红壤丘陵区土壤渗透性及其受植被影响分析

Soil permeability and effects of vegetation in the red soil hilly region

选择中科院湖南桃源农业生态试验站典型覆被坡面作为研究对象,通过现场实验与野外采样分析,确定不同覆被的土壤饱和渗透系数及不同埋深的非饱和导水率曲线,分析红壤丘陵区土壤渗透性及其受植被的影响。结果表明,植被类型显著影响土壤渗透性能,其渗透能力由强至弱依次为原生林、油茶林、针叶林和恢复区裸地。不同根系特征土壤的入渗能力不同,根系愈发达渗透性愈好。由此也证明了所得到不同埋深的土壤非饱和导水率曲线的可靠性,为下一步红壤丘陵区生态水文模拟提供分析基础。

Typical red soil hillslopes with different vegetations at the Taoyuan Agr-ecology Experimental Station of Chinese Academy of Sciences were selected for the lab and field experiments on soil permeability. Soil saturated infiltration coefficients and un- saturated hydraulic conductivity curves at different soil depths were determined. Effects of vegetations on soil permeability in the red soil hilly region were also analyzed. Vegetation types significantly affected soil infiltration properties, and the order of vegeta- tions in terms of their impacts on soil permeability from strong to weak was primeval forest, camellia forest, coniferous forest, and bare soil in vegetation recovery area. Different vegetation root characteristics had varied influence on soil permeability. The soil with well-developed roots had higher soil permeability. The oil unsaturated hydraulic conductivity curves have been proved to be reliable. Our study offers insights into further eco-hvdrological modeling in red soil hilly regions.