Distribution and controlling mechanisms of primary production on the Louisiana-Texas continental shelf

The northwest Gulf of Mexico is marked by strong seasonal patterns in regional and mesoscale circulation and variable effects of riverine/estuarine discharge, which influence distributions of nutrients, phytoplankton biomass and primary production. Relatively high biomass and primary production were observed in inner shelf waters during spring conditions of high river discharge. During summer, when surface currents shifted towards the north and east, values of nutrients, biomass and primary production were relatively high east of Galveston Bay and decreases outward from the coast. The findings demonstrate that the interaction of circulation and availability of light and nutrients are largely responsible for variations in primary production.