Biological, chemical and physical observations in inshore waters of the Great Barrier Reef (1975-1978)

A routine sampling program was run over three consecutive years (1975-78) at fixed field stations on a transect from the Townsville Harbour to Keeper Reef, an inner reef in the Great Barrier Reef complex. From December 1975 to December 1976, bi-weekly sampling was conducted at three stations as part of a phytoplankton productivity program, which initially included a further 7 stations. Parameters measured were temperature, salinity, transparency, phytoplankton pigments and net zooplankton.From January to December 1977 the sampling program continued at approximately weekly intervals, adding new measurements for microzooplankton, nutrients (nitrate, nitrite, ammonia, phosphate and SiO3) and particle size distribution in seawater. The sampling program up to the end of 1977 was aimed at evaluating the horizontal gradient of various biological, chemical and physical properties, so that only surface samples were consistently taken. From January to December 1978, the detailed vertical structure of the water column was investigated at Station 2. Dissolved oxygen, particulate organic carbon, dissolved organic nitrogen and phosphate (the last two items from August) were added to the items previously measured. This research was undertaken to extend the limited knowledge of the biological, chemical and physical properties of inshore waters of the Great Barrier Reef. The purpose of the initial study, which commenced in 1975, was to establish the general patterns of phytoplankton ecology in the GBR environment and to evaluate the presence or absence of a seasonal cycle.