【作者】 高鹏；

【导师】 李锐； 穆兴民；

【作者基本信息】 中国科学院研究生院（教育部水土保持与生态环境研究中心） ， 土壤学， 2010， 博士

【摘要】 黄河中游(河口镇-花园口区间)的水沙变化及其驱动因素是社会各界关注的焦点之一,同时也是评价黄土高原生态建设和生态系统修复的一个重要依据。本文以黄河中游为对象,利用研究区1950-2008年降水、径流、输沙序列资料,采用数理统计及小波分析等方法,分析了黄河中游各区间水沙变化过程及其对降水及人类活动的响应,并利用灰色预测模型对水沙变化趋势进行了模拟预测研究。得到以下主要结论:(1)分析了近60年来黄河中游水沙特征变化。1950-2008年,黄河中游年均来水量及来沙量分别为165.2×10~8m~3、8.2×10~8t,多年平均变差系数分别为0.5、0.7。黄河中游来水来沙量变化具有明显的阶段性。其中来水量分为三个时期:1950-1970年为丰水期;1971-1985年为平水期; 1986-2008年为枯水期。来沙量分为两个时期:1950-1981年为丰沙期;1982-2008年为枯沙期。黄河中游年均来水来沙量存在明显的周期性变化规律。年均来水量存在27a、10a、以及4a周期,其中第一主周期为27a;年均来沙量存在31a、20a、以及7a周期,其中第一主周期为31a。(2)黄河中游来水来沙量呈显著的减小趋势,且都通过了Pettitt’s统计检验指标临界值(P=0.05)。来水量与来沙量分别从1985年、1981年发生突变性减少趋势。突变年份后,区间年均来水来沙量在同一频率下均呈显著减少趋势。年均来水量在突变年份后减少幅度为43.9%-69.8%。其中在丰年减少51.6%;平年减少44.0%;枯年减少60.5%。年均来沙量在突变年份后减少幅度为44.9%-96.2%。其中在丰年减少46.8%;平年减少61.4%;枯年减少96.0%。(3)降水和人类活动是影响黄河中游水沙变化的主要驱动因素。降水和人类活动的减水贡献率分别为30%、70%;减沙贡献率分别为20%、80%。定量分析了人类活动对黄河中游水沙变化的影响程度。生产生活用水是区间来水量减少的一个主要因素。区间年均耗水量约为45.0×10~8m~3,占人类活动减水总量的73.8%。水土保持是一项减水减沙的综合性措施,是区间来沙量减少的一个主要因素。由于水土保持措施每年的减水减沙量分别为6.0×10~8m~3、2.7×10~8t,分别占人类活动减水减沙总量的9.8%、52.9%。大中型水库的泥沙淤积是区间来沙量减少的一个重要因素。由于水库、河道淤积泥沙年均约1.8×10~8t,占人类活动减沙总量的35.3%。(4)利用GM灰色预测模型对黄河中游河龙区间水沙变化进行了模拟研究。虽然模型预测结果较实测值都要偏大,但该方法对水沙变化趋势的波形模拟能力较强,能较为准确地判断出实测序列的峰谷变化趋势。更多还原

【Abstract】 The middle reaches of the Yellow River (from Toudaoguai to Huayuankou) water and sediment and their driving factors is the focus of attention of the community. It is also an important basis for evaluation of ecological construction and ecosystem restoration in the Loess Plateau. In this paper, the middle Yellow River as the research object, based on the precipitation, streamflow and sediment discharge series data (1950-2008), using mathematical statistical test methods and wavelet method, analysis of streamflow and sediment discharge variation and its impact on precipitation / response to human activities. And to use gray prediction model to simulate changes in streamflow and sediment discharge prediction. The main conclusions are as follows:(i) Analysis the change of streamflow and sediment discharge eigenvalues nearly 60 years in the middle reaches of the Yellow River. The annual average streamflow and sediment discharge is 165.2×10~8m~3 and 8.2×10~8t respectively; and the mean coefficient of variation(Cv) is 0.5 and 0.7 respectively in the middle reaches of the Yellow River during 1950-2008. Changes in streamflow and sediment have obvious stages. In which streamflow is divided into three periods: 1950-1970 for the wet period; 1971-1985 for the normal period and 1986-2008 for the dry period. Sediment discharge is divided into two periods: 1950-1981 for the wet period and 1981-2008 for the dry period. Streamflow and sediment discharge have significant periodicity. Streamflow periodicity is 27a, 10a and 4a, and the first main periodicity is 27a. Meanwhile, the sediment discharge periodicity is 31a, 20a and 7a, and the first main periodicity is 31a.(ii) Results show that strong decreasing trends in annual streamflow and sediment discharge have existed of the middle reaches of the Yellow River. Change point analyses reveal that more rapid declines for streamflow began in 1985, and sediment discharge began in 1981 (P=0.05). The average annual streamflow and sediment discharge shows a significant decreasing trend at the same frequency after the transition year. Decrease of streamflow after the transition year ranged from 43.9% to 69.8%. In which its decrease 51.6% for wet years, 44.0% for normal year and 60.5% for dry year. Decrease of sediment discharge after the transition year ranged from 44.9% to 96.2%. In which its decrease 46.8% for wet years, 61.4% for normal year and 96.0% for dry year.(iii) Precipitation and Human activity are the main driving factors affecting the streamflow and sediment changes in the middle reaches of the Yellow River. Precipitation and human activities contribute rate of streamflow reduction was 30% and 70%, and the contribution rate of sediment reduction was 20% and 80%. Quantitative analysis the impacts of human activities on changes of streamflow and sediment discharge in the middle reaches of the Yellow River. Diversion is a major factor in reduction stereamflow of the middle reaches Yellow River. The average annual water consumption is about 45.0×10~8m~3, accounting 73.8% for the total amount of water reduction impacting of human activities. Soil and water conservation is a comprehensive water and sediment reduction measures,and it is a a major factor in reduction sediment of the middle reaches Yellow River. Annual reduction in water is 6.0×10~8m~3, and sediment is 2.7×10~8t, respectively, accounting 9.8% and 52.9% for the total amount of water and sediment reduction impacting of human activity. Large and medium-size reservoirs were constructed to reduce the sediment discharge is an important factor in the middle reaches of the Yellow River. The annual average is about 1.8×10~8t due to sediment deposition of reservoirs and riverway, accounting 35.3% for the total amount of sediment reduction impacting of human activities.(iv) Gray prediction model was used to simulate changes in streamflow and sediment discharge prediction in middle reaches of the Yellow River. This method is good for waveform simulation, and be able to more accurately determine the peak and valley trend of hydrological data series.更多还原