Smouldering wildfire is an important disturbance to peatlands worldwide; it contributes significantly to global carbon emissions and provides positive feedback to climate change. Herein, we explore the feasibility of firebreaks to control smouldering peat fires through laboratory-scale experiments. The dry-mass moisture content (MC) of peat soil was varied from 10% (air-dried) to 125%. We found that smouldering peat fire may be successfully extinguished above the mineral soil layer, even if the peat layer is not entirely removed. There are two criteria for an effective peat firebreak: (I) adding water to make the peat layer sufficiently wet (>115% MC in the present work); and (II) ensuring that the peat layer is thinner than the quenching thickness (< 5 cm). Criterion I may fail if the water table declines or the peat layer is dried by surface fires and hot weather; thus, satisfying Criterion II is more attainable. A sloping trench-shaped firebreak is recommended to guide water flow and help maintain high peat moisture content. This work provides a scientific foundation for fighting and mitigating smouldering wildfires and provides guidance about protective measures for field-scale peat fire experiments.

闷燃的野火是对全世界泥炭地的重要干扰。它为全球碳排放做出了重要贡献，并为气候变化提供了积极的反馈。本文中，我们通过实验室规模的实验探索了防火区控制闷烧泥炭火灾的可行性。泥炭土的干重水分含量（MC）从10％（风干）变化到125％。我们发现，即使没有完全清除泥炭层，闷烧的泥炭火也可以成功地扑灭在矿物土壤层上方。有效的泥炭防火有两个标准：（I）添加水以使泥炭层充分湿润（当前工作中MC> 115％）；（II）确保泥炭层薄于淬火厚度（<5厘米）。如果地下水位下降或泥炭层由于地面起火和炎热天气而变干，则标准I可能会失败。因此，更符合条件II。建议使用倾斜的沟槽状防火带来引导水流并帮助维持较高的泥炭水分含量。这项工作为扑灭和减轻闷烧的野火提供了科学依据，并为野外规模的泥炭火灾实验提供了保护措施。