Lightning is a major cause of large tree mortality in a lowland neotropical forest
Lightning is a major cause of large tree mortality in a lowland neotropical forest
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DOI：
10.1111/nph.16260
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发表时间：
2019-11-18
期刊：
影响因子：
9.4
通讯作者：
Hubbell, Stephen P.
中科院分区：
文献类型：
--
作者：
Yanoviak, Stephen P.;Gora, Evan M.;Hubbell, Stephen P.
大树的死亡率对于确定热带森林的碳储量至关重要，但热带树木死亡的机制仍然知之甚少。闪电每天都会击中数以千计的热带树木，但通常认为闪电是大多数热带森林中树木死亡的次要因素。我们首次对闪电造成的死亡进行系统量化，结果表明闪电是巴拿马古老低地森林中最大树木死亡的主要原因。新型雷击定位系统结合对雷击地点的现场调查显示，平均每次雷击直接杀死 3.5 棵树（直径 > 10 厘米）并损坏 11.4 棵树。鉴于来自地球网络总闪电网络的闪电频率数据以及该地点的历史总树木死亡率，我们得出结论，闪电在短期内占大树（直径 > 60 厘米）死亡率的 40.5%，并且可能在长期内导致另外 9.0% 的大树死亡。由于气候变化而导致的云对地闪电频率的任何变化都会改变树木的死亡率；预计闪电频率增加 25-50% 将使该森林中的大树死亡率增加 9-18%。这项研究的结果表明，闪电在热带森林动态和碳循环中发挥着至关重要且先前被低估的作用。
The mortality rates of large trees are critical to determining carbon stocks in tropical forests, but the mechanisms of tropical tree mortality remain poorly understood. Lightning strikes thousands of tropical trees every day, but is commonly assumed to be a minor agent of tree mortality in most tropical forests. We use the first systematic quantification of lightning-caused mortality to show that lightning is a major cause of death for the largest trees in an old-growth lowland forest in Panama. A novel lightning strike location system together with field surveys of strike sites revealed that, on average, each strike directly kills 3.5 trees (> 10 cm diameter) and damages 11.4 more. Given lightning frequency data from the Earth Networks Total Lightning Network and historical total tree mortality rates for this site, we conclude that lightning accounts for 40.5% of the mortality of large trees (> 60 cm diameter) in the short term and probably contributes to an additional 9.0% of large tree deaths over the long term. Any changes in cloud-to-ground lightning frequency due to climatic change will alter tree mortality rates; projected 25-50% increases in lightning frequency would increase large tree mortality rates in this forest by 9-18%. The results of this study indicate that lightning plays a critical and previously underestimated role in tropical forest dynamics and carbon cycling.