广西桂林不同植被覆盖下土壤含水量空间变异性研究

摘要

In the experimentation fields at Guilin Academy of Agricultural Sciences ,the soil (0-6 cm in depth) on the plot ,where soybeans ,sugarcanes ,or peartrees was gown ,was sampled to study the variation and spatial distribution of its water content .The results showed that (a) rainfall was the key factor affecting the water content in the surface soil ;(b) tillage affected the overall water content to a certain extent ;(c) the water content in the soil of the pear tree plotwas the highest ,followed by that of the sugarcane field ,and the soybean lot had the lowest water content in soil ;(d) the spatial distributions of water content in these areas ,which varied onmoisture levels , hada moderate degree of spatial correlation ;(e) the spatial distributions of water content in soilwere affected by the rainfall ,and also human factors in varingdegrees ;and (f) the vegetation coverages and artificial disturbances were factors in the spatial variability of the water content in the soils ,however ,since the distribution at localities with relatively high water levels were stable , the soil might be able tomakenecessary adjustments by itself . The information obtained could benefit studies ondrought prevention for agricultural lands ,irrigation for farming ,and management for reducing soil erosion in the karst regions in the province .%以桂林市农业科学院的大豆地、梨树地、甘蔗地为例，分析3个试验区土壤表层0～6 cm土壤含水量变化规律以及空间分布特征。结果表明：降雨是影响土壤表层土壤含水量变化的关键因子，耕作方式也在一定程度上影响土壤含水量变化，梨树地土壤含水量是三者之中最高，甘蔗地土壤含水量次之，大豆地土壤含水量最小；3个试验区在3种不同土壤水分状态下的土壤含水量空间分布属于中等程度的空间相关性，受降雨因素和人为因素共同制约，在不同条件下他们各自占有的权重不同；尽管不同的植被覆盖条件以及人为因素干扰会影响土壤含水量空间分布，但是土壤含水量较高的区域相对稳定，表明土壤本身具有恢复其空间分布稳定性能力。