Mapping Stand Ages of Primary Forests in Northern Hemisphere Using Remote Sensing Data

Gong Zhang, NASA ARC BAERI, zhanggong07@gmail.com
Weile Wang, CSUMB&NASA/ARC, weile.wang@gmail.com (Presenter)
Ensheng Weng, Princeton, weng@princeton.edu
Sangram Ganguly, NASA ARC BAERI, sangramganguly@gmail.com
Sassan Saatchi, CALTECH/JPL, sasan.s.saatchi@jpl.nasa.gov
Ramakrishna R. Nemani, NASA ARC, rama.nemani@nasa.gov

The age distribution of forest stands records the history of disturbances occurred to the ecosystem and is critical in evaluating the status of the forest carbon cycle. Traditionally, mapping the forest stand ages at large scales represents a challenge because the spatial heterogeneity across different landscapes prevents reliable interpolations from point-based measurements. Here we propose a new method to address this problem by utilizing spatially continuous and consistent satellite datasets of forest biomass and net primary production (NPP). This method is derived from basic equations of forest carbon dynamics with simplified statistical characteristics of the disturbance regime. We applied the algorithm to generate a first satellite-based map of stand ages for the primary forests over the entire Northern Hemisphere. The results indicate a distinct east-to-west transition of forest ages from 70 to above 200 years across North America, which is consistent with previous ground-based estimates. The map also identifies less variability in forest stand ages, ranging between 100 to 150 years, over Eurasia. The uncertainty associated with the estimated forest stand ages is generally ±10-20% except for certain regions in Siberia. Therefore, the developed method provides a cost-effective way to regularly mapping stand ages of natural forests at regional-to-global scales.

Presentation Type:  Poster

Session:  Carbon Monitoring System (CMS) Posters   (Mon 1:30 PM)

Associated Project(s): 

• Cook, Bruce: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Griffith, Peter: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Hall, Forrest: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Leidner, Allison: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Masek, Jeff: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Nemani, Rama: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Saatchi, Sassan: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details
• Tucker, Compton: NASA CMS Pilot Projects: Biomass and Carbon Storage ...details

Poster Location ID: 175