What was done
The authors reviewed the published literature to gain a better understanding of how photosynthetic acclimation to elevated CO2 is manifest at the whole-plant level.

What was learned
Over long periods of time, photosynthetic and growth responses to elevated CO2 are dependent upon a plant's ability to develop sinks for utilizing additional carbon acquired from enhanced rates of photosynthesis.  However, the formation and maintenance of additional sinks can only be supported if adequate amounts of nitrogen are available to a plant.  Fortunately, growth in air of elevated CO2 concentration often results in a reallocation of nitrogen away from foliar photosynthetic enzymes and into developing sinks within the plant.  This phenomenon often results in a significant increase in the photosynthetic nitrogen-use efficiency of a CO2-enriched plant and aids in the stimulation of biomass production.

What it means
As the CO2 content of the air rises, it is likely that many plants will respond by exhibiting some degree of acclimation to this phenomenon, including the mobilization of nitrogen away from the photosynthetic apparatus to other developing sinks to support increased biomass production.