草地生态系统服务功能及其价值评估方法研究

Evaluation method of ecological services function and their value for grassland ecosystems

草地不仅是畜牧业的生产基地,而且是生态安全屏障保护和牧民生活与草原文化传承的基础,具有生态、生产和生活功能。然而,草地日益退化导致的生态经济问题越来越突出,评价草地生态系统服务功能的经济价值,对于制定合理的草地保护与经济开发决策具有重要意义。目前国内外广泛采用的Costanza等提出的生态系统服务价值评估方法没能充分体现出草地生态系统本质特征。因此,本研究以草地生态系统的"三生功能"为基础,综合考虑草地的地域和空间的异质性以及区域经济发展水平的差异性,选择水源涵养、侵蚀控制、废物处理、滞留沙尘、生物多样性保护、养分循环、固定CO2、释放O2、消减SO2、畜牧生产、文化传承和休闲旅游12项贡献率较高的功能指标,应用生态经济学原理,建立了适宜于草地生态系统服务功能经济价值的评价体系和方法,并以藏北高寒草地为例,对该方法进行了评估验证。

Grasslands not only support animal production,but also play an important role as an ecological safety barrier and they maintain herders＇ livelihood as well as inherited culture.However,a series of ecological problems are becoming more and more serious because of increasing grassland degradation.The economic valuation of the grassland ecosystem service function will help conservation and rational development of grassland resources in China.Costanza＇ evaluation method for ecological services value was widely adopted abroad but this method cannot fully reflect the intrinsic characteristics of grassland ecosystems.Based on the functions of ecology,production,and living systems of grassland ecosystems,the contribution rate of the top 12 items for ecological services function of grassland ecosystems（water storage,erosion control,nutrition cycling,waste treatment,resort sand and dust,biological control,release O2,fixation CO2,cut SO2,recreation,culture,and animal production）,were chosen for this study of a comprehensive consideration of regional differences,spatial heterogeneity,and difference of economic development levels of different areas.The evaluation index system and models of grassland ecological services value were established based on the theory of ecological economics.The values of grassland ecosystem functions of the northern Tibet region were evaluated using this method.