LTER: Cross-scale controls over responses of the Alaskan boreal forest to changing disturbance regimes

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Alaska has warmed more than twice as rapidly as the rest of the United States over the past century, with some of the largest increases occurring in boreal (pine) forests far from the coast. This warming has triggered large changes in the number and size of wildfires, the melting of frozen soil, patterns of water flow, and outbreaks of insects and diseases. Thus, Alaskan landscapes are changing rapidly in complex ways, which is important because the changes directly affect the availability of natural resources and ecosystem services to Alaskan residents. More generally, changes to landscapes in the far North are of global significance because boreal forests cover vast areas and play a role in determining the Earth's climate. Understanding how and why boreal forests respond as they do to a warmer world is important for predicting both regional and global changes over the next century. This Long Term Ecological Research (LTER) project, started in 1987, will continue to provide long-term data on how changing climate impacts Alaskan forests and the people who depend on them for a living. This LTER research will test new ideas and gain fresh insights of the type possible only from studies that last decades. The LTER scientists will also continue their long history of collaboration with state and federal agencies regarding forest and wildlife management, especially in regard to increasing disturbance from fire. This project represents an integrated research program to study the cross-scale controls over responses of the Alaskan boreal forest to changing climate-disturbance interactions, including the associated consequences for regional feedbacks to the climate system, and to identify vulnerabilities and potential adaptations to social-ecological change with rural Alaskan communities and land management agencies. The project addresses the dynamics of change through the integration of five components: 1) Studying direct effects of climate change on ecosystems and disturbance regimes by characterizing controls over the spatial heterogeneity of ecosystems and disturbances, and the sensitivities of these controls to regional climate, and by studying the spatial and temporal synchrony of multiple disturbances to assess which landscapes are most vulnerable to change; 2) Understanding patterns, mechanisms, and consequences for scale-dependent climate-disturbance interactions involving current and legacy influences of fire, permafrost, and trophic dynamics as drivers of ecosystem and landscape change; 3) Linking landscape heterogeneity with regional and global climate feedbacks by studying and modeling how intermediate-scale patterns and processes influence regional scale ecosystem dynamics and climate feedbacks; 4) Studying how climate variability and change are affecting coupled social-ecological dynamics by characterizing variability in changes to ecosystem services across a select group of interior Alaskan communities, and collaborating with communities to find solutions that reduce vulnerability and improve adaptation to social-ecological change; 5) Integrating science and resource management with regional environmental change by coordinating research activities with agencies to fill management knowledge gaps, assessing outcomes of policy decisions, and communicating syntheses to policy makers in meaningful ways.