干旱半干旱区不同林型人工林水源涵养能力比较研究

Comparative study on water conservation capacity of different forest types of artificial forest in arid and semi-arid area

通过引入模糊物元模型优化水源涵养能力估算方法,从而为研究区林分结构调整、水源涵养能力提升提供科学依据。运用欧式贴近度,以青海省大通县塔尔沟小流域6种不同林型人工林云杉×白桦混交林(YB)、云杉×青杨混交林(YQ)、云杉×落叶松混交林(YL)、云杉纯林(Y)、落叶松纯林(L)、青杨纯林(Q)作为研究对象,定量评价其水源涵养能力。结果表明:欧式贴近度大小排序为YB(0.794)>YQ(0.723)>YL(0.655)>Y(0.494)>L(0.416)>Q(0.270),欧式贴近度越大,该林分类型水源涵养能力更强。6种林型中,白桦×青杨混交林水源涵养能力最强,青杨林水源涵养能力最差。

Drought, as a natural phenomenon of abnormal regional water shortage, has a profound impact on the ecological environment. As the global climate changes and the frequency of abnormal climate events increases, the form of drought in my country will become increasingly severe in the future. The degree of forest canopy closure, forest density, tree species composition and age composition in this study area are extremely unreasonable, the structure and function of the plantation are single and the stability is poor, and problems such as pests, pests and rodents continue to appear. Due to the lack of tending management, the unadjusted structure of the initial timber forest has led to its low comprehensive ecological function. In order to ensure the long-term and stable ecological function of the forest, it is urgent to evaluate its water conservation function and regulate and manage it. This paper combines the fuzzy matter-element model and establishes an evaluation system consisting of 16 indicators including forest evapotranspiration, forest canopy water retention characteristics, soil physical properties, water retention characteristics, litter physical properties, and water retention characteristics. Evaluate the weight of different indicators and evaluate the water conservation capacity. In this paper, 6 different forest types in the Targou, Datong County, Qinghai Province, spruce × birch mixed forest(YB), spruce × green poplar mixed forest(YQ), spruce × larch mixed forest(YL), spruce Pure forest(Y), pure larch forest(L), and pure poplar forest(Q) are the research objects to quantitatively evaluate their water conservation capacity. The results show that the order of European closeness is YB(0.794)> YQ(0.723)> YL(0.655)> Y(0.494)> L(0.416)> Q(0.270). The greater the European closeness, the water source of this forest stand type. Stronger ability to conserve. Among the six forest types, the birch × poplar mixed forest has the strongest water conservation capacity, and the Qing poplar forest has the worst water conservation capacity. By assessing the water conservation capacity of forests, exploring the water balance of the basin, and paying attention to the hydrological effects of forests, it is of great significance for regulating the runoff of the basin and improving the local microclimate. In this paper, the fuzzy matter-element model is used to analyze and study the water conservation capacity of different forest types of plantations, and provide a scientific reference for the selection of local afforestation tree species, the improvement of forest water conservation capacity, the transformation of inefficient forests and the adjustment of stand structure.