Usins an approach to link crop simulation model and climate change scenarios, the effects of global climate change on soybean, yield and irrigation requirement in the Northeast China Plain, the North China Plain and the Middle and Lower Valley of the Yangtze River were evaluated. Besteds, chanses in the northern limit for summer - sowing soybean, moisture condititon and soybean quanlity were analyzed, interms of several successful agroclimatic indices and mathematical methods. The direct effedts of CO2 on s...