Phytoplankton pigments and primary production around the oil fields off Maharashtra

Abstract

Studies on phytoplankton pigments, primary productivity and particulate organic carbon were made at 21 locations off Bombay (Maharashtra, India) and adjacent waters during the 48th cruise of @iORV Sagar Kanya@@ in December 1988 to January 1989. Variation in chlorophyll a at surface was from 0.3 to 48.6 mg@u-3@@ whereas at the subsurface the range decreased to 0.3 - 9.1 mg m@u-3@@. The respective ranges in primary productivity at surface and subsurface were 0.4 - 146.9 and 0.04 - 16.4 mgC m@u-3@@ day@u-1@@. Highest column production (276.8 mgC m@u-2@@ day@u-1@@) was recorded in the coastal water off Bombay while lowest rate (12.1 mgC m@u-2@@ day@u-1@@) was observed at the outer zone. The ratios of chlorophyll a to phaeophytin were fairly high at the stations located away from the oil fields whereas the same decreased noticeably at the stations around the oil fields and coastal waters of Bombay suggesting the unhealthy condition in these areas