The impacts of globle climate changes on soil water balance, accumulated temperature, drought frequency, steppe productivity and extremes are investigated in the Songnen Steppe with model calculation results are as follows:1)According to the four GCMs model outputs, in the Songnen Steppe, temperature will rise 2.8～7.5℃ and precipitation will increase by 10% or so by the end of next century.2)With a soil water balance model, evapotranspiration and soil water content are calculated under 1×CO 2 and 2×CO 2 r...