博斯腾湖的咸化与淡化

博斯腾湖的功能是多方面的，在南疆经济建设中很重要。本文对该湖概况、湖体效应、水质演变、水盐平衡、生态环境等作了介绍和分析，提出了治理建议，对湖水淡化作了预测。

SALINIZATION AND DESALINIZATION OF BOSTAN LAKE

Bostan Lake had been the largest fresh water lake of mainland China for a long periodof time. Because of its rich resources and favorable environment,Bostan lake had favorably adjusted the.climate and the river system of Yanqi basin. Around 1967,affected by human activities,the lake experienced slight salinization,lowering of water level, reduction of resources, and worsening of ecological environment. According to the water salt balance analysis,these changes are attributed to: 1 )The intensive agricultural usage decreased fresh water supply to the lake. 2)Highly mineralized farmland waste water was drained into the lake during the 60s. 3)Kaidu River,the main fresh water supply source,had reduced water level for many years. 4)Improper management added negative effect. Since the 80s,.due to appropriate measures undertaken and better natural hydraulic system, the water quality and ecological environment have been improved;and the water level has also raised. However,desalinization is not achievable in short period. This paper derives the mineralization formula for Bostan and predicts the flux of Kaidu River for the next twelve years. If the underground water of Yanqi Basin is extracted and the water in the lake is pumped out increasingly,the calculations indicate that desalinization may be achieved in 2006. Otherwise,at least 20 years are needed for the desalinization.