The conservation of two large lakes: Tahoe and Baikal

Summary

Water supplies are a limiting resource for human habitation and shortages have reduced the quality of life throughout the world. Limnologists have a responsibility to society to provide advice for conservation and management of the resource. Eutrophication remains a major threat to the recreational and aesthetic value of streams, lakes, and reservoirs. Results from three decades of study of Lake Tahoe, still in the earliest stages of eutrophication, can be generalized for lakes as far distant as Lake Baikal in Russia. Although major attention has been directed towards controlling phosphorus loading derived from sewage, nonpoint nutrient loading from runoff and dry and wet atmospheric deposition are important sources of both nitrogen and phosphorus. Forest fires contribute to nutrient loading of surface waters and algal growth is often co-limited by both nitrogen and phosphorus. Water and airshed management practices should focus on reducing nutrient loading. Wetland ecotones should be maintained or reestablished for denitrification and sediment removal. Forestry practices and construction of roads and buildings must be regulated by a regional planning agency to minimize erosion.