三峡工程影响下游水生态环境的径流调节作用分析

Analysis on Flow Adjustment Functions of the Three Gorges Project which Affect the Downstream Aquatic Ecosystem and Environment

三峡工程作为长江上最大的综合水利枢纽工程,其建成运营为区域可持续发展带来巨大社会经济效益的同时,会产生广泛且明显的生态环境影响。径流是河流生态系统中起决定性作用的要素,三峡工程运行对水文情势的调节是产生水生态环境影响的关键驱动力。从工程规模、设计运行方式和实时调度等方面分析了三峡工程对下游径流的调节作用。三峡工程蓄水运行以来,对坝下流量调节有限,除蓄水期和供水期外,基本维持天然流量过程,年下泄总量不变;三峡工程对下游水文过程的影响主要集中在蓄水期和供水期。

As the largest water conservancy complex in the Yangtze River,the Three Gorges Project will produce far-reaching eco-environmental effects as well as enormous social-economic benefit in terms of flood control,hydropower generation and navigation over the Yangtze River Basin.Flow regime plays a key role in the aquatic ecosystem.The adjustment of the Three Gorges Project（TGP）running on hydrological situation is a critical force on aquatic eco-environmental impact.In this paper,The TGP＇s adjustment on downstream flow was analyzed in terms of project size,operation mode and real dispatch.Since the TGP was impounded,the flow adjustment under the dam was limited,and natural hydrological process was maintained basically except impounded period.It also could be found that annual discharged flow was unchanged and the TGP＇s effects on downstream hydrological process occurred mainly during impoundment and water supply.