Purpose To assess 1) the cumulative greenhouse gas emissions –GHG- and global warming potential (methane – CH 4 - and nitrous oxide) from rice fields in the growing and fallow seasons, and 2) the environmental and agronomic drivers of CH 4 emissions, and their relative capacity to explain CH 4 variation. Methods A two-year multisite field experiment covering the agronomic and environmental variability of a rice growing area in NE Iberian Peninsula was conducted with monthly samplings of GHG and monitoring of both environmental and agronomic factors. Information-theoretic framework analysis was used to assess the relative contribution of the environmental and agronomic variables on methane emissions. Results Two thirds of the CH 4 is emitted in the fallow season. Edaphic factors exert more influence during the growing season whereas agronomic factors have a higher impact in the fallow. The implications of these findings on the design of improved mitigation options rice are discussed. Conclusions Soils with higher soil sulphate concentration, bulk density and clay content emit less CH 4 in growing season. In the fallow season, the rates of both straw input and nitrogen fertilization stimulate CH 4 emissions. Graphical abstract

中文翻译：

---

甲烷排放的主要驱动因素在地中海稻田的生长和淹水休耕季节有所不同

目的 评估 1) 稻田在生长和休耕季节的累积温室气体排放量 -GHG- 和全球变暖潜能值（甲烷 - CH 4 - 和一氧化二氮），以及 2) CH 4 排放的环境和农艺驱动因素，以及它们解释 CH 4 变异的相对能力。方法 一项为期两年的多地点田间试验涵盖了伊比利亚半岛东北部水稻种植区的农艺和环境变异性，每月进行温室气体采样并监测环境和农艺因素。信息理论框架分析用于评估环境和农艺变量对甲烷排放的相对贡献。结果 三分之二的 CH 4 是在休耕季节排放的。土壤因素在生长季节的影响更大，而农艺因素在休耕期的影响更大。讨论了这些发现对设计改进的缓解方案水稻的影响。结论 土壤硫酸盐浓度、容重和粘土含量较高的土壤在生长季节排放的 CH 4 较少。在休耕季节，秸秆投入率和施氮肥均会刺激 CH 4 排放。图形概要