Lake Alexandrina as an ecosystem providing benefits to mankind

Abstract

The way in which we manage our resources is an issue that is becoming increasingly more important. Complex resources providing benefits to man in a number of different and, to some extent, mutually exclusive ways cannot always be easily managed. Lake Alexandrina is an example of such a complex resource. The aim of this study is to provide the data base and analysis required by the lake managers for appropriate management into the future. A recent report (N.Z. Department of Lands and Survey et al., 1980), has identified thirteen management objectives. The authors' study stems from the concern that these management objectives may not be attainable. Three major benefit flows are presently derived from the lake. These are agricultural benefits from the surrounding catchment, recreational benefits and the benefit derived from the lake's function as a wildlife refuge. These flows are interactive and an increase in demand for any one of them may reduce the ecosystem's capacity to provide the others. Before we.can describe the impact of future demand on the lake we need to comprehend the present benefits and the ecosystem's current stability.