PELAGIC PRIMARY PRODUCTION IN THE CORAL AND SOUTHERN SOLOMON SEAS

Phytoplankton primary production was measured around the periphery of the Coral Sea during October 1985 and in the boundary current systems bordering the northern Australian Great Barrier Reef (GBR) and Papuan Barrier Reef (PER) during October 1985 and June-July 1988. Under stron g wind conditions (mean winds 8-12 m s(-1)), the north-western Papuan Barrier Reef region was characterized by a shallow surface mixed layer , shallow nutriclines (25-75 m) and shallow subsurface chlorophyll max ima. Under low wind stress conditions (mean winds <5 m s(-1)), the sou thern and western Coral Sea were also characterized by a shallow surfa ce mixed layer and stable underlying density profiles but deep (>100 m ) nutriclines and deep (60-125 m) subsurface chlorophyll and primary p roduction maxima. Regardless of location, most primary production occu rred above the 20% mid-day isolume surface. Phytoplankton standing cro p and primary production in all regions were dominated by picoplankton (<2-mu m size fraction). Very high primary production rates (1-3 g C m(-2) day(-1)) were measured at a number of stations adjacent to the w estern margin of the PER and within the central basin of the Louisiade Archipelago. Evidence for upwelling along the western margin of the P ER was observed under both north-easterly (normal to the reef axis) an d south-easterly (parallel to the reef axis) wind regimes; however, su rface outcropping of upwelled water did not occur. Oceanic primary pro duction in the Coral Sea is estimated to be between 100 and 200 g C m( -2) year(-1). Primary production in and around the Louisiade Archipela go appears to be on the order of 200-300 g C m(-2) year(-1). Nearsurfa ce chlorophyll standing crop was generally better correlated with near -surface primary production than was total chlorophyll with total area l primary production.