Factors controlling summer phytoplankton production in greater Cook Strait, New Zealand

Abstract

An intensive study was made of greater Cook Strait in the summers of 1980 and 1981 to determine the availability of dissolved inorganic nutrients in surface waters and the influence this may have on phytoplankton production. Phytoplankton biomass in greater Cook Strait appears to be controlled mainly by zooplankton grazing and turbulence or advection. The relative influence of factors governing primary production on phytoplankton distribution was assessed for the tidal mixing area off Marlborough Sounds, Manawatu River water, the Kahurangi Point to Cape Farewell upwelling region, and eastern Cook Strait.

Keywords:

• Cook Strait
• New Zealand
• upwelling
• tidal mixing
• phytoplankton
• chlorophyll a
• primary production
• temperature
• salinity
• nitrate
• nutrients

Notes

Present address: Fisheries Management Division, Ministry of Agriculture and Fisheries, P. O. Box 3437, Auckland, New Zealand