作　　者： ; ; ; ;

机构地区： 中国科学院亚热带农业生态研究所

出　　处： 《水土保持通报》 2007年第5期32-36,共5页

摘　　要： 于2004年9月至2005年4月,对桂西北喀斯特峰丛洼地中耕地、牧草地和撂荒地3种利用类型的土壤水分进行定位观测,并研究了其受典型降雨过程的影响。结果表明,3种土地类型表层(0—20 cm)土壤含水量最低但波动最大,越到底层含水量增加且波动变小,根系吸收和蒸腾耗水等因素使得牧草地表层土壤水分小于耕地。典型降雨对土壤水分的影响十分明显,但各利用类型土壤含水量对降雨的响应时间有所不同。耕地和牧草地表层土壤水分含量均在雨后1 d就显著增加,底层在雨后6～8 d才达到最高;而撂荒地在雨后3 d的剖面(0—30 cm)土壤含水量就达到最大值。研究发现3种类型中牧草地表层土壤水分的时间稳定性最差。降水、土地利用(植被)和土壤质地是造成研究区土壤水分变化的主要因素。 Based on soil moisture data from September 2004 to April 2005, the dynamic change of soil moisture and the influence from a typical rainfall were analyzed under three types of landuse （cropland, grassland and black fallow） in the peak-cluster depression areas of karst region in Southwest Guangxi Province. Results showed that soil moisture in surface layer （0-20 era） was the lowest, but fluctuated violently in all layers. Down to deeper layers, soil moisture increased and became steady. Surface soil moisture of grassland was lower than that of cropland for the absorption and transpiration of grass. Soil moisture was obviously influenced by typical rainfall, but the time responses for three types of landuse were different. Surface soil moisture increased obviously in cropland and grassland one day after rainfall, whereas bottom soil moisture reached the peak value 6-8 days after rainfall. Soil moisture of the 0-30 cm layer in black fallow reached the maximum 3 days after rainfall. The time stability of soil moisture in grassland was the worst. Precipitation, land use types （vegetation）, and soil texture were the main factors influencing soil moisture in the area.

关 键 词： 喀斯特 峰丛洼地 土地利用 时间稳定性 土壤水分

领　　域： [农业科学] [农业科学]