开发羊卓雍湖水电站对生态环境的影响

IMPACT OF YANGZHUOYONG LAKE HYDROPOWER ON ECOLOGICAL ENVIRONMENT IN TIBET

在调查羊卓雍湖资料的基础上,估算了湖内矿化度的变化。该湖浮游植物具有品种多,数量少的特点。预计电站建成后湖中水温与营养元素变化不大,浮游生物的分布和组成以及鱼类的品种及组成亦基本上不会发生变化,因而其水生生态系统变化不大。另外电站也不会对陆生生态系统带来很大的冲击,而局地气温升高和大量湖滩地的出现还可能对农牧业生态系统带来较好的影响。

After a careful study on background, the change of mineralization degree in the lake was determined. The results sumulated show that the water of the lake, with a mineralization degree of 1900 mg/L , will be unlikely changed into fresh water even after more than 100-year power station running. There are 53 genera of phytoplankton and 42 genera of zooplankton in the lake, characterized by species diversity and the lack of biomass as other oligotrophic lakes. It is predicted that the change of water temperature and nutrient is not great, so the impact on the characteristics of plankton and fish can be negligible. After developing the power station, the impact on terrestrial ecosystem is expected to be not great. But the temperature in summer will increase by 0.2~0.4℃,a benefit to some crops. Besides, the new beach abandoned by water is favourable for the development of stock-raising and agricuture. Finally, the remedial measures for ecological environment have been devised in case unfavourable impact occurs.