黄土丘陵半干旱区典型人工林土壤水分特征

在黄土丘陵区选取不同林龄典型人工乔木林刺槐,灌木林沙棘、柠条,并以经过30 a多自然演替形成的荒坡草地作为对照,研究了人工林地土壤水分特点.结果表明,(1)人工林地总体持水能力较差,不同类型林地土壤持水能力顺序:刺槐林>沙棘林>柠条林,随着林分的生长,土壤持水能力均有增强的趋势;(2)土壤的导水能力随着林龄的增加有明显提高,林龄较接近时,刺槐林较沙棘林和柠条林饱和导水率大;(3)随着林分生长,林地土壤饱和含水量值增大,林地蓄水能力增强;(4)与荒坡对照相比,人工林改善土壤持水、导水能力的效果不一定有生态系统自我修复作用形成的植被群落好.

Soil Water Characteristics of Artif icial Forest Lands in Loess Hilly Region

The soil water characteristics in typical artificial forest lands ( Robinia pseudoacacia, Hippophae rhamnoides, and Caragana intermedia) with different ages and the slope grassland as contrast in the loess hilly region are studied. Results show that (1) soil water holding capacity in artificial forest lands is low and by soil water holding capacity, the artificial forest lands have the order of Robiniapseu doacacia > Hip pop hae rhamnoides > Caragana intermedia. Soil water holding capacity increases as the age increases. (2) Soil water conductivity increases significantly as the age increases and saturated hydraulic conductivity in Robinia pseudoacacia land is higher than that in Hip pop hae rhamnoides and Caragana intermedia lands at the matured stage. (3) The increase in the saturated soil water content is found with the increase in age. 4) Soil water holding capacity and conductivity in the artificial forest lands are not better than those in slope grassland repaired by itself .