29 Aug Anne Jensen
Anne Jensen, Australia.
Dr Anne Jensen is an environmental consultant with a long and passionate interest in the River Murray and wetland environments in Australia. Her career has spanned developing government policies and management strategies, managing on-ground wetland repair projects, undertaking research of floodplain ecosystems, and providing technical advisory services as a consultant. Her projects have covered most wetlands in South Australia and across the Murray-Darling Basin, as well as case studies in Denmark and Canada. She is particularly interested in the topic of environmental flows, and the practical aspects of delivering water for positive environmental benefits. Anne also sees knowledge-sharing as vital in making best use of our accumulated experiences in managing water resources and wetlands.
Presentation Title:Where have all the flowers gone?
Since 1998, on-ground projects have sought to simulate natural water regimes in Australian wetlands. Trials returning water to the environment started in 2004, aiming to avoid irreversible damage in icon habitats during severe drought. The Water Act 2007 reserved water for environmental use and started a process to reverse over-allocation. Significant scientific effort since has sought to define environmental flow requirements for specific species or habitats, but the challenge remains to return water on-site and to demonstrate that environmental outcomes are being achieved. Environmental watering projects for red gum, black box and lignum communities on the Lower Murray floodplain are being based on natural phenological cycles, particularly seed fall. If timing of flowering is known, watering can be timed to increase survival of bud and fruit crops, thus increasing flowering volume and seed production, and to provide moist soil to coincide with maximum seed fall to trigger germination. However, extreme variability and inconsistency in annual climatic conditions is hindering confirmation of seasonal patterns, and more annual cycles need to be monitored for certainty on timing for specific locations and communities. As well as attempting to determine ‘what does the environment need?’, researchers and managers face the dilemma that a changing hydrograph may not sustain natural ecosystems over the same range with all species and habitats still present. Water requirements derived from ecosystems which evolved over centuries will be applied in significantly modified rivers in a changing climate with poor predictability of future conditions in the next 5-10 years. When lack of data mean computer programs can’t deliver definitive answers on timing, some innovative thinking is required. Strategic adaptive management may unlock the key findings, where scientists and managers undertake coordinated field trials with monitoring and feed-back loops to test hypotheses and confirm environmental water requirements through the adaptive management process.