Introduction Located in arid and semi-arid areas, the grassland of Inner Mongolia has the climatic characteristics of low precipitation, drastic climatic change and frequent disasters. In order to adapt to the extremely variable natural conditions, residents of local communities in this region have developed nomadic livestock husbandry (Aorenqi and Oerdunwuritu et al. 2009; Li 2010). Recent studies on climate changes in Inner Mongolia have observed an obvious increase in temperature levels (Gong 1995; Chen and Gong 2005; Wang et al. 2008). However, for precipitation, which is the most important factor for a grassland ecosystem, there were different conclusions. Gong (1995, 1997) found that this region’s traditional weather pattern of simultaneous rainfall and heat has changed, especially during the past 40 years where the temperature level has increased while rainfall decreased.