Soil Organic Carbon: Persistence, Sequestration, Vulnerability, and Stewardship
Margaret Torn (Lawrence Berkeley Laboratory)
Margaret Torn travaille au Lawrence Berkeley Laboratory.
Soils have the potential to sequester large quantities of carbon in soil organic matter. Due to the long residence times of soil organic carbon, it may be a more stable and predictable reservoir compared to sequestration in forest biomass.
However, the longterm persistence of soil organic carbon does not mean it is inert of locked up; rather it is the result of many dynamic mechanisms that can change over time. Environmental trends, like climate warming, can stimulate decomposition and accelerate loss of soil carbon to the atmosphere.
For example, our deep soil warming experiment in a California conifer forest shows large loss of subsoil (below 20 cm) carbon after five years of warming of +4°C, and other experiments have corroborating results. Thus, soil carbon sequestration requires ongoing stewardship. This presentation will share some recent insights on these aspects of soil carbon cycling.
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