2. New World Atlas of Desertification and Issues of Carbon Sequestration, Organic Carbon Stocks, Nutrient Depletion and Implications for Food Security

Soils are both sinks and sources of C with great potential to mitigate climate change. Global estimates indicate that they contain between 1,206 Pg of soil organic carbon (SOC) to 1-m depth to more than 1,550 Pg C, which is twice the amount of C present in the atmosphere. Nevertheless the overall the C stocks could reach as much as five times that of the atmosphere considering that many soils are much deeper than 1 m. Instead, emissions from land use change are estimated to make up to 20 % of atmospheric CO₂ through loss of biomass and SOM. Notwithstanding these critical outcomes, soil’s impact in climate change scenarios is generally not well understood and the UNFCCC after CoP 21 in Paris started to increase attention to the potential for soil C sequestration thanks to the French “4 pour 1000” initiative. We argue that SLM can increase productivity particularly by improving water use efficiency, optimizing nutrient cycles and their supply for crop production, enhancing vegetation cover, and improving food security level. Healthy soils produce healthy food, support healthy living, and promote a healthy environment.