How strong was the anthropogenic imprint in the disturbance regime of eastern Canadian mixed forests during the 20th century? And how did it alter the tree species composition? To answer these questions, we reconstructed the 20th century anthropogenic disturbance regime and analyzed its impact on modern forest composition using historical and modern forest inventory and map data. Between 1895 and 2005, an equivalent of 144% of the study area has been logged and 19% burned. The logging rotation period has shortened from 152 years in 1895–1935 to 47 years in 1965–2005, due to increased industrial capacity. The fire rotation period decreased from 1668 years in 1895–1925 to 200 years during the peak of human settlement (1925–1955), and then increased to 2925 years in 1955–2005. The geographical progression of anthropogenic disturbances in the landscape has reflected the socio-economic context. During the 20th century, logging moved inland from the margins of the main water courses, reflecting the shift in wood transport from log driving on rivers to the densification of the road network in the second half of the 20th century. Most fires were located at low altitude, close to private lands suggesting ignitions from anthropogenic origins. Fire prone species (poplars) are mostly found within burned areas. Despite these disturbances, forest composition remained relatively stable, suggesting resilience of regional forest ecosystems.

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20 世纪加拿大东部混交林中不断变化的干扰机制

20 世纪加拿大东部混交林的干扰机制中的人为印记有多强？它是如何改变树种组成的？为了回答这些问题，我们重建了 20 世纪的人为干扰机制，并使用历史和现代森林清单和地图数据分析了其对现代森林构成的影响。1895 年至 2005 年间，相当于研究区 144% 的面积已被砍伐，19% 的面积已被烧毁。由于工业产能增加，测井轮转周期从1895-1935年的152年缩短到1965-2005年的47年。火灾自转周期从1895-1925年的1668年减少到人类定居高峰期（1925-1955年）的200年，然后在1955-2005年增加到2925年。景观中人为干扰的地理进展反映了社会经济背景。在 20 世纪，伐木业从主要水道边缘向内陆转移，反映了木材运输从河流上的原木运输到 20 世纪下半叶道路网络的密集化转变。大多数火灾发生在低海拔，靠近私人土地，这表明起火是人为的。容易着火的物种（杨树）大多出现在燃烧区域。尽管受到这些干扰，森林组成仍然相对稳定，表明区域森林生态系统具有恢复能力。反映了 20 世纪下半叶木材运输从河流原木运输到道路网络密集化的转变。大多数火灾发生在低海拔，靠近私人土地，这表明起火是人为的。容易着火的物种（杨树）大多出现在被烧毁的地区。尽管受到这些干扰，森林组成仍然相对稳定，表明区域森林生态系统具有恢复能力。反映了 20 世纪下半叶木材运输从河流原木运输到道路网络密集化的转变。大多数火灾发生在低海拔，靠近私人土地，这表明起火是人为的。容易着火的物种（杨树）大多出现在被烧毁的地区。尽管受到这些干扰，森林组成仍然相对稳定，表明区域森林生态系统具有恢复能力。