Experimental confirmation of ecosystem model predictions comparing transient and equilibrium plant responses to elevated atmospheric CO2

Ecosystem models predict that short-term responses to elevated atmospheric CO₂ may differ substantially from the "real" long-term responses expected at equilibrium. Experimental validation of these model predictions is difficult as the data available are from short-term studies that do not include biogeochemical feedbacks typical of long-term exposure. Using a reciprocal transplant design at a natural CO₂ spring, we generated combinations of atmospheric and soil conditions that represented both short- and long-term elevated CO₂ conditions. Plant responses were significantly different between these treatments, confirming model predictions that there is not a simple relationship between transient and equilibrium responses to elevated CO₂.