南方典型花岗岩小流域输沙特性时空对比研究——以衡阳武水流域为例

针对中国南方花岗岩小流域输沙特性问题,以湖南省衡阳县武水流域为研究对象,采用MK突变分析方法、双累计曲线法以及流域对比分析方法,综合分析南方典型花岗岩流域输沙时空规律。结果表明:受花岗岩风化土壤的结构、矿物成分等影响,花岗岩流域相比其他流域具有更高的输沙模数,武水流域的输沙模数值可达同气象条件下的非花岗岩流域的数倍以上。与全国很多流域类似,武水流域输沙模数也呈现出阶段性递减变化特征,这与"大跃进"、"农业学大寨"、"家庭联产承包责任制"、"退耕还林"等政策密切相关。但是与其他很多流域不同的是武水流域输沙模数变化的三阶段,主要是受人类活动所致的流域森林覆被变化的影响,水利工程建设对其影响不大。

Spatial-temporal Comparison of Sediment Transport Characteristics in A Typical Granite Watershed in South China： A Case Study of Wushui Watershed in Hengyang County

In this paper, aiming at the problem of sediment transport characteristics of granite small watershed in South China, taking Wushui watershed in Hengyang County, Hunan Province as the research object, the Mann-Kendall catastrophe analysis method, double cumulative curve method and watershed comparative analysis method are used to comprehensively analyze the temporal and spatial law of sediment transport in typical granite watershed in South China. The results show that the granite basin has a higher sediment transport modulus than other basins due to the influence of the structure and mineral composition of the weathered granite soil. Taking the Wushui basin as an example, its value can be several times higher than that of the non-granite basin under the same meteorological conditions. Similar to many basins in China, the sediment transport modulus of Wushui basin also shows the characteristics of gradual decline, which is closely related to the "The Great Leap Forward", "Learn from Dazhai in Agriculture", "The Household Contract Responsibility System", "Return the Grain Plots to Forestry" and other policies, but different from many other basins, the three stages of sediment transport modulus change in Wushui basin are mainly caused by human activities The influence of the change of the cover is not significant.