荆江与洞庭湖区近50年水沙变化的研究

Research on the Variations of the Water and Sediment for Recent 50 Years in the Jingjiang River and Dongting Lake Area

在前人研究成果的基础上,对荆江与洞庭湖区的分流分沙变化、泥沙淤积变化、水位变化三个方面进行了总结。自20世纪50年代以来,荆江三口分流分沙减小,荆江分流加大;洞庭湖的泥沙淤积减缓,湖盆内的淤积部位主要是受湖盆形状和水流来向的影响;荆江河段冲刷,城陵矶-汉口河段淤积;荆江与洞庭湖汛期水位相对抬高。泥沙淤积是水沙变化的主要因素,江湖流量的分配在水沙变化中起着重要作用,人类活动也扮演着重要的角色。

<Abstrcat>Based on the results of precedent researches,the variations of the split-flow,the sediment deposition and the water level are synthesized.Since the 50 s in the 20 th century, the water and sediment which run into the Three Mouths in the Jingjiang River have reduced greatly.Severe deposition has occurred in the Chenglingji-Hankou Reach and most part of the Dongting Lake.Nevertheless,the water level has been raised more or less.Of all the factors that influence the variations of water and sediment,sediment deposition is the most important.Meantime,the discharge distribution of water and sediment and human activities have palyed important roles in the evolutions.