摘要
根据乌兰布和沙漠东北缘的自然环境特点和植物生理生态特征,基于水量平衡原理建立土壤水分动态模型,模拟计算该区植被在不同叶面积指数下的土壤水分动态变化和保证植物生存前提下的土壤水分亏缺值,评价该区土壤水分植被承载力。结果表明:自然条件下乌兰布和沙漠东北缘土壤蒸发占降水的比例在流动沙地和半固定沙地大于60%,固定沙地为44.8%;在叶面积指数低于1.7 m2.m-2时,土壤水分亏缺水平较低,叶面积指数继续升高时,土壤水分亏缺大幅度增加。从而确定该区土壤水分植被承载力为叶面积指数1.7 m2.m-2。
The water dynamics in soil with different leaf area indexes and the soil water deficit value in the prerequisite to assure the plant survival were simulated and calculated using the dynamical soil water model based on the water balance theory, the characteristics of the environment and the physiological ecology of the plants in the Ulan Buh Desert, and the soil water carrying capacity of vegetation in the area was estimated. The results showed that the proportion of the soil evaporation was more than 60% of the precipitation in wandering and semi-fixed sands, while it was 44.8% in fixed sand. When the leaf area index was less than 1.7m^2·m^-2, the soil water deficit remained in a lower level, while when the leaf area index continuously increased, the soil water deficit increased rapidly. It was concluded that the leaf area index of the soil water carrying capacity of vegetation was 1.7m^2·m^-2 in this area.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2008年第9期13-19,共7页
Scientia Silvae Sinicae
基金
国家自然科学基金重点项目(30230290)
