Although there are many theories that explain how forests function at the stand level, there is a lack of understanding of how these theories scale to larger areas subject to different disturbances, such as hurricanes or harvests, which cause temporary change in environmental conditions. Management of forest resources has been guided by ecological theories that simplify disturbance, management, and climate impacts on forests, but feedbacks from management are seldom considered to influence function. This observation leads to an important question: How does knowledge from studies of areas measured in meters or kilometers apply to much more heterogeneous regional areas, within which human activities are becoming the most significant determinants of functional responses to disturbances? This proposed research aims to develop a framework for building forest management into Earth system modeling to test whether stand-level ecological theories hold in larger areas across different regions of the continental US. The goal is to determine how variations in forest management, climate, and disturbance impact forest ecosystems, and quantify the relative importance of forest management, climate, and disturbance as drivers of ecosystem structure and function at stand to continental scales. Initial spatial data on land ownership and use, forest management, disturbances, climate, and vegetation characteristics will be obtained for two regions of the US with significant management activity: the Southeast and Pacific Northwest. The project will map management, disturbances, and environmental characteristics overlain on forest types. An ecosystem model will be modified and parameterized to generate estimates of carbon, water, and forest structure characteristics under various management and climate scenarios in order to investigate if the macrosystem behaves similarly or as the aggregate of the mosaic of different stages of succession, management, disturbance, and climate change scenarios.
This continental-scale analysis of management, disturbance, and climatic effects on forest structure and function will lead ecologists and forest resource managers towards improved stewardship of forest resources. This project will make substantive contributions in developing methods for appropriate scale determination and management mapping, and demonstrate how management methods affect forest ecology. Moreover, new frameworks and improvements will be made to improve existing ecosystem models. This project will improve ecological theory of succession to better inform forest management, which will help in evaluating forest feedbacks on climatic patterns. Research data products will made available to forest managers via outreach activities, including field-based workshops. The greatest significance of this project will be to design new research approaches and contribute to training a new generation of scientists through graduate research and cross-disciplinary post-doctoral training with multi-institution lab rotations. The project will improve our understanding of the interactions of forest management at larger scales with disturbance regimes and climate change influences, as well as how management activities might mitigate some of those influences.
