晋西北人工林土壤水分特点与降水关系研究

Study on Characteristics of Soil Water of Planted Forest and Its Relation to Precipitation in Northwestern Shanxi

根据１９８８１９９０年和１９９２１９９５年共７年的定位观测资料，对晋西北黄土丘陵沟壑区河北杨林、柠条灌木林的土壤水分特点进行了分析。结果表明：晋西北不同人工林的土壤水分季节动态变化规律基本一致，主要受降水量及其分配的影响。一般年份６月以前为土壤干季，７月土壤湿季开始，但在偏旱年份，出现土壤湿季在前、干季在后的情况。土壤水分垂直动态变化的差异，表现为林地土壤水分上部大于下部，绝大多数年份，土壤水分随深度增加而减少。不同水文年土壤水分的年循环水平及生长期末的土壤贮水量与降水量有关，以土壤贮水量与降水量的关系最为明显。

Based on the field measured data of seven years from both 1988 to 1990 and 1992 to 1995, the relationship between soil water of Populous hopeiensis, Caragana korshinskii plantations and precipitation in the loess plateau region of northwestern Shanxi province was studied. The results were as follows:The seasonal change of soil water characteristics was the same in different plantations in growing season, and controlled mainly by precipitation and its distribution. Generally speaking the period from April to June was soil dry season; July to October was soil wet season. But in the dry and extra dry year opposite result occured. Compared with uncultivated land, the profile change of soil water in plantations showed that soil water content in surface layer is bigger than that in middle layer and in under layer. The correlation between the cycle level of soil water, stored soil water at the end of growing season in different rainwater year and precipitation of growing season was significant respectively. The both consumption and compensation of soil water also were controlled by precipitation and its distribution.