Nitrogen cycling drives a strong within-soil CO(2)-sink

作者：Fleischer Siegfried^*; Bouse Ivo

来源：TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY, 2008, 60(5): 782-786.

DOI：10.1111/j.1600-0889.2008.00374.x

For about three decades, it has not been possible to completely balance global carbon emissions into known pools. A residual (or 'missing') sink remains. Here evidence is presented that part of soil respiration is allocated into an internal soil CO(2)-sink localized to the saprophytic subsystem (roots excluded). The process occurs in forest, agricultural and grassland soils and is favoured by high N-deposition. Chemoautotrophic nitrification has a key role, and the most efficient internal CO(2)-sequestration occurs concurrently with lowest soil nitrate (NO(3)(-)) concentrations, despite considerable N-loading. Not until drastic N-supply occurs, does the CO(2)-sink successively breakdown, and nitrate concentrations increase, leading to NO(3)(-)-leaching. Within-soil CO(2)-uptake seems to be of the same magnitude as the missing carbon sink. It may be gradually enforced by the ongoing input of nitrogen to the biosphere.

• 出版日期2008-11