六道沟流域典型坡面不同土地利用方式下土壤水分动态变化研究

Studies on dynamic changes of water contents of soil under different land uses in Liudaogou basin

以黄土高原水蚀风蚀交错带六道沟小流域典型坡面为研究对象,分析了雨季不同土地利用方式下土壤水分的动态变化。研究结果表明:雨季不同土地利用方式下不同测定时期土壤储水量的变异程度为退耕苜蓿地>荒地>退耕林地>农田,均为弱变异;土壤含水量在垂直剖面方向均存在显著差异,随土层深度的增加都呈现出减小趋势,且变异程度为荒地>退耕林地>退耕苜蓿地>农田;沿坡长方向从坡顶到坡脚土壤含水量和生物量的变化呈波浪状,且生物量波峰基本与土壤水分波谷相对应,这说明较高的植被生产力消耗较多的土壤水分。

Based on a case study of a slope in the wind-water erosion crisscross region on the Loess Plateau, the dynamic changes of soil water under different land uses were analyzed during the rain season. The results show that the variation of 0- 300cm soil water storage of four types of land uses are different, ranking in following order： degraded alfalfa land 〉 wasteland〉 degraded woodland〉 farmland, with a weak spatial variability. The decreasing tendencies of soil water in a soil profile with the increase of the depth are obviously different among the different land uses, the order of the variability is as follows： waste land〉 degraded woodland〉 degraded alfalfa〉 farmland. The soil water content and the plant biomass fluctuate along the slope from the top to its bottom showing that better vegetation consumes more soil water.