The anticipated impacts of climate change are warmer conditions, an increasing proportion of rainfall to occur from heavy falls, increasing occurrence of drought in many regions, increasing frequency of intense tropical cyclones, rising sea levels and frequency of extreme high seas (e.g. storm surges). All of these predicted impacts have direct relevance to coastal acid sulfate soils landscapes, through either exacerbating sulfide oxidation by drought, re-instating reductive geochemical processes or changing the export and mobilisation of contaminants. The interaction of specific land management factors such as man-made drainage will also have a significant role in how the predicted impacts of climate change affect these landscapes.
Understanding the potential impacts of climate change for coastal lowland acid sulfate soils is particularly important, given the utility of these areas for agriculture and urban communities, their unique capacity to cause extreme environmental degradation, and their sensitivity to climatic factors such as temperature and hydrology and susceptibility to sea-level inundation.
There is a strong and expanding fundamental knowledge of processes in coastal acid sulfate soils, but limited studies to date that consider the impacts of climate change. Using data from our research group this paper examines some of the key issues of climate change of relevance to acid sulfate soil. We investigate the hydrogeochemical consequences of seawater inundation of an 800 Ha acid sulfate soil wetland and study of current drought triggered broad-scale oxidation (i.e. 20, 000 Ha of exposed soils) of lake bed sediments in the lower Murray-Darling River Basin, South Australia.