Disturbances such as wildfires are an integral part of forest ecosystems, but climate change is increasing their extent, frequency, intensity and severity, compromising forest ecosystem services (ES) that are fundamental to human well-being. Thus, evaluating the risk of losing ecosystem services due to wildfires is essential for anticipating and adapting to future conditions. Here, we analyze the spatial patterns of the risk of losing key forest ES and biodiversity (that is, carbon sink, bird richness, hydrological control and erosion control) due to wildfires in Catalonia (NE Spain), taking into account exposed values, hazard magnitude, susceptibility and lack of adaptive capacity. We also determine the effect of climate and different forest functional types on the risk of losing ES under average and extreme hazard conditions (defined as median and 90th percentile values of the Fire Weather Index, respectively), as well as on the increase in risk. Our results show that hazard magnitude is the most important component defining risk under average conditions. Under extreme conditions, exposed values (carbon sink capacity and erosion control) emerged as the most important components of risk. Climate was the main driver of ES at risk under average conditions, but the high vulnerability of non-Mediterranean conifer forests with a low adaptive capacity gained importance under extreme conditions. The increase in risk between average and extreme conditions was driven by precipitation, as the highest increases in risk were found in relatively wet forests with low average risk at present. These results have direct implications on the future risk of losing ES to wildfires in Mediterranean forests but also in other regions, and they could contribute to future policies by anticipating conditions associated with particularly high risk that can be used to guide efficient forest management.

野火等干扰是森林生态系统不可或缺的一部分，但气候变化正在加剧其范围，频率，强度和严重性，损害了对人类福祉至关重要的森林生态系统服务（ES）。因此，评估因森林大火而丧失生态系统服务的风险对于预测和适应未来情况至关重要。在这里，我们分析了加泰罗尼亚（西班牙北部）因野火造成的主要森林生态系统和生物多样性丧失风险的空间格局（即碳汇，鸟类致富，水文控制和侵蚀控制），并考虑了暴露的价值，危害幅度，易感性和缺乏适应能力。我们还确定了气候和不同森林功能类型对在平均和极端危害条件下（分别定义为“火灾天气指数”的中位数和第90个百分数值）造成的ES丧失风险的影响，以及对风险增加的影响。我们的结果表明，危害程度是定义平均条件下风险的最重要组成部分。在极端条件下，暴露的价值（碳汇能力和侵蚀控制）成为风险的最重要组成部分。在一般条件下，气候是ES面临风险的主要驱动力，但适应能力差的非地中海针叶林的高度脆弱性在极端条件下变得尤为重要。平均和极端条件之间的风险增加是由降水驱动的，因为目前在相对较低的平均风险较低的相对潮湿的森林中，风险增加最高。这些结果直接影响着地中海森林以及其他地区因森林大火而失去生态系统的未来风险，并且它们可以通过预见与特别高的风险相关的条件来为将来的政策做出贡献，这些风险可以用来指导有效的森林管理。