Information on forest disturbance and regrowth is essential for understanding North American carbon dynamics, and the future of the current “carbon sink”. Moderate-resolution (Landsat-type) satellite data provide the only means of constructing spatially-explicit, temporally-detailed disturbance records. This proposal seeks to continue our team’s ongoing research to generate a comprehensive record of North American disturbance and regrowth from the Landsat archive. The work relies on the use of dense (annual or biennial) time series of Landsat imagery (“data cubes”), which may be analyzed at the 30m pixel-level, using time series methodologies. Our previous work focused on obtaining a valid statistical sample of disturbance rates using 23 Landsat data cubes spread across US Forests. We also demonstrated techniques to obtain changes in aboveground live biomass associated with disturbance and regrowth by integrating Landsat reflectance trajectories with US Forest Service Forest Inventory and Analysis Program (FIA) plot-level biomass data. This proposal has six major objectives: These include: (1) Reduce error in nationwide estimates of forest disturbance and regrowth, (2) Convert data cube reflectance to data cube biomass, (3) Develop nationwide maps of forest biomass dynamics, (4) Partner with Canada and Mexico, (5) Develop formal collaborative relationships with other NACP-funded scientists, and (6) Quantify the forest component of woody encroachment nationally. Collectively, these activities will expand and refine our knowledge of North American forest dynamics, and thus significantly reduce uncertainties in carbon flux estimates:

Institutional Principal Investigators:

Chengquan Huang, Dept Geographical Sciences, University of Maryland
Warren Cohen, Pacifc Northwest Research Station, US Forest Service Covallis Oregon
Jeffery Masek, Biospheric Sciences, NASA Goddard Space Flight Center, Geenbelt, MD
Gretchen Moisen, Rocky Mountains Research Station, US Forest Service, Ogden UT

Progject Manager:  Karen Schleeweis, Dept Geographical Sciences, University of Maryland