Abstract: Based on meteorological data from 105 stations in Inner Mongolia,three elements of Holdridge life zone classification system,annual precipitation,annual biotemperature and potential evapotranspiration ratio,were calculated,and the threshold of three elements of Inner Mongolia grassland types were determined.On that basis,the general climate index(GCI) of Inner Mongolia grassland was constructed,and the quantitative climatic distribution indicators of Inner Mongolia grassland types were determined.Inner Mongolia grassland types were divided according to the climatic distribution indicators,which was consistent with the actual types of Inner Mongolia grassland.The climatic distribution indicators could reflect the spatial distribution conditions of Inner Mongolia grassland types,and could apply to Inner Mongolia grassland climatic regionalization.

Key words: Holdridge life zone, Holdridge life zone, Grassland types, Climatic distribution indicators, Inner Mongolia