Optimizing crop rotation and irrigation strategy increases soil carbon and reduces GHG emissions without sacrificing yields
Yang, Y and Ti, J and Zou, J and Wu, Y and Rees, RM and Harrison, MT and Li, W and Huang, W and Hu, S and Liu, K and Wen, X and Chen, F and Yin, X, Optimizing crop rotation and irrigation strategy increases soil carbon and reduces GHG emissions without sacrificing yields, Agriculture, Ecosystems and Environment pp. 1-37. ISSN 0167-8809 (In Press) [Refereed Article]
Enhancing soil organic carbon (SOC) while concurrently reducing greenhouse gas (GHG) emissions and without compromising yield is a contemporary challenge for many agricultural sectors across the globe. In China, resolving this apparent contradiction is prioritized in the policy targets required to deliver "Peak Carbon" and "Carbon Neutrality". The present study explores the potential to increase SOC stock while reducing GHGs emissions, without sacrificing crop yields by optimizing crop rotations and irrigation using a 6-year experiment in the North China Plain (NCP). Our results show that crop yields were higher in the irrigated treatments compared with the rainfed treatments. Yield was highest in the winter wheat-summer maize (WM), followed by the winter wheat-summer soybean (WS) and the winter wheat-summer maize-spring maize (WMMs). SOC stock in the surface soil layer (0-20 cm) increased in the irrigated treatments but the rate of SOC stock in the rainfed treatments decreased over time for all rotations. SOC stock of WMMs was greatest of all treatments, leading to the highest carbon sustainability index (CSI) for this treatment. N2O emissions were 23-57% higher in the irrigated treatments compared with the rainfed treatments for the three rotations, which was highest in WMMs and lowest in WS. Carbon footprints (CFs) were highest in WS and lowest in WMMs. Moreover, increasing SOC is beneficial for reducing CFs and increasing yield. WMMs under irrigated treatment were most effective at increasing SOC stock and reducing GHG emissions with relatively high yield in this study, suggesting this treatment would make a significant contribution to agricultural green development in the NCP and other regions in the world that similar to the NCP .
greenhouse gas emissions, carbon capture, storage, soil carbon, net zero, carbon neutral, land use change, climate change, extreme climatic events, vegetation, trees, forestry, rotation, biodiversity, carbon neutral ecosystems services, net-zero