【作者】 褚忠信；

【导师】 翟世奎；

【作者基本信息】 中国海洋大学 ， 海洋地质， 2006， 博士

【摘要】 2003年,三峡工程二期工程完成,并且在6月份一期蓄水,将三峡水库坝前水位提升到135m(吴淞高程)。三峡工程引起的环境生态问题是国内外十分关心的问题,而泥沙研究又是三峡工程的核心问题之一。泥沙问题不仅关系到三峡水库的正常运行、水力发电和长江航运,还与长江三角洲的冲淤演化以及东海的沉积模式紧密相关。另一方面,长江入海泥沙又与河口近海以及大陆架颗粒态地球化学物质组成密切相关,从而影响到河口海岸和大陆架生态系统和环境。因此,研究三峡水库蓄水对长江泥沙的影响有着重要的实际价值和理论意义。本文依托国家973项目“中国典型河口—近海陆海相互作用及其环境效应”,首先统计分析了中国9条主要河流(长江、黄河、珠江、淮河、松花江、钱塘江、海河、辽河、闽江)入海水沙通量近半个世纪以来的变化情况,并分析了引起河流入海泥沙通量减少的一些原因。在此基础上,抓住三峡水库一期蓄水的有利时机,对蓄水期间和初期的从长江上游到河口以及邻近海域的泥沙进行了比较及时、比较完整的分析。本文的主要研究成果如下:1.中国9条主要河流入海水沙通量变化(1953-2003)按照近半个世纪以来河流入海年径流量和年输沙量的变化趋势,中国主要入海河流有两种类型。入海输沙量呈减少趋势的河流包括:自二十世纪60年代以来输沙量开始减少的黄河、长江、辽河和淮河,以及分别自二十世纪80年代和90年代以来输沙量开始减少的海河和闽江;入海输沙量变化不大的河流包括:珠江、钱塘江和松花江。另一方面,入海径流量呈减少趋势的河流包括:自二十世纪60年代以来入海径流量开始减少的黄河、淮河和辽河,以及二十世纪80年代以来入海径流量开始减少的海河;入海径流量变化不大的河流包括:长江、珠江、松花江、钱塘江和闽江。按照近半个世纪以来河流入海年径流量和年输沙量的相关性,中国主要入海河流可以分成三种类型:高水沙相关型河流(R2=0.79～0.88):海河、黄河、辽更多还原

【Abstract】 The Three Gorges Project (TGP) on the Yangtze River, the largest hydropower-complex project ever built in the world, completed its Phase-II construction and Phase-I water storage in 2003, finally elevating the pool level to about 135 m above mean sea level at the dam. The potential eco-environmental problems induced by the TGP are widely concerned at home and abroad. Sediment research in particular is one of the most important concerns about the TGP. The Three Gorges Reservoir (TGR) sedimentation will affect the normal operation of the TGR, hydropower generation, and navigation. The Yangtze River sediment entering the sea is closely related to the evolution of the Yangtze River mouth, mouth bar, river delta, and even deposition patterns of the East China Sea. On the other hand, the Yangtze River sediment features are closely related to the particulate geochemical compositions, which have important effects on the estuarine, coastal, and even shelf areas ecosystem and environment. Thus, it is necessary and urgent to examine the effects of the TGR water storage on the Yangtze River sediment, which has important practical and theoretical significance.Supported by the National Basic Research Program of China for Land-Sea interaction and its effect on the environment in the typical estuaries and offshore areas of China (Project No: 2002CB412400), the thesis firstly examined the temporal variability in water and sediment entering oceans by 9 major rivers in China during 1953-2003, including the Yangtze River, Yellow River, Pearl River, Huaihe River, Songhuajiang River, Liaohe River, Qiantangjiang River, Minjiang River, and Haihe River, and further, identified some factors leading to such temporal variability. Secondly, the thesis took the excellent opportunity of the Phase-I water storage of the TGR timely and systematically examined its effects on the sediment of the Yangtze River mainstream, estuary and adjacent seas.The main results in the thesis were drawn as follows:1. Temporal variability in flux of water and sediment entering seas by 9 major rivers in China更多还原