三峡库区典型森林植被类型对坡面产流影响

The Impact of Typical Forest Vegetation Types on Slope Runoff in Three Gorges Region

在一定地形地貌基础上，植被与降水是决定坡面产流、产沙量的主要因素．2005～2006年对重庆缙云山4个天然林地径流场和农地径流场进行定位观测，结果表明：①森林植被在一定范围内对坡面径流量有削减作用，前期降雨对坡面径流有影响；②坡面径流峰值与暴雨峰值呈一一对应关系，马尾松和常绿阔叶林的变化幅度较小，柏竹林和常绿阔叶灌丛变化较大；③地下径流深与降雨量呈一一对应关系，地下径流深与降雨量关系反映出前期降雨对地下径流量的影响；④马尾松阔叶混交林、常绿阔叶林和常绿阔叶冠丛地下径流峰值的总体趋势是随降雨强度的增加而增加；楠竹林和农地随降雨强度的增加而呈下降趋势．

The vegetation and precipitation are the major factors which determine runoff and sediment yield on the basis of certain terrain. The fixed observation on runoff ground in farmland and 4 runoff grounds in natural forestland had been conducted in Mt. Junyunshan in Chongqing from 2005 to 2006. The results showed that forest vegetation could decrease surface runoff to some extent, and rainfall had impact on slope runoff in earlier stage; the slope runoff peak flow corresponded to rainfall intensity, the runoff change range of Masson Pine and evergreen broadleaved forest was comparative small, while that of bamboo forest and evergreen broadleaved shrub was big; underground runoff depth corresponded to rainfall, which reflected prophase rainfall had impact on underground runoff; the general trend of mixed coniferbroadleaved forest, evergreen broadleaved forest and shrub was that it increased with rainfall＇ s increasing, but bamboo forest and farmland deceased with rainfall＇ s increasing.