Assessing wetland climate change vulnerability for wetland management decision support using the hydrogeological landscape framework: application in the Australian Capital Territory

Abstract

The hydrogeological landscape (HGL) framework provides a landscape characterisation method that identifies areas of similar physical, hydrogeological, hydrological, chemical and biological properties, referred to as HGL units. The underlying principle of the HGL framework is that water distribution and movement is controlled by climate, landform, geology, regolith, soil and vegetation properties. By understanding the patterns of variability in the setting and controls of atmospheric, surface and groundwater systems for a given landscape, the developed HGL units, and associated landscape element-based management areas, can be used for hazard assessment and natural resource management centred on water availability, quality, sustainability and associated ecological systems. Existing wetland frameworks also demonstrate that it is the hydrogeomorphological or hydrogeological characteristics of the landscape that will determine the variability in water inputs and outputs for a wetland water balance, a principle shared with the HGL framework. It is therefore logical that HGL units and management areas can be used as planning units for wetland hazard assessment and management. This paper presents an assessment of climate change vulnerability for 1296 wetlands across the Australian Capital Territory using indicators representing current anthropogenic pressure, future ecological change and future hydrological change. The use of management areas for the hazard assessment allows understanding of the patterns of variability in the chosen indicators and hazard assessment outcomes specifically for the areas to be managed. This approach allows consideration of the landscape setting when identifying suitable locations to undertake on-ground management actions to address the hazards identified.