Collaborative Research: The biology of lightning in tropical forests

闪电是一种异常强大的自然现象；纵观历史，它的破坏性影响一直是人类恐惧和迷恋的根源。科学家们对闪电的物理特性有了相对较好的理解，但它在景观尺度上的生态重要性——尤其是它作为树木死亡媒介的作用——仍然不清楚。测量热带森林中闪电的影响很重要，因为随着气候变暖，预计未来几十年闪电频率将增加50%。此外，随着藤本植物（木本藤本植物）的丰富，热带森林结构正在发生变化。这项研究将为理解这些变化如何影响巴拿马热带雨林的森林动态和生态系统过程（如碳循环）提供基础。巴拿马的场地是一个受欢迎的旅游目的地，因此该项目为参与者提供了一个与公众定期互动的独特机会。学生培训是该项目的一个组成部分。与肯塔基科学中心的合作将产生一个播客，突出这项研究，并以科学咖啡馆的形式与项目参与者进行公开讨论。生态学家一直将闪电列为热带树木死亡的原因之一，但支持这一观点的数据非常缺乏。该项目将系统地量化闪电对热带树木和藤本植物在整个森林范围内的实时影响。这项工作将整合来自野外生态学、物理学和植物电生理学的信息，以回答三个基本问题：在低地热带森林景观中，闪电导致树木死亡的程度有多大？是否有些树木或树种特别容易受到或抵抗闪电的破坏性影响？藤本植物是否起到避雷针的作用，保护它们的宿主树木免受雷击的伤害？实地工作将在巴拿马进行，这是世界上研究得最好的热带森林地点之一。该方法包括安装自动电子传感器，用于监测大面积森林冠层上的打击事件。该项目还将部署一个实验性闪电感应装置——气球引发闪电触发器——以实验性地操纵对孤立岛屿上树木和藤本植物的打击事件。这项工作的结果将从根本上改变我们对热带森林动态的理解，通过量化闪电对整个景观的影响，并揭示闪电、藤本植物和树木之间的关键相互作用。在实际情况下，该项目还将揭示通信塔和树冠起重机对树木死亡率的潜在混淆影响。本提案由环境生物学部和物理学部的生命系统物理项目共同资助。

Lightning is an exceptionally powerful natural phenomenon; its destructive effects have been a source of fear and fascination for humans throughout history. Scientists have a relatively good understanding of the physics of lightning, but its ecological importance at the landscape scale - especially its role as an agent of tree death - remain unclear. Measuring the effects of lightning in tropical forests is important because lightning frequency is expected to increase by as much as 50% over the next few decades as the climate warms. Moreover, tropical forest structure is changing as lianas (woody vines) become more abundant. This research will provide the foundation for understanding how such changes will affect forest dynamics and ecosystem processes such as carbon cycling in the tropical rainforests of Panama. The field site in Panama is a popular tourist destination, thus the project provides a unique opportunity for participants to interact regularly with the public. Student training is an integral part of the project. Collaboration with the Kentucky Science Center will result in the production of a Podcast highlighting this research, and public discussions with project participants in a Science Café format. Ecologists consistently list lightning as a source of tropical tree mortality, yet supporting data are remarkably scant. This project will systematically quantify lightning effects on tropical trees and lianas on a forest-wide scale in real time. The work will integrate information from field ecology, physics, and plant electrophysiology to answer three basic questions: What is the extent of lightning-caused tree mortality across a lowland tropical forest landscape? Are some trees or tree species especially susceptible to, or resistant to, the damaging effects of lightning? Do lianas function as lightning rods, protecting their host trees against lightning damage? Field work will be conducted in Panama at one of the best-studied tropical forest sites in the world. The methodology includes the installation of automated electronic sensors for monitoring strike events over large expanses of forest canopy. This project will also deploy an experimental lightning induction device - the Balloon Originating Lightning Trigger - to experimentally manipulate strike events to trees and lianas on isolated islands. Results of this work will fundamentally transform our understanding of tropical forest dynamics by quantifying lightning effects across the landscape and uncovering key interactions between lightning, lianas, and trees. In a practical context, this project will also reveal potentially confounding effects of communications towers and canopy cranes on tree mortality rates. This proposal is co-funded by the Division of Environmental Biology and the Physics of Living Systems program in the Physics Division.