乐都县上北山林区土壤贮水能力评估及建议

森林具有重要的水源涵养功能,通过测定森林土壤贮水量,可以反映森林土壤涵养水源的能力。本文通过对乐都县上北山林区土壤物理性质、土壤贮水量进行分析,初步探讨了乐都县上北山林区土壤的涵养水源功能。结果表明:上北山林区土壤容重和比重层状递增趋势明显;土壤最大持水量、毛管持水量、最小持水量、非毛管孔隙度及总孔隙度,具有愈往底层愈低的分布特征;土壤毛管孔隙度的层间分布特征较特别,上层稍大,底层最大;乐都县上北山林区的土壤总贮水量为2923.2万t,总最大持水量达43176万t,其贮水能力对湟水河的涵养作用是不容忽视的。

Assessment on Water Storage Capacity of Soil in Forest of Upper-North Mountain of Ledou County

Forest plays an important role in water conservation. Determination of water storage capaci- ty of soil reflects the capacity of water conservation of forest. Forest soil in Upper-North Mountain forest region was analyzed in terms of its physical property and water storage capacity. The result showed that soil bulk density and specific gravity tend to increase with the depth of soil layer. Maxi- mum water--holding capacity, capillary moisture capacity, least water-holding capacity , non-capillar- y porosity and general po/osity tend to be declining with the depth of soil layer. Capillary porosity in the layer appears biggest at the bottom. The total water storage capacity in Upper-north mountains forest region is 29,232,000 tons and the total maximum water holding capacity is 431,760,000 tons, which.