Carbon limitation in trees

Summary The ongoing enrichment of the atmosphere with CO 2 raises the question of whether growth of forest trees, which represent close to 90% of the global biomass carbon, is still carbon limited at current concentrations of close to 370 p.p.m. As photosynthesis of C3 plants is not CO 2 ‐saturated at such concentrations, enhanced ‘source activity’ of leaves could stimulate ‘sink activity’ (i.e. growth) of plants, provided other resources and developmental controls permit. I explore current levels of non‐structural carbon in trees in natural forests in order to estimate the potential for a carbon‐driven stimulation of growth. The concentration of non‐structural carbohydrates (NSC) in tree tissues is considered…

• AW
  Andrew W. Mellon Foundation
• BE
  British Ecological Society
• OO
  Office of Science
• BF
  Bundesamt für Umwelt