南湖新闻网讯（通讯员 李晓云）近日，我校粮食安全数智治理实验室、经济管理学院李晓云教授团队在农业经济学领域期刊Agricultural Economics上发表了题为“Climate change-induced northward shifts in double cropping system in China: Implications for crop production potential and water use”的研究成果。

在气候变化重塑农业生产格局的背景下，作物种植结构调整已成为农业生产系统适应气候变化、保障粮食安全的重要途径。该研究基于长时间序列的农业与气候数据，整合了1965—2019年气象站点逐日气候观测数据与1985—2019年县级农业生产统计数据。在明确不同区域种植制度、作物生育期及其适宜水热条件的基础上，研究识别了长期气候变化对中国北方地区不同粮食作物种植比例的异质性影响，评估了气候变化驱动的作物种植结构调整对粮食产量的增产效应。通过进一步将作物生产力、复种指数以及社会经济因素纳入分析框架，为从主动性适应视角引导种植结构调整以提升粮食安全保障能力提供了经验证据。

研究结果表明，不同粮食作物对长期气候变化的响应存在显著差异。玉米生育期有效积温（GDD）每增加10 °C·day，玉米种植比例提高约0.24%；而有效积温对小麦播种面积占比则具有抑制作用。上述影响在寒冷地区和一年一熟制区域更为明显，反映出气候变化影响在不同气候禀赋和种植制度背景下具有显著空间异质性。同时，降水增加显著促进了小麦和玉米种植比例的提升，其中对小麦的促进效应更为突出。进一步测算得出，研究期内气候变化驱动的种植结构调整累计推动中国粮食总产量增加约1.42%。机制分析表明，有效积温上升增强了春玉米相对于春小麦的生产优势，推动了玉米面积的扩张；降水增加则主要通过促进复种指数提升影响作物种植结构。此外，灌溉水平和产粮大县属性能够有效调节气候变化对作物种植比例的影响，凸显了基础设施与生产能力在农业适应气候变化中的关键作用。

我校经济管理学院博士生刘楚杰为文章第一作者，李晓云教授为通讯作者。合作作者包括国际玉米小麦改良中心（CIMMYT）的Jordan Chamberlin教授与国际食物政策研究所高级研究员、华中农业大学宏观农业研究院游良志教授。该研究得到了教育部哲学社会科学研究重大课题攻关项目、国家社科基金重大项目、国家自然科学基金的共同支持。

英文摘要：Climate change may shift double cropping system into new areas and increase cropping intensity in some regions, creating opportunities to boost crop production. However, these changes also reshape the land-water-food nexus, particularly by increasing irrigation demand and exacerbating tensions between crop production and water scarcity. In this study, we integrated multi-dimensional datasets during 1980-2019 to identify the traditional and potential expansion areas of double cropping system and empirically analyze how cropping intensity responds to climate change. We further assessed the resulting impacts on crop production and water use, and explored feasible strategies for promoting double cropping. Results reveal the potential northward expansion of the double cropping system driven by climate warming, covering 6.72 x 106 hm2 of cropland. The multiple cropping index in traditional double cropping areas exhibited a pronounced response to climate warming, whereas potential expansion areas showed a weak and insignificant response. In the latter, the mean multiple cropping index was 0.99 during 2014-2019, indicating considerable untapped potential for more efficient use of climate and land resources. Using the winter wheat-summer maize system as a representative double cropping pattern, we found its expansion during the study period increased crop production by 39.18 Mt and irrigation demand by 15.17 x 109 m3 in traditional double cropping areas, where the agricultural water resources stress index reached 3.47 in 2019. In potential expansion areas, under two hypothetical scenarios & horbar;converting spring maize to winter wheat-summer maize and fully utilizing idle arable land for the same rotation & horbar;national grain production could potentially increase by 2.16% and 0.88%, respectively, with irrigation demand rising by 10.85 x 109 m3 and 4.52 x 109 m3. The agricultural water stress index would rise to 2.04 and 1.87 under the two scenarios, yet compared with traditional double cropping areas, water pressure in these regions would remain manageable. The study highlights the importance of fully leveraging emerging climatic resources to boost crop production in double cropping regions as a climate adaptation strategy. It also provides a comprehensive assessment of the trade-offs between increased food production and water use, offering valuable insights for promoting sustainable agricultural development in double cropping regions.

论文链接：https://doi.org/10.1111/agec.70093

审核人：李谷成