大型水利水电工程扰动区植被的生态恢复

大型水利水电工程具有防洪、发电、航运等综合效益,是开发治理江河的骨干工程.水利水电工程建设常对项目区自然生态环境带来影响,施工中所产生的岩质边坡、土质边坡、弃土和弃渣等扰动可能导致项目区的生态系统退化、生物多样性丧失、水土流失和地质灾害加剧.扰动区植被生态恢复关系到工程安全运行和其所在区域的可持续发展.以向家坝水电工程为例,研究了大型水利水电工程扰动区植被生态恢复的目标、原则及方法.按生产、生态和社会功能,向家坝水电工程扰动区可划分为工程核心区、服务区和过渡区等3个功能区来系统规划其生态恢复.结合各自的功能需求和干扰特征,各功能区可采取相应的生态恢复技术和配置适宜物种来构建植物群落,形成结构稳定、多样性丰富、具有复合功能的植被景观.还简要评价了向家坝水电工程植被恢复现状,提出一些完善其生态恢复的建议.

VEGETATION RESTORATION IN DISTURBANCE AREA OF LARGE HYDROPOWER PROJECT——A CASE STUDY OF XIANGJIABA HYDROPOWER PROJECT

Large water resources and hydropower project possessed comprehensive utilization benefits for flood control,power generation and navigation improvement. It will be the vital important and backbone project in harnessing and developing of the river. However, the construction of large hydropower projects often brings about negative effects to surrounding environment. Four common disturbance types in the construction including rock side slope,soil side slope,abandoned soil and abandoned residue will result in ecosystem degradation,biodiversity loss, water and soil loss,and geologic damage. Ecological restoration of the degraded ecosystem and vegetation resulted from the disturbance contributes to the sustainable utilization and development of the project and local society. This paper, taking Xiangjiaba hydropower project as a case,studied the objective,principles and methods for ecological vegetation restoration of disturbed area of large hydropower project basing on the theory of restoration ecology. According to the function of hydro-power production,society and ecology,the disturbed ecosystem of Xiangjiaba hydropower project was divided into three functional zones for restoration which included engineering core,engineering service and engineering transition zone. The engineering core zone undertook the function of hydropower production, tourism and ecology;the engineering service zone not only provided support for the core zone with living, office,traffic and other affiliated facilities, but also with culture and ecological service;the engineering transition zone played a role of ecological buffer belt between the hydropower project and surrounding environment which could reduced disturbance from the project to surrounding environment. Each zone has its specific restoration objects and disturbance characteristic,and should be restored using different ecological restoration technologies and appropriate plant species to rebuild plant communities and good landscape pattern with stable structure and rich biodiversity. Some suggestions were put forward to improve the ecological restoration of Xiangjiaba hydropower project after evaluated briefly its restoration situation.