淅川县是南水北调中线工程渠首所在地，其区域经济发展和生态环境变化受到调水工程的影响，同时也对中线调水的水质有影响。基于1995年、2000年、2005年和2008年的土地利用/覆盖变化数据，估算了淅川县4个时期的生态系统服务价值并分析了其动态变化特征。结果表明：近20年来，淅川县生态服务价值最高为1995年的338 251×104元，由于受人类活动的影响，从1995年—2008年淅川县生态服务价值整体来讲减少了34 837×104元，其中农田和水域面积的减少是主要原因。林地、农田和水域产生的生态服务价值之和超过总价值的90%，并且水源涵养、废物处理和生物多样性保护分列生态服务功能的前三位，其价值之和接近总价值的50%。以调水工程未实施的2000年为界，淅川县生态服务价值1995年—2000年减少了73 650×104元。随着南水北调中线工程水源地生态环境建设的逐渐开展，2000年—2008年服务价值开始增加，2008年达到了303 413×104元，生态环境得到改善。2000年以来，淅川县生态服务价值与GDP的比值不断减小，也说明淅川县在生态环境保护的同时经济仍在不断发展。

Xichuan County is located at the headwork of the Middle Route of South-to-North Water Diversion Project, thus its regional economic development and ecological environmental change are affected by the project, and it can also affect the water quality of the project. In this paper, based on the land use/cover maps of year 1995, 2000, 2005, and 2008, the ecosystem service values and their dynamic variation characteristics of Xichuan County were calculated and analyzed for the four years. The results indicated that the highest ecosystem service value of Xichuan County was 3382.51 million RMB in 1995. Due to the effects of human activities, the ecosystem service value of Xichuan County had lost 348.37 million RMB from 1995 to 2008, and the decreasing of cultivated land and water body was the main reason. The ecosystem service values of woodland, cultivated land, and water body accounted for 90% of the total value. The water conservation, waste treatment, and bio-diversity protection were the top three ecological functions and their ecosystem service values accounted for 50% of the total value. The ecosystem service value of Xichuan County lost 736.50 million RMB from 1995 to 2000. With the gradual implementation of the ecological environment construction of the Middle Route of South-to-North Water Diversion Project, the ecosystem service value of Xichuan County began to increase from 2000 and 2008 and reached 3034.13 million RMB in 2008. Moreover, the ratio of ecosystem service value to GDP has decreased since 2000, which indicated the existence of ecological environment protection and economic development in Xichuan County.

国家自然科学基金项目“基于NDVI的流域产流产沙对LUCC响应的快速预测及尺度效应”（50979003）