Rocky Mountain forests are poised to recover following bark beetle outbreaks, but with altered composition

Amplified by warming temperatures and drought, recent outbreaks of native bark beetles (Curculionidae: Scolytinae) have caused extensive tree mortality throughout Europe and North America. Despite their ubiquitous nature and important effects on ecosystems, forest recovery following such disturbances is poorly understood, particularly across regions with varying abiotic conditions and outbreak effects. To better understand post-outbreak recovery across a topographically complex region, we synthesized data from 16 field studies spanning subalpine forests in the Southern Rocky Mountains, USA. From 1997 to 2019, these forests were heavily affected by outbreaks of three native bark beetle species (Dendroctonus ponderosae, Dendroctonus rufipennis, and Dryocoetes confusus). We compared pre- and post-outbreak forest conditions and developed region-wide predictive maps of post-outbreak (1) live basal areas, (2) juvenile densities, and (3) height growth rates for the most abundant tree species ...升温与干旱加剧了本土小蠹虫（象甲科：小蠹亚科，Curculionidae: Scolytinae）的近年暴发，在欧洲与北美范围内造成了大面积树木死亡。尽管此类虫害分布广泛且对生态系统影响重大，但人们对这类扰动后的森林恢复机制仍知之甚少，尤其是在非生物条件与虫害暴发影响各不相同的区域。为更好地理解地形复杂区域的虫害暴发后森林恢复情况，我们整合了美国南落基山脉亚高山森林的16项野外研究数据。1997年至2019年间，这些森林深受三种本土小蠹虫物种（山松大小蠹Dendroctonus ponderosae、云杉大小蠹Dendroctonus rufipennis、暗异小蠹Dryocoetes confusus）暴发的严重影响。我们对比了虫害暴发前后的森林状况，并针对区域内优势树种绘制了暴发后三项指标的全域预测图谱：(1) 活立木断面积、(2) 幼树密度、(3) 树高生长速率……