The likely impact of rising atmospheric CO2 on natural and managed Populus: a literature review

Because of their prominent role in global biomass productivity, as well as their complex structure and function, forests and tree species deserve part icular attention in studies on the likely impact of elevated atmospheric CO 2 on terrestrial vegetation. Poplar (Populus) has proven to be an interesti ng study object due to its fast response to a changing environment, and the growing importance of managed forests in the carbon balance. Results of bo th chamber and field experiments with different poplar species and hybrids are reviewed in this contribution. Despite the variability between experime nts and species, and the remaining uncertainty over the long term, poplar i s likely to profit from a rising atmospheric CO2 concentration with a mean biomass stimulation of 33%. Environmental conditions and pollutants (e.g. O -3) may counteract this stimulation but with managed plantations, environme ntal constraints might not occur. The predicted responses of poplar to risi ng atmospheric CO2 have implications for future forest management and the e xpected forest carbon Sequestration. (C) 2001 Elsevier Science Ltd. All rig hts reserved.