Wildfires cause critical shifts in ecosystem functions, such as dramatic reductions in vegetation productivity. However, how fast vegetation regains its pre-fire productivity levels and the key influencing factors remain poorly understood on a global scale. Here we present the global estimates of post-fire vegetation productivity recovery from 2004 to 2021 using gross primary productivity observations and related proxies at a spatial resolution of 10 km, employing a random forest model to identify the key factors influencing recovery time. Roughly 87% of burned vegetation regained pre-fire productivity levels within 2 years, with evergreen needleleaf forests and savannas displaying the lengthiest recovery periods. During the recovery phase, post-fire climate conditions, such as soil moisture, vapour pressure deficit and air temperature, had nonlinear impacts on recovery time globally. These climatic factors exhibited a dominant role in regional recovery time in ~89% of the globally assessed area. As climate aridity decreased, the areas where recovery time was dominated by soil moisture and vapour pressure deficit decreased, while the influence of temperature increased. Soil-moisture-dominated regions witnessed reduced proportions of promoting vegetation recovery as aridity decreased, whereas vapour pressure deficit and air-temperature-dominated regions saw an increase in such proportions. Regions with strong human interventions were associated with accelerated vegetation recovery compared with similar ecosystems with smaller human interventions. These findings had important implications for global carbon-cycle assessments and fire-management strategies.

野火导致生态系统功能发生重大变化，例如植被生产力急剧下降。然而，全球范围内植被恢复火灾前生产力水平的速度以及关键影响因素仍然知之甚少。在这里，我们使用空间分辨率为 10 公里的总初级生产力观测值和相关代理，提出了 2004 年至 2021 年火灾后植被生产力恢复的全球估计，并采用随机森林模型来确定影响恢复时间的关键因素。大约 87% 的烧毁植被在两年内恢复到火灾前的生产力水平，其中常绿针叶林和稀树草原的恢复期最长。在恢复阶段，火灾后的气候条件，如土壤湿度、蒸气压不足和气温，对全球恢复时间产生非线性影响。这些气候因素在全球评估区域约 89% 的区域恢复时间中发挥了主导作用。随着气候干旱程度的降低，恢复时间以土壤水分和水汽压亏缺为主的地区减少，而温度的影响增加。随着干旱的减少，以土壤水分为主的地区促进植被恢复的比例减少，而水汽压亏缺和气温主导的地区则促进植被恢复的比例增加。与人类干预较小的类似生态系统相比，人类干预较强的地区植被恢复加速。这些发现对全球碳循环评估和火灾管理战略具有重要意义。