黄土区小流域坡沟系统侵蚀与淤地坝拦蓄特征演变响应研究

Study on Responding of Feature Evolution about Slope-gully System Erosion and Check Dam Interception of Small Watershed on Loess Plateau

通过实地调查和建立关地沟坡沟系统概化模型的有限元模拟,结合数学推导,研究坡沟系统的剩余坡长随坝地淤高的相关关系。结果表明,随着坝地淤高,坝库淤积的泥沙量与坝高和相同淤积高度下的各淤积阶段淤积泥沙量及淤积高度分别满足二项式的相关关系;相同的产沙量落淤在坝地上垂直淤积高度与坝地当前淤高满足乘幂的相关关系。

Through field investigation and analysis,the generalized model of slope-gully system in Guandigou Watershed was established.Combined with mathematical derivation,the relationship about the remaining slope length of slope-gully system changing with gradual rise of dam land was obtained.The results showed that：（i）the function about the sediment silted in dam reservoir changing with dam land vertical silting higher satisfying binomial correlation;（ii） the function about sediment amount silted of every alluvium following dam land silting the same higher satisfying binomial correlation;（iii）the function about vertical sedimentation height of 100 cubic metre sediment falling on dam land changing with dam land current sedimentation height satisfying exponentiation correlation.The result can provide scientific foundation and technological support for check dam stabilizing slope and gully,lightening gully erosion and dam system planning and construction in small watershed on loess plateau.