Global warming and altered precipitation patterns pose a serious threat to crop production in the North China Plain (NCP). Quantifying the frequency of adverse climate events (e.g., frost, heat and drought) under future climates and assessing how those climatic extreme events would affect yield are important to effectively inform and make science-based adaptation options for agriculture in a changing climate. In this study, we evaluated the effects of heat and frost stress during sensitive phenological stages at four representative sites in the NCP using the APSIM-wheat model. climate data included historical and future climates, the latter being informed by projections from 22 Global Climate Models (GCMs) in the Coupled Model Inter-comparison Project phase 6 (CMIP6) for the period 2031–2060 (2050s). Our results show that current projections of future wheat yield potential in the North China Plain may be overestimated; after more accurately accounting for the effects of frost and heat stress in the model, yield projections for 2031-60 decreased from 31% to 9%. Clustering of common drought-stress seasonal patterns into key groups revealed that moderate drought stress environments are likely to be alleviated in the future, although the frequency of severe drought-stress environments would remain similar (25%) to that occurring under the current climate. We highlight the importance of mechanistically accounting for temperature stress on crop physiology, enabling more robust projections of crop yields under future the burgeoning climate crisis.

Nitrous oxide (N₂O) emissions in cereal-based rotations often show short-lived peaks after fertilization, but their contribution to annual budgets and their responsiveness to straw management remain poorly quantified. We combined a 13-year legacy fertilization experiment with two years of high-frequency N₂O monitoring in a rice–wheat rotation in central China to quantify post-fertilization peak windows and test how straw-return rate modulates these windows and annual emissions. Five long-term treatments were compared: an unfertilized control (CK), straw only (2M, 12 t ha⁻¹ yr⁻¹), mineral fertilizer (NPK), and NPK with 6 or 12 t ha⁻¹ yr⁻¹ straw (MNPK and 2MNPK). Under N input, wheat-season emissions dominated annual totals, with the ratio of wheat-season to annual N₂O emissions (WN/TN, where WN denotes wheat-season N₂O emissions and TN denotes annual cumulative N₂O emissions) of ~73–75% for NPK and MNPK, significantly higher than in CK and the straw-only control. Decomposition of annual fluxes showed that 56.6–65.4% of N₂O in N-applied treatments occurred within short windows after the two wheat-season fertilizations, whereas rice-season peaks were small and largely insensitive to treatment. Planned contrasts expressed as geometric mean ratios (GMRs) with 95% confidence intervals (CIs) highlighted a strong management leverage point: increasing straw from 6 to 12 t ha⁻¹ yr⁻¹ with NPK reduced annual and wheat-season N₂O by ~47% and 58%, respectively, primarily by lowering peak magnitude and shortening peak duration. Microbial analyses suggested that treatment effects on N₂O were better reflected by community compositional shifts (β-diversity) than by α-diversity, while amoA abundance showed guild-specific responses. Collectively, this study provides an event-window quantification framework that links high-frequency field measurements to a specific, actionable mitigation lever (straw-return rate) in rice–wheat systems. Together, these results identify wheat-season post-fertilization windows as the main control points for annual N₂O in rice–wheat rotations and show that pairing NPK fertilization with higher straw return can temper short-lived peaks. By explicitly pinpointing when (which windows) and how (attenuating peak magnitude and duration) mitigation is achieved, our findings offer a management-ready and transferable basis for targeted N₂O abatement in double-cropping systems.

Diatomite is useful in soil remediation and water purification. However, its impacts on methane (CH₄) and nitrous oxide (N₂O) emissions in paddy soils and the underlying mechanisms remain poorly understood. A pot experiment was set up with four treatments, including a non-amended control (CK), sole biochar (B), sole diatomite (D), and combined biochar–diatomite (BD) amendments, to compare their effects on CH₄ and N₂O emissions from paddy soil. Compared to CK, D and BD treatments reduced global warming potential (GWP) by 32.40% and 34.41%, respectively, significantly outperforming B treatment. All amendments reduced cumulative N₂O emissions by 50.0−62.3%, with no significant variations observed among the amended treatments. CH₄ was the primary contributor to GWP, and its emissions were most effectively reduced by diatomite. A random forest analysis found that the DOC/NO₃⁻-N ratio had a high relative influence on CH₄ emissions. B, D, and BD treatments significantly increased pmoA gene abundances by increasing redox potential and lowering the DOC/NO₃⁻-N ratio. B treatment significantly reduced mcrA gene abundances, whereas D treatment exhibited no significant effect. All amended treatments altered the methanogenic community; only D and BD affected the methanotrophic community. Overall, diatomite outcompetes biochar for reducing the GWP of rice cultivation because it more potently suppresses CH₄ emissions by improving soil aeration, favorably shifting microbial community structure and altering resource stoichiometry.

Global warming and altered precipitation patterns, which poses a serious threat to wheat pro-duction in the North China Plain (NCP). Quantifying the frequency of adverse climate events (e.g. frost, heat and drought) under future climates and assessing how those climatic extreme events would affect yield are important to effectively inform and make science-based adaptation options for agriculture in a changing climate. In this study, we evaluated the effects of heat and frost stress during sensitive period at four representative sites over the NCP using APSIM-wheat model driven by the climate projections from 22 Global Climate Models (GCMs) in the Coupled Model Inter-comparison Project phase 6 (CMIP6) during the periods of 2031–2060 (2050s). Our results showed that current projections of future wheat yield potential in the North China Plain were overestimated; after inclusion the effect of frost and heat stress in the model, the yield in-creases in potential yield under 2050s decreased from 31% to 9%. Clustering all drought-stress seasonal patterns into key groups revealed the magnitude of drought stress is projected to be al-leviated under future, but the frequency of severe drought stress yield would remain the same (25%) for the near future compared to current climate. We highlight the importance of including temperature stress effect on wheat yields under future climate change to provide more robust and reliable projected results in the NCP.