Soil takes its fill of carbon
The ability of soil to store carbon will weaken as carbon dioxide levels in the atmosphere rise to the amounts predicted for the end of this century, suggests a report in Nature this week.
Richard A. Gill of Duke University, Durham, North Carolina, and colleagues present evidence from field experiments on a grassland ecosystem. They show that soil's traditional role as a carbon sink could now be at an important threshold.
Soils may have played a role in taking up carbon dioxide since the last ice age, but their ability to continue to do so may be limited by nutrient availability, warn the researchers.
Source: Nature 417, 279 (2002)
Link to paper by Richard A. Gill et al
Photo credit: David J. Moorhead, The University of Georgia, Image 0005012. ForestryImages.org.http://www.forestryimages.org/. May 16, 2002.