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

University Of Washington, Seattle WA

Investigators

Abstract

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.