甘肃省黄土高原典型小流域侵蚀沟道特征

目的]对甘肃省黄土高原典型小流域侵蚀沟道的分级分类进行简要研究,为进一步推动该区水土保持和生态治理工作提供理论基础。方法]在甘肃省第一次全国水利普查结果的基础上,运用GIS技术,采用地貌几何定量数学模型分级方法,定量化分级沟道,并从地质、地貌、大小以及形状对侵蚀沟道进行分类,由此来推断黄土高原区侵蚀沟道的特征。结果]甘肃黄土高原典型小流域侵蚀沟道主要以Ⅰ级沟道为主,其中丘陵沟壑区主要以半开析、中度割裂、半主沟型为主;高塬沟壑区主要以半开析、中度割裂、支沟型为主。结论]丘陵沟壑区第五副区沟壑狭窄陡峭,沟道破碎化程度高,水土流失量高,治理难度大,沟道难以利用。

Characteristics of Erosion Gullies in Small Watershed Scale on Loess Plateau in Gansu Province

Objective] The paper studied the classification of the erode gullies in small typical watersheds on the loess plateau in Gansu Province aimed to lay foundation for the better development of soil and water conservation and ecological management in the Loess Plateau.Methods] Based on the results of the first national water resources and water power investigation, using GIS technology and math model of physiognomy geometry ration, the gullies were graded quantitatively and erosion gullies are classified from geology, geomorphology, size, and shape. Therethrough, the characteristics of erosion gullies in the Loess Plateau were inferred from.Results] The results showed that in small watershed scale on Loess Plateau in Gansu Province, most of the erosion gullies are those, in hilly and gully regions, that have semi-opened, moderate fragmented and semi-main groove typed characteristics; In Loess gully regions, that have semi-opened, moderate fragmented and branch gully typed characteristics.Conclusion] In the hilly and gully region, the fifth gully is narrow and steep, the gully fragmentation is high and the amount of soil erosion is great. It is difficult to manage and use the gullies.