金沙江流域生态地质环境现状及其对梯级水电站工程开发过程中生态环境保护的建议

APPRAISAL AND FORECAST OF THE INFLUENCE OF PROJECTS DEVELOPMENT OF STAVED POWER PLANTS ON THE ECO-ENVIRONMENT IN THE JINSHAJIANG RIVER WATERSHED

金沙江流域地跨横断山断块抬升高山、高原褶皱隆起中一低山和四川盆地掀斜台陷深切丘陵三种环境地质域,地质环境复杂,地形起伏大,流域水平及立体气候变化明显,由此营造出复杂的生态地质环境系统。流域水资源储量丰富,是中国最大的水电能源基地,流域规划开发12座梯级电站。梯级电站的开发必然与流域的生态地质环境发生相互作用,作用的正负效应事关水电开发本身的安全,也维系流域乃至西部生态环境的安全,因此必须客观地评价流域生态地质环境现状,预测梯级电站修建后可能产生的影响。文章结合流域的生态地质环境现状,筛选出27个评价指标,将其分成斜坡(岸坡)稳定性评价子系统、水土流失与水库淤积评价子系统、生态环境演化评价子系统和人类活动评价子系统四大子系统,在此基础上建立金沙江流域“水电工程开发对生态地质环境影响评价系统”。最后, 利用该评价系统将流域划分为26个生态地质环境质量片区,分述其现状和梯级电站开发影响。

The Jinshajiang River watershed crosses three landform regions including the Hengduan Mountain of rupture and uplifted high mountains, the low mountains and the middle mountains for plateau show great relief and climate fluctuations, and hills in the Sichuan Basin are of tilt falling and incision. In the watershed, the geological environment is complex, the terrain changes actually, the horizontal and three-dimensional climate changes greatly. All of these factors cause the complex EGI-LS （ecology-geology environment system. ）. Over the Jinshajiang River, which contains abundant water, resources there will develop 12 staved power plants, and constituting the biggest water and electricity energy base in China. The staved power plant development inevitably influences the EGES, the positive and negative effects not only influence the security of water and electricity development itself, but also also maintains the watershed, even that of the West EGES. Therefore, it is valuable to appraise objectively the present situation of the EGES, and forecast the possible influence of staved power plant construction. In this paper, 27 appraisal targets are filtrated and classified as four subsystems： bank slope stability, soil erosion and reservoir silting-up appraisal subsystem, ecological environment evolution appraisal subsystem and human activity appraisal subsystem, so as to establish “the ecology- geology environmental effect appraisal system of water and electricity projects” over the Jinshajiang River. Finally, the system is used to divide this watershed into 26 ecology-geology environment quality sub-regions, describe its present situation, and forecast the potential influence of water and electricity development.