秦岭火地塘林区3种土地利用类型的土壤潜在水源涵养功能评价

为了研究秦岭火地塘林区松栎混交林土壤的潜在水源涵养功能,以荒草地和农用地2种土地利用类型作为对照,于2011年5月在3种土地利用类型的样地上挖掘土壤剖面,并对其土壤物理性质和蓄水、入渗能力进行了分析,最后运用坐标综合评定法首次对该地区3种土地利用类型的土壤潜在水源涵养能力进行定量评价。结果表明:3种土地利用类型的土壤密度由大到小为荒草地(1.25 g/cm3)＞农用地(1.22 g/cm3)＞松栎混交林地(0.82 g/cm3),土壤总孔隙度由大到小为松栎混交林地(87.40%)＞荒草地(45.87%)＞农用地(38.95%);松栎混交林地土壤的蓄水性能和渗透性能最好,农用地最差。运用坐标综合评定法对3种土地利用类型进行评价,结果表明:松栎混交林地土壤的潜在水源涵养功能最佳(0.00),农用地土壤的潜在水源涵养功能最差(1.10),建议在该地区继续实施退耕还林以提高土壤的水源涵养能力。本研究为认识和综合评价火地塘林区松栎混交林的生态服务功能积累了基础资料,从而为南水北调中线工程的水源保障措施提供了一定的理论基础。 

Evaluation of potential water conservation function of the soil of three land use types in Huoditang of Qinling Mountains,northwestern China

In order to study the potential water conservation function of the soil of pine-oak mixed forest, the profiles were dug on the plots of three land use types in May of 2011 , with the grassland and farmland as contrast. Then the soil physical properties, water-holding capacity and infiltration capacity were analyzed, and the potential water conservation capacity of soil was quantitatively evaluated by the method of comprehensive coordinate. Results showed that the order of soil bulk density from high to low was grassland (1. 25 g/cm3) >farmland (1. 22 g/cm3) >pine-oak mixed forest land (0. 82 g/cm3). The rank of soil total porosity from high to low was pine-oak mixed forest land ( 87. 40%) > grassland (45. 87%) >farmland (38. 95%) . The pine-oak mixed forest land had the best water-holding capacity and infiltration capacity, and the farmland had the worst. The result using the method of comprehensive coordinate showed that the potential water conservation function of the soil of pine-oak mixed forest land was the best while the farmland was the worst, suggesting that the Reversion of Farmland to Forest Program should be kept on so as to raise the soil water conservation capacity in this region. This study provides basic data for cognizing and comprehensively evaluating the ecological service function of the pine-oak mixed forest in Huoditang forest region of Qinling Mountains, northwestern China, and offer theoretical basis for the water source protection of the Project of Diversion of Water from South to North.