Abstract. Although the concept of producing higher yields with reduced greenhouse gas (GHG) emissions is a goal that attracts increasing public and scientific attention, the trade-off between high yields and GHG emissions in intensive agricultural production is not well understood. Here, we hypothesize that there exists a mechanistic relationship between wheat grain yield and GHG emission, and that could be transformed into better agronomic management. A total 33 sites of on-farm experiments were investigated to evaluate the relationship between grain yield and GHG emissions using two systems (conventional practice, CP; high-yielding systems, HY) of intensive winter wheat (Triticum aestivum L.) in China. Furthermore, we discussed the potential to produce higher yields with lower GHG emissions based on a survey of 2938 farmers. Compared to the CP system, grain yield was 39% (2352 kg ha−1) higher in the HY system, while GHG emissions increased by only 10%, and GHG emission intensity was reduced by 21%. The current intensive winter wheat system with farmers' practice had a median yield and maximum GHG emission rate of 6050 kg ha−1 and 4783 kg CO2 eq ha−1, respectively; however, this system can be transformed to maintain yields while reducing GHG emissions by 26% (6077 kg ha−1, and 3555 kg CO2 eq ha−1). Further, the HY system was found to increase grain yield by 39% with a simultaneous reduction in GHG emissions by 18% (8429 kg ha−1, and 3905 kg CO2 eq ha−1, respectively). In the future, we suggest moving the trade-off relationships and calculations from grain yield and GHG emissions to new measures of productivity and environmental protection using innovative management technologies.
Effect of biochar and its combined application with manure and fertilizer on nitrogen leaching, greenhouse gas (GHG) emissions, and grain yield under alternate wetting and drying (AWD) system
