Soil carbon sequestration

Soil carbon sequestration results from land management practices aiming to increase the soil organic carbon content, resulting in a net removal of carbon dioxide (CO₂) from the atmosphere.

In NSW agricultural land considerable potential exists for soil organic carbon sequestration, for example in pasture land in the higher rainfall regions (>450 mm), for both as permanent pastures or as ley pasture in the cropping zone. Considerable increases can be achieved by pasture improvement and improved management practices.

Soil organic carbon levels in ecosystems are controlled by a range of factors, namely climate, soil, vegetation and time and can reach an equilibrium level under specific environmental conditions (environmental equilibrium). Over time, change in the storage of soil organic carbon is controlled by the balance between carbon inputs and losses (removal through mineralisation to carbon dioxide, and erosion). The difference in soil organic carbon between the environmental equilibrium levels and the current depleted level is the soil organic carbon sequestration potential, that is, the potential carbon sink, because theoretically this quantity can be restored to the soil.

More information on soil carbon sequestration potential can be found here

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