Loss and degradation of wetlands in southwestern Australia: Underlying causes, consequences and solutions

Abstract

Many wetlands (estimated to be about 70%) have been lost in the coastal plain region of southwestern Australia since British settlement (in 1829), primarily as a result of infilling or drainage to create land for agricultural use or urban development. While further loss is almost universally acknowledged as undesirable, wetland degradation continues with little overt public recognition of the causes or consequences. Obvious and direct causes include nutrient enrichment, salinization, pollution with pesticides and heavy metals, the invasion of exotic flora and flora, loss of fringing vegetation and altered hydrological regimes occurring as a result of urbanization and agricultural practices. Underlying causes include a lack of understanding of wetland hydrology and ecology on behalf of both planning agencies and the private sector, and poor coordination of the many different agencies responsible for wetland management. Public and political awareness of wetland values continues to increase, but sectoral organization and responsibilities for wetland management lag behind. Sufficient scientific information now exists for improved management, protection and restoration of wetlands in southwestern Australia. However, this improvement cannot occur without the necessary political will and corresponding sectoral responses needed to implement coordinated wetland management policies and actions.