岩溶石山区坡地土壤剖面水分与蒸发特征——以桂林丫吉试验场为例

选取桂林丫吉试验场岩溶石山坡面上典型覆盖土壤的两个单元体为对象,对其土壤剖面层含水量的分布变化、土壤蒸发速率大小及其相关影响因素进行分析研究,结果表明:(1)土壤剖面最大含水率层位于土壤底部与基岩的交界处,中间过渡层土壤含水量最少,表层土壤水分受外界因素影响而变化显著;(2)在夏季岩溶石山区地表蒸发强烈,直径10cm的土壤柱日蒸发量为5~12mL之间,夜蒸发量在0~3mL之间;(3)几天内决定地表土壤日蒸发量(y)大小的因素主要是太阳辐射(x2)和土壤温度(x4),其关系式可表示为:y=18.018+0.001x2-0.691x4。 

Characteristics of moisture and evaporation on slope land soil profile in karst stone hill: A case in the Yaji experimental site

Two typical covering soil units located in karst hill in the Yaji Experimental Site in Guilin are cho- sen as the research object to analyze the moisture distribution and evaporation rate as well as the related in- fluencing factors on soil profile. The result shows that （1）the soil maximum moisture content layer is located at the junction of the bottom soil and bedrock, the least moisture content at the middle transition layer soil, and the moisture content on the surface soil changes significantly with environments~ （2）evaporation is high in summer, with the amount up to 10 mL to 12 mL in 10 cm soil column by day and 0 mL to 3 mL by night; （3）the main factors determining the diurnal evaporation （y） in short terms include solar radiation （x2） and soil temperature （x4）,the equation is： y=18. 018＋0. 001x2--0. 691x4.