Phytoplankton distribution and production in Port Hacking Estuary, and an empirical model for estimating daily primary production

Abstract

The variations of phytoplankton biomass with both time and space are described for Port Hacking, New South Wales, a marine-dominated estuary. Frequent short-term increases in phytoplankton biomass and production were caused by estuarine hydrological events resulting in the release of regenerated nutrients, and by coastal hydrological events where slope-water intrusions enriched the coastal waters and were introduced into the estuary by tides. These frequent changes prevented any prediction of primary production. A simple empirical model was devised to estimate daily primary production by phytoplankton from measurements of phytoplankton biomass, total daily solar irradiance, and light attenuation by the water column.