Résumé
This review is an assessment of technologies and management options that distinguishes between (i) practices and (ii) classes, e.g., the practice of Alternate Wetting and Drying (AWD) falls under the class water management for mitigation benefits in rice systems. At the level of practices, the results are presented through directional indicators comparing the intervention against a defined control practice in terms of GHG emissions and grain yields. The tabulated indicators provide a multifaceted picture of each intervention practice that quantify how consistent different interventions were across studies on mitigation impact. While a few practices showed a clear reduction for an individual GHG across studies, other practices were represented by two-directional indicators even for the same category with upward and downward indicators for both methane and nitrous oxide. This ambiguity in impact was then reflected at the level of intervention class, which was analyzed in terms of the average and range of relative impacts as well as the number of publications assessed. Except for water management, which showed a clear mitigation impact on methane emissions, the other intervention classes covered a broad range of impacts from a reduction to an increase in GHG emissions. Finally, we provide descriptive (non-quantitative) assessments of newly proposed mitigation options that are still at the conceptual stage. The conceivable interventions are comprehensively presented to guide GHG mitigation by focusing on methane reduction to identify additional research for the development of novel technologies, and to guide policy-makers to maximize the benefits of each proven intervention.