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The distribution of grasslands is determined by climatic conditions,but climate has changed under the background of constant warming.Climate trends in Qinghai were analyzed based on data from fifty meteorological stations from 1961 to 2007.The analysis was divided into two periods:pre and post 1987.Differences in temperature and precipitation pre and post 1987 were significant.The rate of temperature increase was 0.16℃/10a before 1987 and 0.64℃/10a after 1987.The change in precipitation was 0.14 mm/10a before 1987 and 3.92 mm/10a after 1987.The grassland distribution was determined according to the Comprehensive and Sequential Classification system.Thirteen grassland types were identified from 1961 to 1987,and eleven types from 1988 to 2007.The tendency of types based on data from 1988 to 2007 compared with types based on data from 1961 to 1987 was wanning and drying.Under a doubling of CO2 concentrations,temperatures were higher,but there was no obvious increase in precipitation.Grassland was divided into nine types,and the tendency was towards warming and drying.This analysis showed that the number of grassland types has decreased in response to climatic wanning and drying.