长江中游水文情势变化及对鱼类的影响分析

为分析三峡水库蓄水后长江中游河道水文情势变化情况及其对鱼类产卵繁殖的影响，采用水文变化指标体系和变动范围法，对宜昌站水文情势变化进行了定量分析，得出了变化程度较为剧烈的水文参数。通过对照典型鱼类的历史产卵量与历史流量过程，归纳了典型鱼类四大家鱼的生态水文需求，得出了影响鱼类产卵繁殖的主要水文参数。提出了水文情势变化影响鱼类产卵繁殖过程的概念性模型。在分析的基础上，揭示了长江中游水文情势变化对鱼类产卵繁殖的影响。

Analysis on hydrologic alteration of middle Yangtze River and its impact on fish

In view of the hydrologic alteration of middle Yangtze River after the impoundment of Three Gorges Reservoir and its impact on the spawning of fish,the hydrologic alteration of Yichang hydrological station is analyzed quantitatively using indictors of hydrologic alteration(IHA) and range of variability approach(RVA) and we point out the hydrologic parameters which have changed to a large extent.The eco-hydrological demand from the four major Chinese carps are concluded by comparing the historic oviposition amount and runoff time series.The major hydrologic parameters that affect the spawning of fish are found.A concept model for the impact of hydrologic alteration on the spawning of fish is established.On the basis of analysis,the impact of hydrologic alteration on the fish spawning is revealed.