Russian Forests, New Satellites and Computer Models: Unraveling Regional Carbon Dynamics and Feedbacks

 

Dr. Hank Shugart

 

A boreal zone forest dynamics model (FAREAST) has been developed and tested to simulate the forest cover dynamics of the Eurasian boreal forest, a major biospheric ecosystem with potentially large roles in the planetary carbon cycle and in the feedback between terrestrial surface and the atmosphere.  This region has significant potential to alter planetary CO₂ source/sink relationships (associated with growing or clearing forests) and the albedo (from changes in terrestrial surface cover).  There is some evidence that in the Eurasian Boreal zone, the Carbon budget effects from forest change may oppose the albedo changes.  This creates complex feedbacks between surface and atmosphere and motivates the need for a forest dynamics model that simultaneous represents forest vegetation and carbon storage and release.  FAREAST has been tested using three types of information:

1.      Direct species composition comparisons between simulated and observed mature forests at the same locations;

2.      Forest type comparisons between simulated and observed forests along altitudinal gradients of several different mountains;

3.      Comparison with forest stands in different succession stages of simulated forests.

Model comparisons with independent data indicate the FAREAST model is capable of representing many of the broad features of the forests of Northeastern China and the Russian Far East. 

At the same time, a fused lidar/radar satellite mission is being developed to monitor some of the structural changes predicted by models such as the FAREAST model.  The eventual implementation of this satellite system should increase out ability to monitor and, using ecological models, predict changes in the terrestrial carbon repository of the planet.