Study on the Characteristics of Preferential Flow of Typical Vegetation in A—C Structure of Soils on a Granite Hillslope
In the hilly area with A—C structure soil,the soil is thin and the rocks are abundant.It is not clear whether the preferential flow development under different vegetation conditions is affected by soil thickness and gravel content.In this study,the staining tracer method and image processing technology were used to study the spatial distribution of preferential flow staining profiles and its influencing factors in black pine forest,robinia forest(soil thickness about 40 cm)and chestnut forest(soil thickness about 80 cm)with different soil thickness.The results showed that the development depth of the substrate flow and the non-uniform coefficient of the maximum infiltration depth under different vegetation had no significant difference(P＞0.05).but the maximum infiltration depth,preferential flow ratio,length index under chestnut forest with thicker soil layer were significantly higher(P＜0.05).Therefore,the development degree of preferential flow was higher in the forest with thicker soil layer.The root length density,soil bulk density,total porosity,non-capillary porosity and gravel content are the important factors affecting the selection of preferred flow path under different vegetation conditions,but the changes in profile distribution of soil physical properties and root density was the key factors affecting the difference of preferred flow development under different vegetation conditions.The results of this study are helpful to further reveal the mechanism of preferential flow production in earth-rock mountainous areas.
preferential flowstaining tracerdyeing area ratiosoil thicknessvegetation type
万方数据
