三峡蓄水运行后中华鲟产卵场水动力特性分析

Hydrodynamic characteristics analysis of Chinese sturgeon spawning ground after operation of Three Gorges Project

三峡工程蓄水运行造成葛洲坝下游同期下泄流量减少，致使葛洲坝下中华鲟产卵场水文及水动力特性发生改变。根据对中华鲟产卵繁殖情况的监测资料，虽三峡蓄水运行后在葛洲坝下中华鲟产卵场每年仍能监测到中华鲟产卵行为的发生，但其产卵数量和质量都较三峡蓄水前减小。为进一步探明中华鲟自然繁殖对水动力的需求范围及耐受区间，本文在建立中华鲟产卵场水动力数学模型的基础上，对06～10年各年中华鲟产卵时段产卵场的水动力特性进行数值反演，并采用统计分析的方法获得三峡蓄水至156m后中华鲟产卵区域的水动力特性及中华鲟产卵繁殖的水动力耐受区间。

Impoundment of the Three Gorges project causes a large reduction in the river flow downstream to Gezhouba dam and further causes significant changes in the hydrological and hydrodynamic conditions of the Chinese sturgeon spawning ground. The monitoring data of spawning and reproduction reveal that the spawning has been lowered in quantity and quality, although after the impoundment the spawning behavior in the downstream site next to Gezhouba has been detected. To further prove the demand range and the tolerance interval of hydrodynamics for the sturgeon reproduction, this study developed a mathematical model of spawning ground hydrodynamics, and obtained inverse solution from the 2006-2010 hydrodynamic data series of river flow at the spawning sites. And statistical analysis methods were adopted to analyze the simulation data for the demand range and the tolerance interval in the case of Three Gorges water level higher than 156m.