晋西黄土区刺槐林地土壤水分对降雨的响应  

Response of soil moisture to precipitation in Robinia pseudoscacia forestland in loess region of western Shanxi Province,northern China.

作　　者：鲍彪[1] 毕华兴[1,2] 云雷[1] 高路博[1] 许华森[1] 安云[1] 

机构地区：[1]北京林业大学水土保持学院水土保持与荒漠化防治教育部重点实验室 [2]山西吉县森林生态系统国家野外科学观测研究站

出　　处：《北京林业大学学报》2012年第2期84-89,共6页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(30972419)

摘　　要：通过野外坡面降雨试验,对晋西黄土区刺槐林地内土壤水分进行连续定位观测,以揭示晋西黄土区坡面土壤水分对降雨的响应,旨在为黄土高原区水土流失治理提供一定的理论依据。结果表明:1)坡面土壤含水率受植被密度影响较明显,密度较高的刺槐林地相对于密度较低的林地或裸地而言,其林地内坡面土壤水分对降雨的响应较平缓。2)垂直方向上,0～20cm土层土壤含水率对降雨的响应最为直接和迅速。植被密度不同,各测点次表层(10～20cm土层)土壤含水率的上升有先后之分,与表层(0～10cm土层)相比,次表层的土壤含水率变化有一定的滞后和延长,体现出土壤水分入渗的先后过程。深层(20～150cm土层)土壤含水率对降雨几乎无响应过程。3)坡面上表层土壤含水率对降雨的响应受降雨强度和植被密度影响,当降雨强度较小时,土壤含水率变化会出现上升期和退水期;当降雨强度较大时,土壤含水率变化则分为上升期、平台期和退水期,各期到达时间会因植被密度增加而出现相应的滞后现象。In order to provide some theoretical basis for controlling water and soil erosion on the Loess Plateau, the process of soil moisture responding to precipitation in the loess region of western Shanxi Province was studied through a series of field slope rainfall experiments. In the experiments, the soil moisture in the loess region of western Shanxi Province was continuously positioning observed. The results showed that： 1） slope soil moisture content was obviously affected by the density of vegetation. Compared with the forest with low vegetation density or bare land, the response of slope soil moisture to precipitation in the forest with high density was comparatively gentle. 2） In vertical direction, the response of soil moisture content to precipitation was most direct and rapid in the layer ranging from 0 to 20 cm. With varied vegetation density, the soil moisture content of subsurface （10-20 cm） of each measuring point increased sequentially. Compared with the surface layer（0-10 cm） , the curves of soil moisture content rising in subsurface were delayed and extended, reflecting the successive process of soil moisture infiltration. The response of soil moisture content to precipitation in the deeper layer （20-150 cm） was almost non- existent. 3） The response of soil moisture content to precipitation in surface layer on the slope was affected by rainfall intensity and vegetation density. When the rainfall intensity was low, the variation process of soil moisture content can be divided into two periods： rising and decreasing; while when rainfall intensity was high, the process exhibits three periods： rising, steady and decreasing. The arrival time of each period lagged with the vegetation density increasing.

关 键 词：晋西黄土区 刺槐林 土壤水分 降雨 

分 类 号：S714.7[农业科学—林学]