Assessing the importance of nitrogen fixation to temperate, intertidal embayments using stable isotopes

The overall health and productivity of many marine environments is commonly thought to be controlled by the biological availability of nutrients such as nitrogen. This thesis has quantified the importance nitrogen fixation to two embayments in south-eastern Australia, Western Port and Port Phillip Bay. Nitrogen fixation is a mechanism through which biologically available nitrogen can be produced, and it was found that this represented a significant source of nitrogen (31 – 47% of total inputs) compared to other sources such as rainfall and riverine inputs.