Abstract: Changes of the temperature and precipitation in Xilingol League of Inner Mongolia in the recent 51 years and the response of grassland climatic productivity to these changes were analyzed based on the meteorological data observed during the period from 1958 to 2008 using the Miami model, Thornthwaite model, Kriging interpolation and mathematical statistics method. The results revealed that the temperature increased by 2.19 ℃ in recent 51 years, its increase rate was 0.43 ℃/10 a, but precipitation decreased slightly with a decrease rate of 6.35 mm/10 a. All these revealed that climate in Xilingol League trended to be a warmingdrying pattern, and the seasonal productivity of grasslands was decreased in varying degrees. As a result, the grassland climatic productivity was inclined to decrease. There was a significant correlation between the grassland climatic productivity and the annual precipitation, and the correlation coefficient was 0.98, which suggested that water was the main factor restricting the grassland climatic productivity. The regression model is Y=169.606+7.053t+1.142r(R=0.978, P<0.01),which suggested that the annual grassland climatic productivity will be increased or decreased by 7.05 g/(m²•a) if the mean annual temperature increases or decreases by 1 ℃, and the annual grassland climatic productivity will be increased or decreased by 1.14 g/(m²•a) if the annual precipitation increases or decreases by 1 mm.

Key words: grassland climatic productivity, climate change, spatial difference, Kriging interpolation, Xilingol League, Inner Mongolia