Applications of dendrochronology for informing terrestrial carbon cycle modeling

Abstract:

Dendrochronology provides unique ecological information on forest dynamics that can be used to develop and benchmark terrestrial carbon cycle models. In recent years, integration between dendrochronology and process-based ecosystem models has been yielded insight into climate sensitivity of tree growth, annual carbon uptake, water-use efficiency, and phenology. Here we review some of these advances as well as some of the scaling challenges associated with representing forest stand-level dynamics from individual tree growth measurements. In particular, increment cores from trees provide annual temporal resolution of biomass gain that is recorded from decade to centennial time scales. Efforts to use such measurements to reconstruct stand level biomass gain, or net primary production, have to address issues related to sampling design as well as account for mortality-driven changes in stem density that take place during stand development, what is referred to as the ‘fading record’ problem. One solution to the fading record problem is to reconstruct stem density over time by applying self-thinning theory within a calibrated forest dynamics model. With this approach, recorded tree growth and modeled stand density dynamics can be used to estimate stand-level net primary production that more accurately relates to productivity estimates from carbon cycle models. An improved understanding of trends in forest productivity over the past century is critical for a range of forest management and forest science issues, where traditional growth and yield tables exclude effects of climate and atmospheric changes in CO₂ on forest growth.