大别山区典型植被措施坡面产流产沙对降雨特征的响应OA

[Objective]This study aims to clarify the regulation mechanisms of different vegetation types on slope erosion under complex rainfall patterns in the Dabie Mountain Region,and to investigate the effects of rainfall types,vegetation species,and their interactions on slope runoff and sediment yield,so as to provide a scientific basis for soil and water conservation and vegetation restoration in this region.[Methods]Based on data from 59 erosive rainfall events from 2007 to 2016 recorded at runoff plots of the Shiqiaopu station in Huanggang City,Hubei Province,China,the K-means clustering method was employed to classify the rainfall events into three types(A,B,and C)according to three parameters:precipitation,rainfall intensity,and duration.The characteristics of runoff and sediment yield under different rainfall types and vegetation species were investigated,and the factors influencing slope runoff and soil loss were analyzed.[Results]Type C rainfall(low precipitation,moderate duration,low intensity,frequency 58%),although weak in individual events,resulted in the largest annual cumulative soil loss due to its high frequency,with contribution rates of 55.0%and 74.3%to runoff and sediment yield,respectively,making it the dominant rainfall type in this area.Type B rainfall(high precipitation,long duration,high intensity,low frequency 8%)caused the greatest single-event damage,contributing 10.2%to runoff and 12.4%to sediment yield.Type A rainfall contributed 34.7%and 13.3%,respectively.Densely planted vetiver grass demonstrated the best soil and water conservation effect,reducing annual average runoff and sediment yield by 59.3%and 73.8%,respectively,compared with coreopsis(p<0.05).The overall soil and water conservation effect of the five vegetation types ranked as follows:densely planted vetiver grass>vetiver grass>daylily>Argentine senna>coreopsis.Correlation analysis showed that runoff(RY)was primarily driven by precipitation(P),while soil loss(SY)was closely related to runoff volume(RY)and rainfall erosivity(R).[Conclusion]Type C rainfall is the dominant rainfall type controlling annual runoff and sediment yield on yellow-brown soil slopes in the Dabie Mountain Region.Densely planted vetiver grass exhibits optimal ecological protection efficiency through a cascade regulation of rainfall-runoff-erosion.