Grasslands & Agricultural Lands
Grasslands cover as much as one-third of the world’s lands, and grazing is the most extensive land use on the planet. Grasslands store fairly high levels of carbon in their soils, but a significant fraction is being lost through conversion to cropland or overgrazing. Livestock are also responsible for the majority of all non-CO2 emissions from land use.
About 10% of the earth’s land area is intensively cultivated to produce crops. Most agricultural soils have lost a large fraction of their original soil carbon, and there is considerable potential to restore this through better management. More efficient use of fertilizers can also have a large impact on global emissions of nitrous oxide, another of the six principal greenhouse gases.
In the grasslands biome, the researchers identified cropland nutrient management as offering the greatest cost-effective emissions reductions, through reduced use of fertilizers and sprays that release nitrous oxide, a greenhouse gas 300 times more potent than CO2, into the atmosphere. This would require reduction in the use of fertilizers and sprays employed by farmers worldwide, contributing a reduction of 635 million tons of carbon emissions equivalent a year by 2030, like taking 134 million cars off the road.