Myanmar Coast, north-east Andaman Sea

Abstract

Quantitative distribution of meiofauna in the depth range 20 to 1000 m of the Gulf of Martaban, Andaman Sea was studied from 46 stations during a synaptic survey carried out in April-May 2002 of ORV Sagar Kanya Cruise SK175. Fauna was dominated by three taxa: free living nematodes (80%) benthic copepods (5.9%) and foraminiferans (2.8%). Other groups together contributed more than copepods in total abundance. Total density ranged between 40 and 612/10 cm² and dry weight biomass from 0.21 to 0.428 mg/10 cm² in different sediment type and depth zone. Numerical abundance of meiofauna was high in fine silty clay and low in sandy bottom. Formation of three main clusters suggests the influence of dominant sediment texture of clayey sand sand silt clay, silty-clay clayey-silt, and sandy substratum. Fauna was contagiously distributed except at few stations where the distribution was regular.

Meiofauna of the present study were similar to those of Andaman Sea and Bay of Bengal and the density changes appears to be related to hydrographic condition and sediment characteristics of the region.