Professor Bradley D Eyre BSc(Hons)(Adel) PhD(QUT) Research Interests: Estuarine and Coastal Biogeochemistry My initial work used simple mixing models, including the development of modified mixing models, to improve our understanding of the way nutrients are cycled in tropical and sub-tropical systems. The role of physical forcing events (i.e. floods) was emphasised in this early work (see Eyre, 2000). I then began focusing, in conjunction with my colleague Angus Ferguson, on the benthic metabolism of tropical and sub-tropical estuarine and coastal ecosystems. In particular, benthic carbon production and remineralisation and its link to nitrogen cycling processes such as benthic fluxes of inorganic and organic nitrogen, denitrification and N-fixation, and also the flow of carbon and nitrogen through lower food webs. I use a modified Membrane Inlet Mass Spectrometer (see Eyre et al., 2002) that allows us to measure direct 28N2 gas fluxes as well as 29N2 and 30N2 production following 15N additions allowing us to get simultaneous measurements of denitrification, N-fixation and net 28N2 gas fluxes. I received the 1999 Cronin Award by the Estuarine Research Federation (ERF) for my work on estuarine biogeochemistry. Whole Ecosystem Scale C. N and P Budgets I always had an interest in mass balance budgets as I see them as a way of constraining what we know, and what we do not know, about whole ecosystem scale flows of carbon, nitrogen and phosphorus. Budgets also provide a means of quantitatively comparing different coastal ecosystems. However, rarely do we have sufficient data sets available to construct these type of budgets (see Eyre and Mckee, 2002). Much of my estuarine coastal biogeochemical work is being undertaken in the context of providing information to fill data gaps in sub-tropical and tropical C, N and P budgets. And I will always go back to the budget framework when I have sufficient data sets. I have also been involved in LOICZ C, N, and P budgeting exercise having developed a number of budgets for Australian systems. Comparison of Tropical and Temperate Systems A common theme through much of my work is the comparison of tropical and temperate systems. I am interested in identifying the factors that modify the response of estuarine and coastal ecosystems from different climate zone to nutrient over-enrichment, in particular the role of benthic-pelagic coupling.
Journal articles
Carbon budgets for three autotrophic Australian estuaries: implications for global estimates of the coastal air-water CO 2 flux (with Damien Troy Maher), Global Biogeochemical Cycles: an international journal of global change (2012)
Estuaries are ‘hot spots’ in the global carbon cycle, yet data on carbon dynamics, in...
Coupling automated radon and carbon dioxide measurements in coastal waters (with Isaac RD Santos and Damien T. Maher), Environmental Science & Technology (2012)
Groundwater discharge could be a major, but as yet poorly constrained, source of carbon dioxide...
Denitrification and anammox in tropical aquaculture settlement ponds: an isotope tracer approach for evaluating N2 production (with Sarah A. Castine, Dirk V. Erler, Lindsay A. Trott, Nicholas A. Paul, and Rocky de nys), PLOS One (2012)
Settlement ponds are used to treat aquaculture discharge water by removing nutrients through physical (settling)...
Hypoxic events stimulate nitrogen recycling in a shallow salt-wedge estuary: the Yarra River estuary, Australia (with Keryn L. Roberts, Vera M. Eate, Daryl P. Holland, and Perran LM Cook), Limnology and Oceanography (2012)
The Yarra River estuary is a salt-wedge estuary prone to periods of stratification-induced anoxia and...
Influence of porewater advection on denitrification in carbonate sands: evidence from repacked sediment column experiments (with Isaac RD Santos and Ronnie N. Glud), Geochimica et Cosmochimica Acta (2012)
Porewater flow enhances mineralization rates in organic-poor permeable sands. Here, a series of sediment column...
Conference publications
Sediment biogeochemical indicators for defining sustainable nutrient loads to coastal ecosystems (with Angus JP Ferguson), Proceedings & presentations [electronic resource] / Coast to coast 2002, Australia's National Coastal Conference (2002)
Reports
Causes of deoxygenation in the Richmond River estuary, Final report to Environmental Trust (2001/RD/60005) (with Geoffrey Kerr and Leigh A. Sullivan), School of Environmental Science and Management Papers (2005)
Evaluation of the impact of nitrogen and phosphorous loads from the Alstonville, Wardell and Ballina sewage treatment plants on water quality in Richmond River catchment and estuary (with Peter R. Pepperell), School of Environmental Science and Management Papers (2001)
Nitrogen and phosphorous budgets for Tuggerah Lakes, Australia (with Peter R. Pepperell), School of Environmental Science and Management Papers (2001)
A physical classification of Australian estuaries (with M J. Digby, Peter Saenger, M B. Whelan, David McConchie, N Holmes, and Daniel J. Bucher), National River Health Program, Urban sub-program Report (1999)
The need for practical estuarine classification schemes as resource management tools is becoming more apparent...
Review of techniques to estimate catchment exports (with Rebecca A. Letcher, Anthony J. Jakeman, Wendy S. Merritt, Lester J. McKee, and B Baginska), School of Environmental Science and Management Papers (1999)
This Technical Report was commissioned by the NSW Environment Protection Authority as part of its...