中文摘要：

生态系统服务价值估算旨在通过对生态系统服务价值进行评估，使生态系统评估的内容纳入国民经济核算体系，修正国内生产总值，真正促进区域的可持续发展。生态系统服务价值估算问题具有相当的复杂性和不确定性，近年来成为国内外生态学和生态经济学研究的前沿和热点。文章以石羊河流域下游民勤绿洲为主要研究范围，对民勤县1994年至2005年12年间生态系统服务的价值进行了估算和对比分析。研究结果表明，1994年区域生态系统服务的总价值为9．976×10^8元，2005年区域生态系统服务的总价值为8．475×10^8元。12年来，区域内的生态系统服务价值下降了近1．501×10^8元。由于缺乏对盐碱地、建筑用地等服务价值的相关研究信息，该结果仅是对民勤绿洲生态系统服务价值的保守估算。总的来说，研究区域生态系统服务价值呈现快速下降趋势。

英文摘要：

The evaluation of ecosystem service＇s value has some complexity and uncertainty. In recent years, the evaluation of ecosystem service＇s value has become a hot issue as well as leading study of the sustainable development research of ecological economics and ecology. Through the evaluation of the eco- system service＇s value, we bring the result into the system of national--economic accounting （SNA）, revising the gross domestic product （GDP） and accomplish the sustainable development truly. Based on the statistical data of the lower reaches of Shiyang River Basin especially Minqin Oasis from1994 to 2005, this paper estimated the ecosystem service＇s value of the Minqin County. The result shows that the annual value of the ecosystem service in the lower reaches of Shiyang River Basin was 99.76 ×108 Yuan in 1994, and 84.75× 108 Yuan in 2005. During the past 10 years, the value of the ecosystem service has been reduced by 15.01 × 108 Yuan in the region, and decreased 1. 501 ×108 Yuan per year. Due to lack of relevant data and information on the service＇s value of saline--alkali land and construction land, etc. , this result is only a conservative evaluation of ecosystem service＇s value of Minqin oasis.