Vallentine Annexe (H22)
BSc, Geology, Univ. Adelaide (1995), BSc (Honours), Soil Science, Univ. Adelaide (1996), PhD, Soil Science, Univ. Adelaide (2002)
2002-2005: French Atomic Energy Commission, Saclay, France.
2005-present: UNSW Australia, School of Civil and Environmental Engineering (UNSW Water Research Centre)
Coastal Lowland Acid Sulfate Soils
I conduct applied research into managing the environmental impacts of coastal acid sulfate soils in northern NSW with the Tweed Shire Council, NSW Cane Growers’ Association and NSW Milling Cooperative. The main research drivers are to: 1) identify acid sulfate soil hotspots within catchments; 2) devise site-specific land/drain modifications to limit acid sulfate soil problems, but maintain agricultural profitability and; 3) monitor how successful these modifications have been. Some of the practicable outcomes from this research can be viewed at the Tweed Shire Council website (http://www.tweed.nsw.gov.au/Agriculture) or accessed through UNSWorks.
My current main interest in this area is to improve nitrogen-fertiliser efficiency and limit off-site gaseous and aqueous nitrogen losses from these unique soils resulting in a win-win for farmers and the environment.
The main aim of this research is to be able to predict how materials used to contain or remediate pollution will perform in ‘real life’. The two main materials I work with are nanoscale zero-valent iron (nZVI) and smectite clay minerals. Of particular interest is discovering how the redox reactions involving these materials lead to the degradation of organic, or the immobilization of inorganic, contaminants.
In many coastal and floodplain sediments the Fe(II)/Fe(III) redox couple exerts a strong influence on the cycling of many desirable elements, such as nitrogen and carbon, but also toxic metals like uranium. This research takes a fundamental approach to identifying how we can manipulate the iron redox cycle to obtain benefits such as increasing the lifetime of soil organic carbon, reducing nitrous oxide emissions, recovering essential nutrients from wastewaters and mitigating the effects of metal pollution.
My interest in uranium geochemical processes ranges from the generation of detailed (bio)geochemical knowledge that could increase metal extraction efficiencies for the mining industry to redox processes that can reduce the mobility of uranium at contaminated sites.