Conservation and management of tropical Asian and Australian inland waters: Problems, solutions and prospects

Abstract

This paper summarizes the individual contributions contained in the volume Inland Waters of Tropical Asia and Australia: Conservation and Management. It explores the principles and philosophies, as well as the problems and constraints, related to the conservation and management of tropical inland waters in general and Australian and Asian systems in particular. It also addresses a range of issues specific to the conservation of individual habitat types: i.e. rivers and streams, lakes, and wetlands. With regard to the conservation of running waters in the tropics, it is evident that future research should focus on the impact of river regulation and flow control on the aquatic biota. Patterns of energy flow and nutrient cycles, and interactions between lotic systems and their drainage basins or catchments, are in need of investigation also. Eutrophication of standing water bodies is a major concern, especially in China where many of the region's large natural lakes are concentrated. Possible management strategies to reduce nutrient loads include source reduction and ‘nutrient-stripping’ through fish farming. Here closer examination of the potential negative impacts of prevailing management practices on the overall biodiversity of lentic systems is called for, as protection of the habitats does not automatically translate into preservation of their natural inhabitants. This point is reinforced by the effects of exotic introductions on the native aquatic fauna of tropical Asia and Australia, and a serious lack of information (and predictive ability) regarding this important subject is evident. The complexity of wetland systems poses a real challenge to environmental scientists and managers, and it is clear that successful conservation and management of these endangered habitats can only be accomplished by a multi-scale-multidisciplinary-multi-sectoral approach. It is argued that environmental monitoring and, in particular, biological monitoring should form an integral part of all conservation programmes. The complementary nature of monitoring techniques suitable for investigations at different scales, as well as the importance of proper experimental design and statistical analysis, are discussed. Suggestions are made with the aim of improving the scientific rigour of environmental monitoring, establishing sound and relevant water-quality standards, and providing better training and career prospects for conservation personnel, particularly those in developing countries. The paper concludes with comments on the conflict between the economic development of some tropical countries and the safeguarding of biodiversity, and the role that scientists can play in influencing the outcome of this conflict. Some recommendations are made which could serve to direct the efforts of limnologists towards conservation and management of tropical inland waters.