Development and case studies: Risk assessment and decision making framework for managing groundwater dependent ecosystems with declining water levels
This research developed and validated a risk assessment and decision-making framework for managing groundwater dependent ecosystems with declining water levels due to climate change and other causes.
The objective of this research was to develop and test a risk assessment and decision-making framework for managing groundwater dependent ecosystems (GDEs) with declining water levels due to climate change, anthropogenic extraction, land use and land management. The framework was developed by a multidisciplinary team of ecologists, modellers and hydrogeologists in south-western Australia, a biodiversity hotspot that has already suffered three decades of below average rainfall and consequently declining groundwater levels due to increased groundwater abstraction and land use change. This has provided a ‘living experiment’ providing validation of the framework against observed changes (not just modelled projections). The combination of this research together with input from a suite of end-users, other scientists and experts from across Australia has provided a robust and adaptable framework.
The report outlines how the framework was developed and tested on three different types of GDEs: surface expression of groundwater in 1) wetlands on the Gnangara Groundwater System in Perth and 2) the Blackwood River, and 3) the subterranean expression of groundwater in the Leeuwin Naturaliste Ridge Cave System. However, the framework could be adapted to any type of GDE or surface water system.
The framework integrates a standard risk assessment protocol enabling the approach to be easily transferred to sites within Australia and internationally. The framework is based around the construction of a conceptual model which identifies the interrelationships between climate, hydrology, water quality and/or biotic resources and the biota in an ecosystem. Before the framework is undertaken, management issues are identified and the site is characterised in terms of the type of GDE, its spatial extent, hydrogeology and assets within the site location. The framework then proceeds through five steps: identify the hazard, determine the exposure and vulnerability of the GDE, assess the effects of the hazard, characterise risk and then manage the risk. A suite of tools are provided by this framework for managing risk and climate change adaptation including: the identification of hazards and their cause(s), exposure and vulnerability of GDEs to hydrological stress, key drivers that cause ecosystem change, thresholds of tolerance of the biota for these key drivers, conceptual models, and risk assessment and decision-making tools in the form of Bayesian Belief networks and spatial models of risk.
Please cite this report as:
Chambers, J, Nugent, G, Sommer, B, Speldewinde, P, Neville, S, Beatty, S, Chilcott, S, Eberhard, S, Mitchell, N, D’Souza, F, Barron, O, McFarlane, D, Braimbridge, M, Robson, B, Close, P, Morgan, D, Pinder, A, Froend, R, Horwitz, P, Cook, B & Davies, P 2013, Adapting to climate change: A risk assessment and decision making framework for managing groundwater dependent ecosystems with declining water levels. Development and case studies, National Climate Change Adaptation Research Facility, Gold Coast, 100 pp.
View the supporting documents in this report suite:
Assessing risks to groundwater dependent wetland ecosystems in a drying climate
Identifying thresholds for responses of amphibians to groundwater and rainfall decline
Environmental variables in the habitats of south-western Australian freshwater fishes
The impacts of declining water levels on stygofauna communities
Development of Bayesian Belief Networks for modelling the impacts of falling groundwater
Spatially representing the impacts of falling groundwater
This photo is copyright © Vasse Wonnerup Estuary, Western Australia (Krysztof Wienczugow, Marine and Freshwater Research Laboratory, Murdoch University).