石砾对土壤水分常数的影响

Impact of Gravel on Soil Moisture Constants

本文以四川盆周山地常绿阔叶林地土壤为研究对象,分析了石砾对土壤水分常数的影响;同时针对砾质土的特点,对土壤容重的定义进行了补充和完善。结果表明:对于砾质土的土壤,样本间水分常数的测定结果重现性较差,变异较大;石砾含量在一定范围内,可增加土壤孔隙数量,提高土壤的入渗率,但使土壤结构的水稳性降低;当石砾含量超过10%,土壤中有效水分数量将随石砾含量的增加而减少;在地表植被不被破坏时,多砾质土壤发生地表径流的可能性极小,存在入渗过速导致养分的流失和水分的流失问题;与非砾质土相比,砾质土在测试、计算和评价方面都有其特殊性。

In this paper, an analysis is made of the influence of gravel on the soil moisture constants of evergreen broad-leaved forests in mountain areas of the Sichuan Basin. The definition of soil bulk density is revised according to the character of gravel soil. The results have indicated that the water moisture constant of gravel soil is not constant, and has a great variation. Gravel of the forest soil can increase the number of soil pore space and infiltration rate, however, will reduce the stability of soil structure. When the content of gravel in the soil is greater than 10%, the amount of saturation water capacity and capillary water capacity and available soil water will decrease with the increase of gravel content. If the vegetation is not destroyed, the occurrence probability of runoff of soil surface will become less for gravel soil, but will cause questions of the loss of nutrient and water because of fast infiltration. Gravel soil is of particularity in the aspects of testing, computing and evaluating.