黄土高原寒区青海云杉人工林地土壤水分物理特性研究

Study on Physical Characteristics of Soil Moisture of Picea crassifolia Plantation in Loess Plateau Region

对黄土高原高寒区的青海云杉人工林林地的土壤水分物理性质进行了实地观测和分析(主要采用野外实测土壤水分再分布的方法,对入渗后不同土层土壤的水分再分布过程及低吸力段土壤水分特征作了研究),发现该林地在枯落物及林下植被层的作用下,使得0～10cm表层土壤的持水性最好;因放牧践踏导致林地10～30 cm土层的土壤板结密实,持水性较差;30～50 cm土层土壤的持水性居中.通过研究还拟合得出了该林地土壤水分再分布、土壤水分特征曲线及土壤比水容量的参数.为该地区退耕还林还草、林业生态建设和森林水文效益评价提供了可靠依据.

The physical characteristics of soil moisture of Picea crassifolia plantation in loess plateau region were insite observed and analyzed. Using the methods of in-site measuring re-distribution of soil moisture, the process of soil moisture re-distribution in different soil layer and the water characteristics in low suction conditions were studied. The results showed that with the function of litter and undergrowth, the surface soil （0-10 cm） had the best water retention capacity, the soil in layer from 10 cm to 30 cm was compact because of grazing with low water retention capacity, and the water retention capacity of soil in 30 cm to 50 cm was medium. The parameters of soil water re-distribution, soil water curve and soil water capacity were worked out. This study provided some dependable data for conversion of cropland to forest and grassland, forestry ecological construction and forest hydrological effect evaluation in loess plateau region.