黄土丘陵区不同植被下土体入渗性能研究

The Comparing Study on Soil Infiltration of Vegetation Land in Hilly Area of Loess Plateau

采用PVC管在野外刺槐林，沙棘林，荒草地3种植被类型下取原状土，土层深度分为0～30cm，30～60cm，O～60cm三个层次。将土柱放回室内，采用无压力的供水入渗装置测定土体的入渗性能。对每个土体的入渗过程进行连续跟踪，测定土体底部稳定出水率，以此定为该土层深度的稳渗率。同时提出以土层深度界定稳渗率，并指出低入渗层对一定土层的入渗影响。研究结果表明：原状土的入渗性能远大于扰动填装土；不同植被间入渗性能差异很大，同一植被类型不同土层深度入渗性能差异显著，表层土的入渗结构好于心土层等等。

The original soll was got by PVC tube in Robinia peudoacacia, Hippophae rhamnoides,and grassland three forest vegetations, soil depth includes 0～30 cm,30～60 cm,0～60 cm. Put the original soil in the room,the special supply water device was used to determinate soil infiltration, which haven＇t splash erosion and pressure head. Processes of Infiltration about all soil columns are tracked continuously; the steady infiltration rate is represented by steady outflow from the bottom of soil columns. At the same time,it proposed that the steady infiltration rate should be defined by the soil depth, and also proposed the influence of infiltration choke points on a given soil depth. The results showed that the capability of original soil infiltration is greater than disturbed soil; diversity of infiltration is great in different forest types, which is also significant in the same forest types but different soil depths the capability of original soil infiltration on top soil is greater than bottom soil, and so on.