The global ecology of forests

Abstract

t is shown that research on the forest carbon balance performed in the last two decades has allowed: the identification of forest ecosystems, including primary forests, as important carbon sinks; the assessment of ecosystem respiration as the main determinant of ecosystem carbon balance; the evaluation of the interannual variability of carbon exchange and its regulation by environmental conditions; the assessment of the vulnerability of some ecosystem components, like soils, that could release to the atmosphere part of the huge amount of carbon that has accumulated over millennia. It is shown, on the other hand, that several aspects of ecosystem functioning and the interaction between global change components (for instance, the relationship between carbon and nitrogen cycles) call for a better interpretation, and that general circulation models do not represent in a satisfactory way several processes that could be important in determining the exchange of matter and energy between the biosphere and the atmosphere. For these reasons the future role of forests and the biosphere in the
mitigation of greenhouse effect and climate change is still an open question.