【摘要】 为了明确喀斯特峰丛洼地不同土地利用类型土壤水分对降水的响应,采用定位观测法,选择顺坡种植桂牧1号、顺坡种植玉米、封育、刈割除根、火烧、刈割6种喀斯特峰丛洼地最典型的土地利用方式,分析了这6种土地利用方式下土壤水分动态变化。结果表明:研究区2011—2013年的降水量可分为枯水年(2011年)、丰水年(2012年)和平水年(2013年)三种降水年型。枯水年土壤水分年均含量表现为种植桂牧1号>封育>刈割>火烧>刈割除根>种植玉米,平水年和丰水年均表现为封育>刈割>种植桂牧1号>火烧>刈割除根>种植玉米。封育和桂牧1号土地利用方式在各降水年型下均具有较高的水分含量,而种植玉米土壤含水量则最低,其次为刈割除根。降水年型对土壤水分变异系数的影响表现为枯水年>丰水年>平水年的趋势。不同土地利用方式在枯水年、丰水年和平水年三种降水年型中,土壤水分变化趋势各有特点,主要受近期降水和土壤蒸发的影响。封育和桂牧1号土壤水分含量高,两种土地利用方式能显著改善土壤水分状况,积蓄一定的水分。更多还原

【Abstract】 The purpose of this study was to clarify the response of soil moisture to precipitation in different land-use types.Based on the controlled experiment and long-term monitoring of six most common land-use types, i.e., burning, cutting,cutting plus with root removal, enclosure, maize plantation, and pasture of Guimu No. 1 plantation, the study was conducted to analyze the dynamic characteristics of soil moisture under these land-use types. The results showed that the annual precipitation of 2011-2013 in the study area could be divided into three types, i.e., dry year(2011), rainy year(2012) the normal year(2013). The variation of surface soil water content under different land-use types presented in the order of rainy year > normal year > dry year. The variation of surface soil water content was in the order of pasture of Guimu No. 1 plantation > enclosure > cutting > burning > cutting plus with root removal > maize plantation, while normal year and rainy year in the order of enclosure > cutting > pasture of Guimu No. 1 plantation > burning > cutting plus with root removal >maize plantation. Both enclosure and the pasture of Guimu No. 1 plantation under the three precipitation years had higher surface soil water content, while maize plantation had the lowest soil water content, and cutting plus with root removal followed. The effect of different yearly rainfall patterns on variance coefficient of soil moisture decreased in the order of dry year> rainy year > normal year. The monthly variation of surface soil water under different land-use types in three precipitation years(i.e., dry year, rainy year, and normal year) had their characteristics, which were affected by recent precipitation and soil evaporation. The soil moisture content was high in the enclosure and Guimu No. 1 plantation, which could improve the soil moisture status and accumulate water in the Karst area.更多还原