重庆市缙云山不同林分对坡面产流的影响

针对三峡库区理水调洪型植被的建设问题,在三峡库区重庆缙云山4种典型林分(混交林、阔叶林、楠竹林和灌木丛)建立坡面径流小区,对天然降雨过程和由降雨产生的地表径流进行观测.结果表明,不同林分地表径流量的平均值,从大到小依次为楠竹林、阔叶林、混交林和灌木丛,分别是3.094,1.972,1.751和1.170 mm.混交林、阔叶林和灌木林的林地地表径流量,均小于楠竹林的地表径流量,且三者之间差异不显著.不同林分地表径流量与降雨量存在显著的相关关系,与降雨强度关系不显著.在同一降雨条件下,不同林分地表径流变化趋势存在一定差异,且均是楠竹林地表径流量最大.因此,重庆缙云山不同林分中,灌木丛理水调洪功能最强,楠竹林理水调洪功能最差.

Effect of Different Vegetation Types on Runoff Generation of Slope Land in Jinyun Mountains of Chongqing City

To study the effects of different vegetation types on runoff generation on slope land in the Three Gorges reservoir area of the Yangtze River, 4 standard runoff plots with different vegetation types were laid out in the J inyun Mountains, Chongqing City. The different vegetation types included mixed broadleaf-conifer forest, broadleaved forest, Phy l lostachys pubescens forest, and shrub. Rainfall and surface runoff from the plots were measured. Results show that vegetation types, in terms of the averaged value of surface runoff depth, were ranged in the order of Phy l lost achys pubescens forest > broadleaved forest > mixed broadleaf -conifer forest > shrub. Surface runoff depths for the vegetation types are found to be 3.094, 1.972, 1.751, and 1.170 mm. The amount of surface runoff in selected arbor forestlands is smaller than that in Phy l lost achys pubescens forest and significant difference in the amount of surface runoff does not exist in mixed broadleaf-conifer forest, broad2leaved forest, and shrub. The correlation between rainfall amount and surface runoff in forestlands is significant and the correlation between rainfall intensity and surface runoff in forestlands are not notable. Under the same rainfall condition, the variation tendencies of surface runoff in these types of forestlands are different and the amount of surface runoff in Phyllostachys pubescens forest is always the largest.