Bardsley D.K.,University of Adelaide |
Sweeney S.M.,Land and Biodiversity Conservation
Environmental Management | Year: 2010
Climate change has the potential to compromise the sustainability of natural resources in Mediterranean climatic systems, such that short-term reactive responses will increasingly be insufficient to ensure effective management. There is a simultaneous need for both the clear articulation of the vulnerabilities of specific management systems to climate risk, and the development of appropriate short- and long-term strategic planning responses that anticipate environmental change or allow for sustainable adaptive management in response to trends in resource condition. Governments are developing climate change adaptation policy frameworks, but without the recognition of the importance of responding strategically, regional stakeholders will struggle to manage future climate risk. In a partnership between the South Australian Government, the Adelaide and Mt Lofty Ranges Natural Resource Management Board and the regional community, a range of available research approaches to support regional climate change adaptation decision-making, were applied and critically examined, including: scenario modelling; applied and participatory Geographical Information Systems modelling; environmental risk analysis; and participatory action learning. As managers apply ideas for adaptation within their own biophysical and socio-cultural contexts, there would be both successes and failures, but a learning orientation to societal change will enable improvements over time. A base-line target for regional responses to climate change is the ownership of the issue by stakeholders, which leads to an acceptance that effective actions to adapt are now both possible and vitally important. Beyond such baseline knowledge, the research suggests that there is a range of tools from the social and physical sciences available to guide adaptation decision-making. © 2010 Springer Science+Business Media, LLC.
Souter N.J.,Land and Biodiversity Conservation |
Watts R.A.,Land and Biodiversity Conservation |
White M.G.,Land and Biodiversity Conservation |
George A.K.,Land and Biodiversity Conservation |
McNicol K.J.,Land and Biodiversity Conservation
Ecological Indicators | Year: 2010
A conceptual model describing the response of two Australian floodplain eucalypts, river red gum (Eucalyptus camaldulensis) and black box (Eucalyptus largiflorens), to changes in water availability was developed based on field observations. This model was incorporated into a percentage based visual method estimating two tree crown parameters, crown extent and density. Extent is the amount of foliage at the periphery of the assessable crown; density is the density of assessable crown foliage. Polychoric correlation was used to determine the level of agreement between two experienced observers assessing river red gum and black box trees using a simple percentage scale and a percentage scale supported by the conceptual model. Trees were evaluated using the model by determining their position on a trajectory of water stress related decline and response. In both cases observer estimates of crown extent and density were significantly correlated. With the exception of red gum crown density the correlation coefficients were higher for the model supported scale. Using a conceptual model of tree response to water availability improved observer agreement. Supporting subjective assessment systems with a conceptual model is recommended to improve observer agreement in cases where a distinct model of the dominant stressor can be defined. © 2010 Elsevier Ltd. All rights reserved.
Souter N.J.,Land and Biodiversity Conservation |
Wallace T.,Land and Biodiversity Conservation |
Walter M.,Land and Biodiversity Conservation |
Watts R.,Land and Biodiversity Conservation
Ecohydrology | Year: 2014
River red gum (Eucalyptus camaldulensis Denhn.) trees along the lower River Murray, Australia, have suffered severe dieback as a result of river regulation and drought. As an environmental flow initiative, the height of the lower River Murray in South Australia was raised during a period of increased flow in the spring and summer of 2005-2006. This was performed by increasing the level of the rivers in channel weirs. This increased the level of anabranch creeks on the Chowilla floodplain and through horizontal recharge freshened the adjacent groundwater, providing water to riparian river red gums. Groundwater depth rose concurrently with the rise in creek level, likely recharging the saline floodplain water table with fresh creek water. Multistate Markov modelling showed that along four creeks, most healthy trees responded positively to the rise in water level and remained healthy 1year after the surcharge. Healthy trees were three times more likely to respond than stressed trees and thirty times more likely to respond than defoliated trees. Stressed trees were ten times more likely to respond than defoliated trees. Forty eight percent of trees that had no leaves at the start of the study responded to the surcharge by producing new growth. This study demonstrates how existing regulatory infrastructure can be used to manipulate water levels and that the hydrological connection between surface water and groundwater can be used to provide water to riparian trees. © 2013 John Wiley & Sons, Ltd.
Bryan B.A.,CSIRO |
Overton I.,CSIRO |
Higgins A.,CSIRO |
Holland K.,CSIRO |
And 9 more authors.
Modelling for Environment's Sake: Proceedings of the 5th Biennial Conference of the International Environmental Modelling and Software Society, iEMSs 2010 | Year: 2010
Investment in water infrastructure and management can enhance the ecological health of water-dependent ecosystems along highly regulated rivers. Investment in new flow-control infrastructure and management of both existing and new infrastructure can help return natural environmental flows to achieve healthy and representative areas of river ecosystems. In this paper, we developed an integrated model to cost-effectively restore environmental flows and ecosystem health in the River Murray in South Australia. The model integrates a range of hydrological, ecological, economic, and social components. A hydrological model is used to identify spatial and temporal inundation dynamics given flow rates and weir operation. Ecological response models were developed to link three aspects of environmental flows (flood duration, timing, and interflood period) to the health responses of ecosystem components. The infrastructure investments (flow-control regulators and irrigation pump relocation) were sited by interpreting high resolution LiDAR elevation data, digital orthophotography, and wetland mapping information; and their costs were quantified using a spreadsheet-based model. Social values were also estimated using a choice model quantifying willingness to pay for various ecosystem components and these were also included in the model. These diverse datasets and models were integrated in a decision support tool based on non-linear integer programming to investigate the cost-effectiveness of alternative flow levels and timing, existing flow-control infrastructure operation, and new infrastructure investment alternatives, given wider system constraints. The decision support tool can identify a suite of cost-effective infrastructure investments and a plan for their operation specifying where and when to capture and release water in riparian ecosystems. Outputs include a ranking of investment alternative and rules for managing flow-control infrastructure to achieve ecological and social values at minimum economic cost. In this paper we discuss the development and integration of the range of hydrological, ecological, economic, and social components of the model and the objectives of integrated river ecosystem management.