Decarbonization of soil

The top metre of soils around the world contains about three times as much carbon as in our entire atmosphere. This means that soils can be a double-edged sword for tackling climate change. Land-use change and degradation, such as clearing land for farming, releases the carbon bound up in soils, adding to the CO2 accumulating in the atmosphere. On the other hand, managing soils carefully and restoring their fertility means they can take up more carbon, helping to mitigate our CO2 emissions and thereby limiting climate change.

Given the importance of soil’s carbon absorption and storage functions, the avoidance, reduction and reversal of land degradation could provide more than a third of the most cost-effective greenhouse gas mitigation activities needed by 2030 to keep global warming under the 2°C threshold targeted in the Paris Agreement on climate change, increase food and water security, and contribute to the avoidance of conflict and migration.

A major driver of the changing climate has been the release of carbon previously stored in the soil, with land degradation between 2000 and 2009 responsible for annual global emissions of up to 4.4 billion tonnes of CO2.