晋西黄土残塬沟壑区不同植被类型土壤水分动态研究

采用时域反射仪（TDR）于2005年在晋西蔡家川流域对刺槐、油松等8植被类型样地进行了土壤水分动态研究，研究结果表明:在2005年，0~200 cm土壤水分含量平均值变化过程除农地外，不同地类土壤水分变化特征差异性小，研究期内土壤水分日平均值按从大到小排列顺序为:农地、侧柏、次生林、油松、果园、刺槐×油松、刺槐×侧柏、草地、刺槐；在季节变化中，可将其分为三个时段:土壤水分消退期、土壤水分稳定期、土壤水分积累期。人工林与果园、农地、草地、次生林相比土壤水分调节作用较强；在日尺度上各样地土壤水分受降雨量及降雨分布影响。在样地土壤水分剖面垂直变化上土壤的剖面结构分为土壤水分弱利用层、土壤水分利用层、土壤水分调节层；农地、次生林、油松、侧柏、侧柏×刺槐、草地、果园土壤水分含量随深度变化趋势属于增长型；刺槐、刺槐×油松属于减少型。

Study on Dynamic Changes of Soil Water of Different Vegetation Types on the Loess Plateau of Western Shanxi Province

In 2005,adopt TDR carry on the soil humidity dynamic state research on 8 vegetative types at Caijiachun watersheld in west Shanxi Province.The result indicates that:in 2005,the characteristic of variety process of the average soil humidity in the range of 0～200 cm has small differences among the sites except farmland.During the growing season,different vegetations can be arranged in the high-to-low order of soil humidity as: farmland,Platycladus orientalis,secondary forest,Pinus tabulaeformis,orchard,Robinia pseudoacacia×Pinus tabulaeformis,Robinia pseudoacacia×Platycladus orientalis,grassland and Robinia pseudoacacia.As to seasonal variation,divide the growing season into three periods: lessen period,stable period and compensatory period.Compared with orchard,farmland,grassland and secondary forest,artificial forest has stronger effect in improving soil moisture condition.In diurnal changes,soil moisture content of all of the sites are affected by rainfall and distribution.According to soil humidity vertical variation,the soil profile can be divided into three layers: weak utilization layer,utilization layer and regulating layer.As to the soil moisture content variety trend,Farmland,secondary forest,Pinus tabulaeformis,Platycladus orientalis,pseudoacacia×Platycladus orientalis,grassland and orchard are increment pattern;Robinia pseudoacacia and Robinia pseudoacacia×Pinus tabulaeformis,Robinia are decline pattern.