中文摘要：

本文采用千年生态系统评估（Millennium Ecosystem Assessment,MA）的理论框架,结合市场价值法、影子工程法、机会成本法等方法,以土地利用变化数据、社会经济调查资料为数据源,对三江源地区1985、1996、2000、2008年生态系统服务价值进行了评估,评估的生态系统服务类型包括食物生产、调节气候、净化空气、水源涵养、控制侵蚀、废弃物降解、营养物质循环7项。结果表明：三江源地区1985、1996、2000、2008年生态系统服务总价值分别达到602.94亿元、601.58亿元、603.60亿元、669.90亿元,整体呈现先降低后增加的趋势。其中,调节气候、涵养水源的价值占据较大比例。三江源地区的生态系统服务所蕴含的巨大经济价值将对维持该地区生态平衡、保障区域可持续发展发挥重要作用。

英文摘要：

Under the framework of Millennium Ecosystem Assessment （MA）, by means of market value method, shad-ow project method, the opportunity cost method and some other methods, based on LUCC data, this paper carried out a dynamic valuation of ecosystem services in the Sanjiangyuan Region （Three-River Headwater Region）, including food production, climate regulation, gas regulation, water conservation, soil retention, nutrient regulation, and waste degradation. The results showed that： the economic value of ecosystem services in the study area was 602.94× 10^8 yu-an, 601.58 × 10^8 yuan, 603.60 × 10^8 yuan and 669.90 × 10^8 yuan in 1985, 1996, 2000 and 2008, respectively, which showed a decreasing trend at first, and an increasing one in the subsequent period. In addition, the proportion of cli-mate regulation and water conservation in the total value was high; the ecosystem services of grassland and forests played a significant part in maintaining ecosystem balance and ensuring regional sustainable development.