变化环境下黄河流域河流健康诊断研究
Health Diagnosis of River System in the Yellow River Basin Under Changing Environment
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摘要: 黄河是中华民族的母亲河,水沙关系不协调、洪水灾害频繁,一直是黄河流域治理的主要难题.近年来黄河来水来沙减少,水沙关系发生深刻变化,极端气候事件频发,黄河河道边界条件发生了较大的变化,沿黄地区经济社会快速发展,变化环境下开展黄河流域河流健康诊断尤为必要.本研究采用信息熵和熵权法等方法研究黄河流域河流健康发展演变特征并提出《河流健康指数》.结果表明:(1)分析河流系统健康程度,1980~1986年黄河流域河流系统总体趋于健康状态,1987~1999年河流系统总体表现为不健康,2000~2019年整个河流系统又向着有序、健康方向发展;(2)分析河流健康指数趋势发现,1980~1984年河流系统向好发展,1984~1999年河流系统呈现出越来越不健康的趋势,2000~2019年河流系统呈现出向好发展态势;(3)1986年以前河流系统敏感因素为宁蒙河段主河槽过洪能力,1987~1999年期间敏感因素为宁蒙河段主河槽过洪能力和花园口总水量,21世纪以来敏感因素为黄河下游总冲淤量和来沙量;黄河下游总冲淤量和宁蒙河段主河槽过洪能力为整个时期的敏感因素.研究结果可为黄河流域生态保护和高质量发展提供支撑.Abstract: The Yellow River is the “mother river” of the Chinese nation.The unbalanced relationship between water and sediment and frequent flood disasters have always been the main challenges in the governance of the Yellow River Basin or YRB.In recent years, the Yellow River channel have undergone major changes caused by the fluctuated water-sediment relationship, meanwhile, along with frequent extreme weather events, the social economy in the basin has developed rapidly.Under this changing environment, a river health diagnosis for the YRB becomes essential.In this study, methods such as information entropy and entropy weight method are adopted to study the characteristics of the healthy development and evolution of the Yellow River Basin through a new index “River Health Index”,shortly RHI.The study results indicate:(1) A health analysis of the river system shows that the YRB was in a healthier state from 1980 to 1986 and was generally unhealthy from 1987 to 1999;and from 2000 to 2019,the river system developed towards a healthy and well-aligned direction.(2) An analysis of the trend of the RHI finds that the river system developed better from 1980 to 1984,showed an increasingly unhealthy trend from 1984 to 1999,and a positive trend from 2000 to 2019;(3) The sensitive factor of the river system was the flood capacity of the main channel of the Ningxia-Inner Mongolia river section before 1986;from 1987 to 1999,the sensitive factors were the flood capacity of the main channel of the Ningxia-Inner Mongolia river section and the total water volume of Huayuankou; since the 21st century, the sensitive factors are the total scouring and silting as well as the incoming sediment of the lower reaches of the Yellow River.For the entire period, the sensitive factors are the total scouring and silting of the lower Yellow River and the flood capacity of the main channel of the Ningxia-Inner Mongolia river section.These results can provide support for the ecological conservation and high-quality development of the YRB.