不同草带覆盖位置条件下坡沟系统侵蚀产沙差异性

以坡沟系统单元为研究对象,利用室内降雨试验,结合三维激光扫描和微地貌分析技术,研究不同草带覆盖位置下坡沟系统侵蚀产沙差异性。结果表明:一些布设在合适位置的草带能够在p0.05水平上显著影响坡沟系统的径流量和产沙量。植被布设于坡面中下部比布设于坡面上部具有更好的水沙调控作用,植被布设于坡面长度60%时,径流量和产沙量分别减少7.35%和62.93%,直接拦沙功效优于蓄水减沙功效,水土保持功效达到最优。植被布设于坡面下部时,其侵蚀输沙过程的剧烈程度得到了缓解,植被调控侵蚀发育的作用体现。植被布设于坡面中下部时,下垫面仅有52%的区域发生侵蚀,其侵蚀输沙过程的剧烈程度明显减少,植被调控侵蚀作用有效限制了侵蚀发育。植被布设于坡面中部和中上部时,加剧了侵蚀的发育程度。研究结果有助于更好地理解植被优化配置。

Study on Difference of Erosion Sediment In a Slope-gully System Under Different Grass Strip Position

In this study, the unit slope-gully system was used as the object, using indoor simulated rainfall experiments, combined with three-dimensional laser scanning technology and micro topography analysis technology, the difference of erosion sediment under different grasss trip position was studied.The results showed that some rational grass strips(p<0.05) influenced both runoff and sediment yield in the slope-gully system. The regulation functions on runoff and sediment with the grass strip on the middle lower part of the slope were generally clearer than those with grass on the upper part of the slope. The optimal position for grass strips in the slope-gully system was identified as 60% of the slope length. In this location, the grass strips could effectively reduce the runoff and sediment by 7.35% and 62.93%, respectively. The water storage function of the grass strip was weak; however, its direct sediment interception function was more effective, the water and soil conservation function was optimal.When grass strip was planted in the lower part of the slope, the severity of erosion sediment transport processes was eased, and the effect of grass strip on erosion was reflected.When grass strip was planted in the middle lower part of the slope, only 52% of the underlying surface was eroded,the severity of erosion sediment transport processes was eased significantly, the regulation of vegetatione ectively controlled the erosion formation and development.When grass strip was planted in the middle part and middle upper part of the slope, extremely aggravated erosion development.The information of this study can be useful for better understanding the optimal vegetation pattern.