Exploration of feasible rice-based crop rotation systems to coordinate productivity, resource use efficiency and carbon footprint in central China

Resource scarcity, large environmental footprint and low economic profits are great challenges faced by global crop production. Development of feasible cropping systems that can coordinate productivity and sustainability is critical for addressing these challenges. Here, field experiments were conducted from 2017 to 2020 to compare the energy equivalent yield, energy use efficiency, labor and water productivity, carbon footprint, and net ecosystem economic benefits of the six rice-based crop rotation systems in central China, including rice-wheat (RW), rice-rapeseed (RRs), double-season rice (DR), ratoon rice (RR), maize-rice (MR), and rice-fallow sys-tems (RF). The results demonstrated that MR had the highest energy equivalent yield of 20.3 Mg ha-1 among all the tested rotation systems, which was significantly increased by 28.0%, 32.8%, 18.9%, 26.9%, and 99.5% compared with that of RW, RRs, DR, RR, and RF, respectively. MR and RR achieved higher energy use efficiency than RW, RRs and DR due to their higher total energy output and lower total energy input, respectively. Meanwhile, MR and RR also exhibited the highest water and labor productivity among these rotation systems, respectively. Furthermore, their carbon footprint per area and per energy output were comparable to those of RW and RRs, but significantly lower than those of DR. Overall, MR and RR increased the net ecosystem economic benefits by 12.6???76.8% and 25.1???188.3% relative to other four traditional systems (RRs, RW, DR and RF), respectively. These results suggest that MR and RR are the recommended feasible rice-based crop rotation sys-tems to coordinate high productivity, resource use efficiency, and economic benefit with lower carbon footprint in central China.

Automated summary

Resource scarcity, large environmental footprint, and low economic profits are major challenges for global crop production. Field experiments comparing six rice-based crop rotation systems in central China showed that the maize-rice and rice-fallow systems had higher productivity, resource use efficiency, and economic benefits with lower carbon footprint.