John E. Drake

Institute for Genomic Biology
Room 1500
1206 W. Gregory Drive
Urbana, IL 61801 (MC 195)
(217) 333-1632
johndrake@life.uiuc.edu

CV

I am a forest ecophysiologist studying how individual tree physiology and ecosystem level processes interact, and how this interaction is altered by changes in the environment associated with global change. I am involved in two projects for my Ph.D research.

(1) I am one of many scientists that use the Duke Free Air CO2 Enrichment (FACE) site in an attempt to understand ecosystem-level responses to elevated atmospheric carbon dioxide concentrations. I have published a manuscript on fine root respiration at this site, and I am working on a synthesis on how the belowground cycling of C and N is affected by 12 years of CO2 enrichment.

(2) All of the ecosystem level CO2 enrichment in forests has been performed in relatively young plantations, and it is unclear if the response of young forests will be maintained as these forests age and undergo successional change in community composition. As it is very unlikely that the Duke FACE experiment will run for >100 years, I initiated a forest chronosequence study using 12 forests near the FACE site that vary in age from 14 to 115 years old. The general approach of this project is to understand the mechanisms driving age-related changes to production and C cycling in the absence of CO2 enrichment, and to use this information to predict how the Duke FACE results will apply in old forests. I have quantified primary productivity across the chronosequence, and identified progressive hydraulic limitation of photosynthesis as a driver of a decline in production with increasing age using a variety of techniques, including measurements of gas exchange, sap flow, and stable isotopes. I am now attempting to code these mechanisms into the Ecosystem Demography model to predict the effect of global climate change on young forests undergoing secondary succession over long time scales.