Disturbance suppresses the aboveground carbon sink in North American boreal forests
Disturbance suppresses the aboveground carbon sink in North American boreal forests
复制标题
干扰抑制了北美北方森林的地上碳汇
DOI：
10.1038/s41558-021-01027-4
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发表时间：
2021
影响因子：
30.7
通讯作者：
M. Friedl
中科院分区：
文献类型：
--
作者：
Jonathan A. Wang;A. Baccini;M. Farina;J. Randerson;M. Friedl
气候变化正在改变北方生态系统中的植被和干扰动态。然而，这些变化对北方碳预算的总体影响还没有得到很好的理解。在这里，我们结合了多个卫星数据集来估计北美北部北部地区的年储量和地上生物量(AGB)的变化。从1984年到2014年，2.82 × 106 Km2研究区获得了AGB的434 ± 176 Tg。火灾造成的损失为789 ± 48 Tg，大部分由火灾后恢复的642 ± 86 Tg弥补。木材采伐造成74 ± 5 Tg的损失，但采伐后恢复的32 ± 9 Tg部分抵消了这一损失。地球系统模型高估了AGB累积量3倍(+1,519 ± 171 Tg)，这表明这些模型高估了北方生态系统中的陆地碳汇，并强调了需要改进这些模型中对火和其他干扰过程的描述。在未来的气候变化下，火灾、干旱、收获和昆虫等干扰机制可能会加剧。尽管部分抵消了再生的影响，但火灾和收获的干扰减少了北方森林的碳吸收和储存，影响了这种碳汇的强度。
Climate change is altering vegetation and disturbance dynamics in boreal ecosystems. However, the aggregate impact of these changes on boreal carbon budgets is not well understood. Here we combined multiple satellite datasets to estimate annual stocks and changes in aboveground biomass (AGB) across boreal northwestern North America. From 1984 to 2014, the 2.82 × 10 6 km 2 study region gained 434 ± 176 Tg of AGB. Fires resulted in losses of 789 ± 48 Tg, which were mostly compensated by post-fire recovery of 642 ± 86 Tg. Timber harvests contributed to losses of 74 ± 5 Tg, which were partly offset by post-harvest recovery of 32 ± 9 Tg. Earth system models overestimated AGB accumulation by a factor of 3 (+1,519 ± 171 Tg), which suggests that these models overestimate the terrestrial carbon sink in boreal ecosystems and highlights the need to improve representation of fire and other disturbance processes in these models. Disturbance regimes from fire, drought, harvest and insects will probably intensify in the future and under climate change. Despite partial offsets from regrowth, disturbance from fire and harvest reduces carbon uptake and storage in boreal forests, impacting the strength of this carbon sink.
影响因子：
64.8
作者：
Walker, Xanthe J.;Baltzer, Jennifer L.;Mack, Michelle C.
通讯作者：
Mack, Michelle C.