FANG Sheng1, 2, 3, PENG Tao1, 2, WANG Shi-jie1, 2, LIU Xiu-ming1, 2, MENG Fan-de1, 2, 3
( 1.The State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002,China;
2. Puding Karst Ecosystem Research Station, Guizhou, Puding 562100, China;
3. University of Chinese Academy of Sciences, Beijing 100049, China)
Abstract: To find out the spatial variation of soil steady-state infiltration rates in karst hillslopes, the spatial distribution and soil properties of four habitats (soil surface, soil-rocky surface, rocky gully, and stone crevice) were investigated along six karst hillslopes with typical human activities. The soil steady-state infiltration rates were measured by means of a Guelph Permeameter. The statistical results show that: 1)the soil steady-state infiltration rates of karst hillslopes are obviously high as compared to non-karst regions, and mainly controlled by soil porosities and cracks of Epikarst coupling; 2) the soil steady-state infiltration rates of four habitats show high spatial heterogeneity and “patch shape” spatial characteristics in karst hillslopes; and 3) transfer of human activities will modify soil properties of habitats, and then change the steady-state infiltration rates. The soil steady-state infiltration rates of soil surface and soil-rocky surface are higher than those of rocky gully and stone crevice in original forest, young forest and mixed arbor and shrub forest with smaller human influence. Soil bulk density and clay proportion of soil surface and soil-rocky surface increase seriously and contrary soil porosity and steady-state infiltration rates significantly decrease when the hillslopes are transformed to burned forest or pastureland. Under the same condition, soil properties and steady-state infiltration rates of rocky gullies and stone crevices affect less significantly than the soil surface and soil-rocky surface habitat, which still have high soil steady-state infiltration rates.
Key words: karst; soil; water infiltration; soil steady-state infiltration rate; heterogeneity; land use.
EARTH AND ENVIRONMENT Vol. 42, No.1, Tot No.297, 2014, Page 1-10
