Healthy soils provide the largest store of terrestrial carbon

Healthy soils play an important role in climate change mitigation by storing carbon (carbon sequestration) and decreasing global greenhouse gas emissions in the atmosphere. However, if soils are managed poorly or cultivated through unsustainable agricultural practices, soil carbon can be released into the atmosphere in the form of carbon dioxide (CO₂), which can contribute to climate change. Our soils are under increasing pressure and the steady conversion of grassland and forestland to cropland and grazing lands over the past several centuries has resulted in historic losses of soil carbon worldwide. 

By restoring degraded soils and adopting soil conservation practices, there is major potential to decrease the emission of greenhouse gases from agriculture, enhance carbon sequestration and build resilience to climate change.

SOILS AND THE CARBON CYCLE

The carbon cycle is the exchange of carbon (in various forms, e.g., carbon dioxide) between the atmosphere, ocean, terrestrial biosphere and geological deposits. Most of the carbon dioxide in the atmosphere comes from biological reactions that take place in the soil. Carbon sequestration occurs when carbon from the atmosphere is absorbed and stored in the soil.  

THE THREAT OF CLIMATE CHANGE: WHAT CAN BE DONE?

Climate change represents a serious threat to global food security, not least because of its effects on soils, particularly in the most vulnerable and food-insecure countries that are less resilient to irregular weather phenomenon. Changes in temperature and rainfall patterns can have a great impact on the organic matter and processes that take place in our soils, this can greatly increase the risk of crop failure and loss of livestock.

WHAT IS CLIMATE SMART AGRICULTURE AND HOW DOES IT WORK?

Climate smart agriculture (CSA) is a unified approach promoted by FAO to develop the technical, policy and investment conditions that support its member countries in achieving food security under climate change. CSA practices sustainably increase productivity and resilience to climate change (adaptation), while reducing and removing greenhouse gases whenever possible (mitigation).

As part of its two pilot projects in Tanzania and Kenya, FAO’s Mitigation of Climate Change in Agriculture (MICCA) programme selected and promoted the uptake of different practices based on experts and participatory assessments with farmers. Some 9 000 farmers in both countries, 40 percent of whom were women, received training on climate-smart agriculture, resulting in 736 energy-efficient cooking stoves being adopted to reduce deforestation. 79 tree nurseries were created, 417 000 tree seedlings were planted and 6 ha of terraces were established (on 204 farms) to conserve soil and water. Two biogas digesters were also installed to produce renewable energy from cow manure.