A pilot study to demonstrate the use of 15N tracers for determining the flow of nitrogen through lower food webs
Funding: ARC Discovery 2006-2007
Investigators: Bradley Eyre (SCU), Joanne Oakes (SCU), Jack Middelburg (NIOO)
Background / Summary:
Management of nitrogen enrichment, and protection of biodiversity in Australia’s coastal waters are likely to cost hundreds of millions of dollars over the next ten years. Understanding the role that organisms at all levels play in the functioning of coastal ecosystems is a crucial step towards protecting and effectively managing coastal environments. This project demonstrated the ability of stable isotopes (specifically, 15N) to trace the flow of nitrogen through the lower food web. Components of the study investigated nitrogen incorporation and transfer by bacteria and fauna in intertidal and subtidal sediments, and compared bacterial assimilation and transformation of nitrogen derived from native seagrass (Zostera capricorni) and an introduced algae (Caulerpa taxifolia). Stable isotope tracers are a powerful technique for determining how organisms from bacteria to macrofauna affect the functioning of coastal systems. Increased understanding of ecosystem functioning, will inform management, rehabilitation and protection of waterways (including biodiversity) in Australia.
Labelling an intertidal plot with 15N in the Brunswick Estuary (sub-tropical)
Relevant Publications
Veuger, B., Eyre, B.D., Maher, D., Middelburg, J.J. (2007) Nitrogen incorporation and retention by bacteria, algae, and fauna in a subtropical intertidal sediment: An in situ 15N-labeling study. Limnol. Oceanogr. 52(5):1930-1942
Updated: 21 December 2010