Abstract:In order to predict and evaluate the ecological service values under different land use types in Yanchi County,Ningxia Hui Autonomous Region,a research on the changes of land uses and ecological service values was conducted for six types of land uses(farmland,forestland,grassland,saline land,desert and other lands).Results showed that from 1999to 2004,the amount of transferred grassland and farmland was greater than other land uses,with farmland being mainly transferred to grassland.From 2004to 2010,the transferred farmland and grassland were still more than other land uses,and the conversion between grassland and farmland still occurred in this period,with a small portion of grassland being turned into desert.In these years,the total ecological service value of 2004was the highest and the overall trend first increased and then decreased.In the first class service,the values for regulating services and support services were greater than others,but the annual changes were insignificant.Soil conservation,biodiversity conservation and climate regulation dominated in the second class service.Generally,the contribution from forestland and grassland was the largest in these years.