Worldwide maize and soybean yield response to environmental and management factors over the 20th and 21st centuries

Global yield for maize increases under RCP4.5-SSP2, which experiences continued growth in [CO2] and higher nitrogen input rates. For soybean, yield increases at a similar rate. However, in RCP8.5-SSP5, maize yield declines because of greater climate warming, extreme heat stress conditions, and weaker nitrogen fertilization than RCP4.5-SSP2, particularly in tropical and subtropical regions, suggesting that application of advanced technologies, and stronger management practices, in addition to climate change mitigation, may be needed to intensify crop production over this century.

The model also projects spatial variations in yields; notably, the higher temperatures in tropical and subtropical regions limit photosynthesis rates and reduce light interception, resulting in lower yields, particularly for soybean under RCP8.5-SSP5.