长江三峡花岗岩地区坡面产沙及沟道输沙规律

运用砂粒粒组分析方法，对长江三峡花岗岩地区下岸溪流域的坡面产沙及沟道输沙规律进行了研究。结果表明，〈２．００ｍｍ砂粒的累积含量松栎混交林和马尾松林地最多，荒草坡地居中，农坡地和梯田最少，农坡地和质量不高的梯田是花岗岩坡面侵蚀产沙的主要来源：坡面各级砂粒在沟道各断面都有分布，主沟道泥沙输移比接近于１。

Sediment Production on Different Sloping Lands and Sediment Transportation in Gul l y in Granite Region of Three-Gorge of the Yangtze River

Based on the method of sand particle groups analysis,we deal with the sediment production on different sloping lands and the sediment transportation in gully in the granite region in Xia Anxi watershed of Three-Gorge of the Yangtze river.The results show that the maximum in accumulating content of sand particles (diameter<2.00 mm) is the mixed forest land and the pines massohiami forest land,the middle is the uncultivated land and the minimum is the terrace and the cultivated sloping land.The terrace and the cultivated sloping land is the main source of soil erosion and sediment production in the granite sloping land.Every section in the gully has the sand particle distribution of all diameter classes on sloping land.The sediment delivery rate of main gully approaches 100%.