Athrotaxis cupressoides is an iconic Tasmanian palaeoendemic conifer that is vulnerable to fire. A survey of three populations burnt by severe fire in 2016, conducted 1 year post-fire, found 33% of stems were still alive, with many surviving stems suffering some canopy scorch. We re-surveyed these populations to quantify delayed mortality, resprouting, and presence of juveniles, and to determine whether fire impacts can be reliably assessed after 1 year. We applied three measures of fire severity: canopy scorched, canopy consumed, and the minimum burnt twig diameter of neighbouring shrubs. We found overall stem survival in 2020 was 31%, and that 97% of stems that were dead 4 years post-fire had died within the first year. Our best predictor of stem mortality was percentage canopy scorched. Overall, 1.8% of burnt stems resprouted, but severely burnt stems did not resprout. Juveniles were present ~9.9% of burnt trees in 2017, and only 1.8% in 2020. We conclude that A. cupressoides stems are not unusually fire sensitive, but rather, that the species’ vulnerability to severe fire results from its lack of reliable recovery mechanisms. This study shows that fire-caused mortality can be reliably assessed 1 year post-fire, and possibly earlier. Interventions such as sowing seed or transplanting seedlings could be necessary to re-establish fire-killed populations.

Athrotaxis cupressoides是塔斯马尼亚古老的地方性针叶树，极易着火。火灾后一年进行的一项针对2016年被大火烧毁的三个种群的调查发现，33％的茎仍然活着，许多幸存的茎遭受了冠层烧焦。我们对这些人群进行了重新调查，以量化延迟死亡，重发芽和未成年人的数量，并确定是否可以在1年后可靠地评估火灾影响。我们采用了三种火灾严重程度的度量标准：冠层烧焦，冠层消耗和相邻灌木丛的最小烧制树枝直径。我们发现，到2020年，整个茎的存活率为31％，并且在大火后4年死亡的茎中有97％在第一年内死亡。茎干死亡率的最佳预测指标是树冠灼伤百分比。总体而言，有1.8％的茎秆会发芽，但茎严重烧伤并没有萌芽。2017年，约有9.9％的树木被烧毁，而到2020年，这一比例仅为1.8％。A. cupressoides茎对火的敏感性并不高，相反，该物种对严重火的脆弱性是由于其缺乏可靠的恢复机制所致。这项研究表明，火灾后1年甚至可能更早就可以可靠地评估由火灾引起的死亡率。诸如播种种子或移栽幼苗之类的干预措施可能是重建失火人口的必要条件。