Collaborative Proposal: Redefining the ecological memory of disturbance over multiple temporal and spatial scales in forest ecosystems

点击翻译按钮获取中文摘要

Most research on forests occurs within a single forest or only over a few years or, less often, a few decades. It is typically believed that local disturbances affect trees only in that forest. However, recent evidence suggests that disturbances affected forests over hundreds of miles and more by the same series of drought events and a hard spring frost that occurred 250 years ago. These extreme weather events made it possible for many ancient trees within this region to grow from small saplings into the canopy trees they are now. These large-scale but very short-lived events like drought and frost are predicted to occur more often and become worse in the future. If that happens, regional forest declines could become more important in the future. To see if this is a real possibility, this award will yield new data from old forests throughout the Northeastern U.S. to investigate how trees and forests respond to extreme events similar to those from 250 years ago. The broader impacts will focus on recruiting people who are not well represented in scientific and academic institutions. Students and project participants will be trained on how to conduct science with humility, have respect for all people, and to combat institutional racism and gender bias. The team will be active on social media and make presentations at scientific meetings, public lectures, and educational events to share what is learned through our study.The ecological memory of forested ecosystems to extreme climatic events is not adequately captured by theories of disturbance and vegetation models; the common scale of ecological research is spatially too small and temporally too short to capture long-term ecosystem development. This award will investigate multiple data streams with two dynamic vegetation models and Bayes hierarchical modelling to answer several questions, including: 1) How do extreme climatic events impact ecosystem development and ecological processes? and 2) What are the long-term interactions between local, high-frequency disturbance (windstorms, gap dynamics, etc.) and large-scale, low-frequency disturbance (severe drought)? Through these questions, the research will rigorously test theory by confronting models with realistic disturbance scenarios from 600 years of tree-growth data covering 400,000 km2 of the northeastern US to determine to what extent extreme climatic events synchronize disturbance across spatial scales and their potential long-term legacies. The award outcomes will be useful in forecasting climate-forest interactions, as extreme events are expected to increase in the future. By scaling from seasons to centuries, this project bridges short- and long-term studies to provide information at the scales necessary to guide land use decisions in complex systems under a changing climate. In addition to training, the project will conduct a modelling workshop to push the margins of forest science by inviting experts and people from a range of disciplines and underrepresented groups to produce a conceptual paper at the intersection of data-model assimilation, Bayesian statistics, and spatial and temporal analyses.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.