It has been suggested that conversion to organic farming contributes to soil carbon sequestration, but until now a comprehensive quantitative assessment has been lacking. Therefore, datasets from 74 studies from pairwise comparisons of organic vs. nonorganic farming systems were subjected to metaanalysis to identify differences in soil organic carbon.

Much work has been done since 1992 to move the world closer to a common and sustainable future, but 20 years down the road we have yet to deliver on this fundamental principle – too many people in this world are still not living a healthy and productive life while the world grows in ways that are not always in harmony with nature. FAO seeks to stimulate consensus on the changes needed at, global, regional and national levels to eradicate hunger, support the transition to sustainable food consumption and production systems and ensure greater fairness in food management. It calls for this consensus to be translated into a deep and sustainable commitment to act. And it appeals to all stakeholders represented at Rio+20 to adopt with urgency a new resolve to work together in a genuine spirit of cooperation and partnership to implement the steps needed and hold themselves accountable for achieving the first principle of Rio 1992.