Valleys of salt, channels of water, pools of life: environmental aspects of salinity engineering

摘要

Aquatic systems (rivers, creeks and lakes) and valley floors in the Wheatbelt region of Western Australia have often been the first to display symptoms of salt damage because they are the lowest points in the landscape. As a consequence, the receiving bodies for many drainage networks will be environments which are already experiencing secondary salinisation. They no longer contain a diverse range of freshwater species but instead, a smaller suite of salt tolerant forms. Unfortunately, there is a perception that all saline waterbodies possess few existing ecological values. Our most recent research findings suggest that, although these systems have changed, some still possess important ecological functions and values. It is a matter of urgency that we identify the wetlands with the highest ecological values within the Wheatbelt and ensure that these are not affected by drainage. At a landscape scale, we also need to consider the downstream impacts of large-scale drainage networks. Will they ultimately affect water quality in downstream estuarine and near-shore marine regions? On a more positive note, we also need to identify where the additional water delivered by deep drains may create new ecosystems and enhance ecological values.