Impacts of future climate change and management practices to yield, eco-efficiency and global warming potential for rice-wheat rotation system.

Background: The rice-wheat rotation system (RWRS) is a predominant cropping pattern in mid-eastern China, playing a crucial role in ensuring food security. However, its intensive water and fertilizer inputs contribute significantly to greenhouse gas (GHG) emissions. With global climate warming, RWRS confronts the dual imperative of simultaneously enhancing productivity and eco-efficiency while significantly curtailing GHG emissions.

Results: Future warming climate under most global climate models (GCMs) had adverse impacts on yield, water-use efficiency (WUE), nitrogen-use efficiency (NUE) and GHG intensity (GHGI) of RWRS in the central and southern regions of mid-eastern China. Compared to traditional management (TM) with high water and nitrogen inputs, optimized water and nitrogen management (OM) - utilizing intermittent irrigation and a nitrogen application rate of 390 kg ha^-1 - can significantly enhance WUE and NUE while reducing GHGI, without compromising yield. Moreover, no tillage, as a conservation tillage (CT) practice could effectively mitigate the negative impacts of future climate change. The combination of OM and CT (OM + CT) can improve yield and eco-efficiency while reducing global warming potential. For RWRS with OM + CT, GHGI decreased by 45.6-60.9% under future climate scenarios compared to TM.

Conclusions: By using knowledge-based optimum management strategies, environmental risks can be reduced without sacrificing the yield of RWRS yield. This study demonstrates a useful approach with crop modelling to ensure yield for agriculture system at a lower environment cost, which can be adjusted and applied in other farming systems and regions. © 2025 Society of Chemical Industry.