晋西黄土区水土保持林水量平衡的研究

Study of the Water Balance for Soil and Water Conservation in Forests of Northwest Shanxi Province

用水量平衡法研究了晋西黄土区水土保持林的水量平衡,并制定了水量平衡表,用干旱危险系数作为指标评价了水土保持林地的水分动态.研究表明:黄土区林地地表径流很少,达到可以忽略不计的程度,系统的主要支出项为蒸发散量.因此,要充分发挥水土保持林的效益,必须降低林分的蒸发散、抑制林地蒸发,即减小造林密度.

This paper concerns the water balance in a forest for soil and water conservation in northwest Shanxi province and provides a table of water balances for different stands.The paper also presents a dry coefficient,which is used to evaluate soil moisture.It is shown that there is very little surface runofi,and the main water loss is by evapotranspiration.In order to improve forest soil and water conservation,we should reduce the stand density to decrease evapotranspiration.