典型喀斯特灌丛草坡类型区土壤水变化规律研究

Research on Soil Moisture in the Typical Shrub-grass Zone in Karst Regions

以贵州省红枫湖、龙里灌丛草坡类型区为定位研究区域,选取灌丛、草地和玉米地3种植被类型,利用长时间序列的观测资料,研究了喀斯特地区石漠化过程中重要过渡类型——灌丛草坡的土壤水分变化规律。(1)不同的植被覆盖类型,土壤水分变化规律也不同。从降雨过后初始含水量大小来看,玉米地>灌丛>草地;从递减率来看,玉米地>灌丛>草地;(2)草地土壤水分递减速率小于灌丛,其保水性强,因此,典型喀斯特地区草地植被生态与其它地区不同,呈现出一种"自适应性"现象。

The study area is located in the shrub-grass zone, Longli County, Guizhou Province. Based on long-term data and hydrological methods, soil moisture capacity is studied in views of its temporal and spatial patterns and dynamic characteristics. Different types of vegetation cover have different forms of soil moisture movement. Shrub land, grass land and corn field are selected for comparison. Land types rank in the descendant order of corn field, grass land and shrub land in terms of the initial content, whereas they rank in the descendant order of corn field, shrub land and grass land in terms of the descending rate. The analyses of soil moisture indicate the descending rate of the soil moisture on grass land is slower than that on shrub land, and their water retention property is stronger. Vegetation on grass land is different from other regions, and appears to be adaptable.