Weakening Climate Change and Reaching Food Security Through Soil Carbon Sequestration

There are one billion food-insecure people in the world, with the gap in cereal requirement extremely high in developing regions, and expected to triple by 2015.  Many developing countries are seeking means for reducing this gap, and sustainably increasing grain production.  Carbon Sequestration in soils has potential to mitigate climate change on a global level.  The process results in improvement of soil quality, and therefore also has positive consequences on food security and agronomic productivity.  Farmers that participate in enhancing ecosystem services will receive payments, aiding economic development in developing countries.  In his paper, Rattan Lal (2010) found the technical potential of carbon sequestration in soils to reduce atmospheric carbon dioxide by 50 ppm by the end of the 21st century, increasing the soil carbon pool (SOC) at a rate of 1 Mg/ha/year.  Food security would then be enhanced with cereal and legume production in developing countries increasing by 32 million Mg/year, and roots and tubers increasing by 9 million Mg/year.—Whitney Dawson
Lal, Rattan, 2010. Beyond Copenhagen: Mitigating Climate Change and Achieving Food Security through Soil Carbon Sequestration. Science+Business Media B.V. & International Society for Plant Pathology March, 169–77.

          Rattan Lal found that agricultural soils used by small landholders in the tropic and sub-tropic regions are significantly depleted of their soil organic carbon pool, and highly susceptible to erosion, breakdown, decline in biodiversity, and overall reduction in quality.  Crop yields are therefore very dependant on rainfall patterns, a monsoon easily resulting in crop failure, as seen in India in 2009, due to erosion and structural breakdown.  Though few experiments establishing the relationship of SOC concentration and agronomic yield have been completed, the available data show a strong relationship in areas of diverse soils, and a dramatically stronger relationship for soils of semi-arid regions, such as India.  India would see significant improvement in crop yields in a decade if SOC concentration increased by just 0.1%.  Lal includes an array of data from various studies that continue to prove the strong relationship between SOC concentration and crop yields over every type of climate across the world, including temperate regions.  The gains in agronomic production potentially achieved from increased SOC levels all depend on climate and other factors, but ultimately reduce hunger risks.
          Lal also proves SOC sequestration to be highly cost-effective overall, especially if farmers and land managers were to be compensated for their efforts in sequestering carbon in their soils.  The incentive for farmers to enhance ecosystem services and reduce carbon dioxide levels would be high, as well as the achieving of global food security.  The concept “farming carbon” would be promoted through credits of soil carbon sequestered sold to restore degraded soils, treating these credits as a farm commodity.  Lal argues that “farming carbon” could generate income that would incentivize farmers to invest in soil restoration.
There is a variety of practices that farmers are suggested to take on to enhance the SOC pools that largely involve managing a higher level of nutrients in the soil.  Lal found the optimum range of SOC concentrations in the root zone of soil to be 2–3%, a level at which agronomic yields of crops and pastures would improve if reached.  Farmers in developing countries seeking an alternative to expensive chemical fertilizers can do a number of things to reach these SOC concentration levels such as increasing water capacity, improving nutrient supplies, restoring soil structure, and minimizing soil erosion risks.  Lal concludes that these processes should have been discussed at the Copenhagen COP-15 meeting, as many were disappointed from the lack of multiple benefit strategies considered.  Restoring the SOC pool in depleted cropland soils around the world would benefit the issues of food security, climate change, and soil/environmental degradation.  

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