Soil fertility limits carbon sequestration by forest ecosystems in a CO2-enriched atmosphere.

Published

Journal Article

Northern mid-latitude forests are a large terrestrial carbon sink. Ignoring nutrient limitations, large increases in carbon sequestration from carbon dioxide (CO2) fertilization are expected in these forests. Yet, forests are usually relegated to sites of moderate to poor fertility, where tree growth is often limited by nutrient supply, in particular nitrogen. Here we present evidence that estimates of increases in carbon sequestration of forests, which is expected to partially compensate for increasing CO2 in the atmosphere, are unduly optimistic. In two forest experiments on maturing pines exposed to elevated atmospheric CO2, the CO2-induced biomass carbon increment without added nutrients was undetectable at a nutritionally poor site, and the stimulation at a nutritionally moderate site was transient, stabilizing at a marginal gain after three years. However, a large synergistic gain from higher CO2 and nutrients was detected with nutrients added. This gain was even larger at the poor site (threefold higher than the expected additive effect) than at the moderate site (twofold higher). Thus, fertility can restrain the response of wood carbon sequestration to increased atmospheric CO2. Assessment of future carbon sequestration should consider the limitations imposed by soil fertility, as well as interactions with nitrogen deposition.

Full Text

Duke Authors

Cited Authors

  • Oren, R; Ellsworth, DS; Johnsen, KH; Phillips, N; Ewers, BE; Maier, C; Schäfer, KV; McCarthy, H; Hendrey, G; McNulty, SG; Katul, GG

Published Date

  • May 2001

Published In

Volume / Issue

  • 411 / 6836

Start / End Page

  • 469 - 472

PubMed ID

  • 11373677

Pubmed Central ID

  • 11373677

Electronic International Standard Serial Number (EISSN)

  • 1476-4687

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/35078064

Language

  • eng