Spatiotemporal Interactions Among Biotic Disturbance Agents, Biological Legacies, and Compensatory Responses: Consequences for Temperate Forest Resilience

由于气温上升和相关的干扰，如昆虫暴发和野火，世界各地的森林正在迅速变化。北美温带针叶林面临越来越多的生物干扰(例如，昆虫和病原体暴发)，其中许多在空间和时间上同时发生，并造成未知的生态后果。这些干扰中的许多都是这些生态系统固有的，因此优势树具有共同进化的反应，导致在干扰后产生生态阻力或弹性。然而，如果生物干扰以新的方式相互作用，或者如果生物干扰后的环境条件发生变化，森林恢复的关键机制可能会发生重大变化。这项研究将评估生态系统中常见的森林恢复的生态机制；因此，结果将广泛相关，为生态复原力的理论框架提供信息，并指导科学家和管理者在生态干扰日益严重的时代。该项目将招募和指导不同的本科生，为高中课堂创建课程模块，并领导与土地管理员的外展工作。北半球温带森林广泛空间范围内的多种生物干扰因素的同步提供了一个独特的机会来测试关键假设，并向生态学理论提供关于干扰相互作用、生物遗产和补偿反应的信息。现有的永久样地森林人口学数据将与新获得的遥感产品相结合，以审查生物干扰因素之间的相互作用，以及单一和多个生物干扰后的生态系统复原力。在从树木到次大陆区域的空间尺度上，将解决两个主要研究问题：(1)在气候变暖期间，生物干扰剂之间的时空相互作用的性质是否会发生变化？(2)生物干扰留下的生物遗产的性质如何影响森林更新？野外和遥感数据将被用来建立生物干扰“热点”的模型(即两个或多个生物干扰的空间同步性)，并测试关于在生物干扰之间产生相互作用的条件的假设。多尺度数据将被用来检验关于来自干扰热点的不同生物遗产如何影响生物组织水平上的补偿反应的假设。这些多尺度数据将回答有关生物干扰和生态反应如何随着气温变暖而变化的关键问题，以及森林弹性可能被侵蚀的背景。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Forests worldwide are changing rapidly because of increasing temperatures and associated disturbances, such as insect outbreaks and wildfires. North American temperate conifer forests are facing increases in biotic disturbances (e.g., insect and pathogen outbreaks), many of which are co-occurring in space and time and with unknown ecological consequences. Many of these disturbances are native to these ecosystems, such that the dominant trees have coevolved responses that lead to ecological resistance or resilience following disturbance. However, key mechanisms of forest recovery may be altered substantially if biotic disturbances are interacting in novel ways, or if environmental conditions following biotic disturbances are shifting. This study will evaluate ecological mechanisms of forest recovery that are common across ecosystems; therefore, results will be broadly relevant for informing theoretical frameworks of ecological resilience as well as for guiding scientists and managers in an era of increasing ecological disturbances. This project will recruit and mentor diverse undergraduate students, create a curriculum module for high school classrooms, as well as lead outreach efforts with land managers.Synchrony in multiple biotic disturbance agents across broad spatial scales in temperate forests of the northern hemisphere affords a unique opportunity to test key hypotheses and inform ecological theory about disturbance interactions, biological legacies, and compensatory responses. Existing permanent-plot forest demography data will be integrated with newly acquired remote sensing products to examine interactions among biotic disturbance agents, as well as ecosystem resilience following single and multiple biotic disturbances. Across spatial scales from trees to sub-continental regions, two primary research questions will be addressed: (1) Is the nature of spatiotemporal interactions among biotic disturbance agents changing during a period of warming climate? (2) How does the nature of biological legacies left by biotic disturbances influence forest regeneration? Field and remotely sensed data will be used to build models of "hotspots" of biotic disturbances (i.e., spatial synchrony in two or more biotic disturbances), and test hypotheses about the conditions that create interactions among biotic disturbances. Multiscale data will be used to test hypotheses about how different biological legacies from disturbance hotspots affect compensatory responses across levels of biological organization. These multiscale data will answer key questions about how biotic disturbances and ecological responses are changing with warming temperatures, and contexts under which forest resilience may erode.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.