Zinc and iron cycling in the north and south Tasman Sea

Over the last decade studies have confirmed the key role of iron plays in controlling many aspects of phytoplankton physiology, community structure and ecology. The biogeochemical cycling of iron in the upper ocean involves many complex interactions between its chemistry, photochemistry and the microbial foodweb. Like iron, zinc is a key element for phytoplankton growth. 

Zinc is the central atom in the metalloenzyme carbonic anhydrase which is used by phytoplankton to regulate the uptake of bicarbonate from seawater. Laboratory culture experiments have shown that the concentration of zinc in open-ocean waters is potentially low enough to limit the growth of certain species of phytoplankton. 

The aim of this project is to determine iron and zinc concentrations across a range samples collected from the Tasman Sea region and then determine the chemical speciation of these two elements in preserved samples. (Collaborator: Phil Boyd - NIWA, NZ)