Abstract: C value is a parameter of the water-heat correlative equation proposed by Qiwu Cui (1981), which characterizes the dryness or wetness of a region. Based on the  observation data from 150 weather stations in Inner Mongolia in 1961-1990, this paper calculated the mean annual C value and >5 °C accumulated temperature (AT5) over the 30-year period in this region, and spatially interpolated them into raster grids with 8 km resolution by Kriging. In combining with the map of vegetation regionalization, a scatter plot map of C value and AT5 for ten vegetation zones in Inner Mongolia was produced, which better reflected the relationships between the vegetation zones and climatic indices in Inner Mongolia. The ranges ofC value and AT5 for each vegetation zone were determined. According to the determined C value and AT5, the spatial distribution of the vegetation zones in Inner Mongolia was simulated. Kappa test showed that C value combined with AT5 could better reflect the spatial distribution of vegetation zones in Inner Mongolia. As a comprehensive climatic index, C value could provide important information for simulating the distribution of vegetation zones in Inner Mongolia.

Key words: development mechanism, sustainable livelihoods, non-agricultural index, participatory rural appraisal, concentrated poverty area.