Phytoplankton pigments and macrobenthos in nearshore waters off an oil terminal at Uran (Maharashtra), west coast of India

Significant temporal and tidal variations of chlorophyll a (2.1-11.8 mg m(- 3)) were noticed. Chlorophyll a was less during low tide (av. 3.8 mg m(-3)) as compared to high tide (av 8.1 mg m(-3)). The predominance of Nitzschia closterium, Skeletonema costatum and Melosira sulcata especially during ebb suggested their tolerance to petroleum wastes. The Rocky intertidal zone s howed higher macrofaunal density at the upper zone (av 6992 m(-2)) as compa red to lower zone (av 1373 m(-2)) whereas the biomass was comparable betwee n the two zones. The subtidal regions had poor faunal group diversity, faun al density (av 250 m(-2)) and biomass (av 0.2 gm(-2)) associated with claye y silt bottom enriched with organic matter (3.3%). The subtidal fauna and s ediment quality indicate a reducing trend in macrofaunal population and bio mass over a period of 8 years.