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通过对嘉陵江上游严重退化区植被恢复对小流域产流产沙的影响研究,结果表明:各小流域沟道侵蚀模数低于坡面径流,仅为农耕地径流小区的1/28～1/5,3种植被恢复模式小区的1/4～1/2;各小流域径流模数和侵蚀模数与降雨量呈显著正相关,径流模数与侵蚀模数之间亦呈正相关;产沙量的多少与小流域径流面积关系不大,但不同小流域之间的侵蚀模数随着降雨量的增加,其差别有减小的趋势。不同恢复阶段和不同恢复阶段一次性降雨的产沙量和侵蚀模数与初期相比都呈现出明显的减小趋势,特别是在植被恢复的最初几年,其减沙的效应就达到70%以上,表明植被恢复初期是体现水土保持效应的关键时间。
Through the study on the impact of vegetation restoration on the runoff and sediment yield in the small watershed in the seriously degraded area of Jialing River, the results show that the channel erosion modulus of each small watershed is lower than that of the slope runoff, only 1/28 ~ 1/5 And 1/3 to 1/2 of the three vegetation restoration patterns. The runoff modulus and erosion modulus of each catchment showed a significant positive correlation with rainfall, and the correlation between runoff modulus and erosion modulus was also positive. The sediment yield And the runoff area of small watershed has little to do with it. However, with the increase of rainfall, the difference of erosion modulus between different small watersheds tends to decrease. Sediment yield and erosion modulus of one-off rainfall in different restoration stages and different recovery stages showed a clear decreasing trend compared with the initial stage, especially in the early years of vegetation restoration, the effect of sediment reduction reached 70% The above shows that the initial period of vegetation restoration is the key time to reflect the effect of soil and water conservation.