Lakes Sorell and Crescent Rehabilitation Project: Ecosystem Dynamics and Ecological Modelling

<p>A decline in the trout fishery, water quality and ecological values of lakes Sorell and Crescent has occurred over the past few years. In light of these problems, the Inland Fisheries Service (IFS) secured State and Commonwealth (Natural Heritage Trust) funding to implement on-ground works and formulate management options to address the recent environmental decline. The key problem associated with the lakes is low water levels due primarily to drought conditions and competition for water by various users. A multi-disciplinary project was adopted to address the situation – the <i>Lakes Sorell and Crescent Rehabilitation Project</i>. This project was comprised of ten sub-projects targeting key areas of physical and biological importance to the functioning and management of lakes Crescent and Sorell. The ten sub-projects were:</p> <p></p><ul> <li>Lake Crescent Outflow Screen Duplication</li> <li>Mountain Creek Rehabilitation</li> <li>Catchment Management Plan</li> <li>Water Management Plan</li> <li>Water Quality</li> <li>Wetlands</li> <li>Aquatic Fauna</li> <li>Recreational Fisheries</li> <li>Carp Management</li> <li>Ecosystem Dynamics and Ecological Modelling</li> </ul><p></p> <p>This report outlines some of the findings and management recommendations for the <i>Ecosystem Dynamics and Ecological Modelling</i> sub-project.</p> <p>The objectives of the <i>Ecosystem Dynamics and Ecological Modelling</i> sub-project of the <i>Lakes Sorell and Crescent Rehabilitation Project</i> were to:</p> <p></p><ul> <li>Investigate the significance of biotic and abiotic interactions present in lakes Sorell and Crescent.</li> <li>Determine the mechanisms responsible for contrasts in trophic dynamics.</li> <li>Assess the significance of trophic dynamics in influencing water quality.</li> <li>Apply a robust computer-based modelling framework to lakes Sorell and Crescent that incorporates all significant meteorological, hydrological, physical and biological processes.</li> <li>Calibrate the model with information gathered from the lakes in the past.</li> <li>Verify the model by comparing predicted information with actual field measurements.</li> <li>Utilise the model to assess outcomes of possible management strategies.</li> </ul><p></p>