Wetland management: preparing for climate and coastal change using adaptation pathways

Abstract

Freshwater ecosystems are among the most threatened in the world. The list of threatened species in freshwater ecosystems is greater than that in terrestrial or marine systems and freshwater vertebrates are particularly at risk. Freshwater wetlands have evolved in coastal zones protected from tidal influence by barrier dune systems. Similarly, estuaries have supported zones of low salinity diluted by flows from land, but water resource development has limited these flows and driven ecological change in estuarine systems. These historical uses of river flows, and the impacts of catchment development on water quality and yields, have combined to threaten coastal wetland ecosystems. They are now under increasing threat through climate change driven alterations to hydroclimatic conditions, as well an rising sea levels which risk inundation of low lying coastal regions, including wetlands. Coastal freshwater systems offer considerable ecosystem services to human systems and host significant biodiversity assets. These have been subjected to increased risk through catchment and coastal development, but are now acutely threatened through changed river flows and elevated sea levels that result from climate change. Managing these systems requires an adaptation pathways approach that accommodates human needs, and society’s obligations to global biodiversity.