商洛市水源涵养服务功能空间格局与影响因素

以商洛市为例,利用InVEST产水量模型和多年平均涵养水量模型,以参数本地化、实地率定和结果验证,对该区水源涵养功能的空间格局分异规律及其影响因素进行分析。结果表明：① 商洛市水源涵养总量为27.48×10⁸m3/a,水源涵养能力为324.85 mm。五大流域水源涵养功能依次为旬河>乾佑河>金钱河>丹江>洛河。② 气候因素对产水能力空间格局影响最大,10 a土地利用变化和下垫面植被、土壤因素则对水源涵养空间异质性影响显著。③ 子流域单元产水能力相关性强的因子为多年平均降水、实际蒸散发和植物可利用水,水源涵养功能关键驱动因子是潜在蒸散量、土壤饱和导水率与森林覆盖率。

Spatial Pattern and Influencing Factors of Water Conservation Service Function in Shangluo City

As a major water source region of the of South to North Water Diversion Project, Shangluo City was selected as a case study. Water yield sub-model of the InVEST Model and Water Retention Model were used to reveal the spatial heterogeneity and influencing factor of the service of water retention. Through the process of in-situ acquisition, the field calibration and model verification, several conclusions were drawn as the following: 1) The gross amount of water conservation was 2.748×10⁹m3/a, and the capacity of water conservation was 324.85 mm in Shangluo City. The order of the capacity of water conservation of five watersheds was the Xunhe River, the Qianyou River, the Jinqian River, theDanhe River and the Luohe River. 2) Climate factors had the greatest effect on the spatialpattern of water yield capacity, and the land use change in recent 10 years and vegetationand soil properties in different underlying surface impacted significantly on the spatial heterogeneity of water conservation. 3) There was probably a stronger correlation among the space of water yield capacity and mean annual precipitation, actural vaporation, and the effect of plant available. The key driving factors of water conservation function was potentialevaporation, soil saturated hydraulic conductivity and forest cover rate.