Legume-based rotation benefits crop productivity and agricultural sustainability in the North China Plain

Abstract

Diversified rotation through legume inclusion supports sustainable crop production and reduces environmental risks, representing a key strategy for sustainable agriculture. However, the impacts of legume-based rotation on cropping system productivity and carbon (C) emissions have not been thoroughly investigated. Here, a field experiment was conducted to examine the impacts of three cropping systems (peanut-wheat, soybean-wheat vs. maize-wheat rotation) and two fertilization treatments (with and without fertilization) on crop yield, C footprint (CF), and agricultural sustainability. Our findings revealed that legume inclusion resulted in a higher crop yield (+40 % on average) than maize-wheat, and the yield advantage was 80% higher without than with fertilization. This demonstrated the effectiveness of legumes in enhancing crop production under low-input conditions. Legume inclusion enhanced the annual net income by 2.8 times over maize-wheat under no fertilization, while income declined by 20 % under fertilization. Notably, compared to maize-wheat, the direct greenhouse gas (GHG) emissions under legume-wheat decreased by 43 %, while indirect GHG emissions showed no significant difference. Furthermore, legume inclusion mitigated soil C stock loss by 1579 (kg C ha⁻¹ yr⁻¹) under no fertilization and increased soil C stock by 3766 (kg C ha⁻¹ yr⁻¹) under fertilization, further reducing the CF (-31 %) and enhancing the agricultural sustainability (+86 %). In conclusion, our study indicates that legume-based rotation represents a vital strategy for promoting sustainable crop production and environmental advantages, particularly within low-input agricultural systems.