Forest ecosystem services and their valuation of Ningxia area | 宁夏森林生态系统服务功能的价值研究

صينى. 对宁夏回族自治区森林生态系统的多种生态功能及其价值进行研究和评估，为宁夏林业可持续发展与生态环境建设政策的制定，以及国家宏观决策提供科学依据。综合运用替代工程法、市场价值法、费用替代法和机会成本等方法，对宁夏森林生态系统的涵养水源、保育土壤、固碳制氧贮养、净化大气环境、保护生物多样性、森林景观游憩与生态文化等生态功能及其价值进行评估。宁夏回族自治区2003和1998年森林资源清查时，森林生态系统服务功能总价值分别为425 611.069 1和459 976.917 9万元/年。 2次森林资源清查期间，主要服务功能的实物量及其价值量排序依次为：生物多样性保护、涵养水源（1998年涵养水源的价值略大于生物多样性保护）、固碳制氧贮养、保育土壤、净化大气环境、森林景观游憩与生态文化价值。2003和1998年不同植被类型的平均单位面积生态服务功能价值排序差异不大，依次为桦木＞栎类＞油松＞杨树＞椴树类＞云杉＞华山松＞落叶松＞软阔类＞硬阔类＞经济林，惟一不同的是2003年林种结构中多了柏木，而柏木单位面积所产生的价值是所有林种中最大的；2003年森林资源清查时平均单位面积林地的生态服务功能价值较1998年降低7.54%。在6种服务功能中，保护生物多样性能提供最大的价值，柏木生态系统所能提供的平均单位面积生态服务功能价值大于其他植被类型。

إنجليزي. Various ecological functions and valuations of different forest ecosystems in Ningxia Hui Autonomous Region was researched in this article to provide basic data for the green GDP accounting and assessing the whole country’s forest ecosystem services, and to supply a scientific basis of sustainable development of forestry and policy-making for ecological environment. Methods such as shallow engineering method, production cost method, substitute method and opportunity cost method were used to evaluate forest ecosystem services including water conservation, soil conservation, carbon fixation, oxygen released and nutrient accumulation, atmosphere purification, biodiversity protection, forest recreation and eco-tourism in Ningxia area. The results indicated that: (1) The annual integrated value of forest ecosystem services in 2003 and 1998 were respectively 425 611.069 1 million yuan and 459 976.917 9 million yuan; (2) The physical quantities and value of main service functions were sequenced as biodiversity protection, water conservation, carbon fixation and oxygen making, soil conservation, environment purification, forest recreation and eco-tourism; (3) In 2003 and 1998, among different vegetation types, birch had the highest economic value of service function per unit area, followed by oak, Chinese pine, polar, linden, spruce, pinus armandi, larch, soft broad-leaved trees, hard broad- leaved trees, economic forest. The only difference between these two years was cypress, the largest service value among all forest types, which increased in 2003. To sum up, the value of biodiversity protection is higher than any other five service functions, which provide the importance of biodiversity protection to ecosystem services. From the view of vegetation types in the whole area, cypress provides the largest service value of ecosystem of service function per unit area among all vegetation types, which can supply very important guidance for restructuring of forest types in next period.