Future implications of climate change on maize yield and quality in the Yellow River Basin of China

Climate variability, including global warming, spatiotemporal changes in precipitation, etc., has implications for the growth and development of cereal crops, posing a concealed threat to future food security. The Yellow River Basin (YRB) holds significant importance in China's agricultural landscape, serving as a vital hub for the cultivation of maize and the production of grains. This study employed meteorological grid data simulated by the Climate-Weather Research and Forecasting model (CWRF), in conjunction with the Decision Support System for Agrotechnology Transfer (DSSAT) model, to forecast the prospective ramifications of climate change on maize phenology, yield, and grain nitrogen content (GNC) within the YRB from 2020 to 2050. Our results indicated that the YRB is expected to experience increasing trends in temperature, radiation, and precipitation from 2020 to 2050. Significant spatial variations were observed across the YRB in maize phenology, yield, and GNC. The overall growth period of maize in the entire basin is projected to be reduced by 13 days, comprising a 5-day decrease from sowing to flowering and an 8-day decrease from flowering to maturity. The future maize yield in the YRB exhibits a general declining pattern, with an average reduction of 10.5%, and the decline in yield is more pronounced in the Eastern region compared to the Western region. In forthcoming years, there will be an estimated average increase of 5.6% in maize GNC within the YRB, characterized by higher GNC levels observed in the middle and eastern parts of the basin while witnessing a decrease in GNC for maize cultivation specifically within its western regions. With time, the changes in maize indexes of phenology, yield, and quality would intensify in the future. Under the premise of unchanged field management measures in the future, there would be certain mutual inverse constraints between maize yield and GNC in YRB. In other words, an increase in maize yield would lead to a decrease in maize GNC, and vice versa. Hence, implementing appropriate modifications to irrigation and fertilizer regimes could offer a viable approach for enhancing both the yield and quality of maize in the area.