Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 6/13/2004
Publication Date: 8/24/2004
Citation: Schuman, G.E., Derner, J.D. 2004. Carbon sequestration by rangelands: management effects and potential. Proceedings of the Western Regional Cooperative Soil Survey Conference. 13-17 June, 2004, Jackson, WY, USDA, Natural Resources Conservation Service, Casper, WY. Interpretive Summary: Carbon dioxide in the atmosphere continues to rise in response to the increased use of fossil fuels. Rangelands have a great potential to sequester soil carbon and assist in the mitigation of elevated atmospheric carbon dioxide. Management strategies such as grazing, fire, fertilizer, management of woody plant encroachment and interseeding of legumes in rangelands and other grazing lands have been shown to affect soil carbon sequestration by these ecosystems. Rangelands alone have been estimated to have the potential to sequester 11 million metric tonnes of carbon annually if improved management was initiated. Grazing lands (includes improved pastures) have been estimated to have the potential to sequester 17.5 to 90.5 million metric tonnes annually depending upon management. The rate of sequestration on an area basis is smaller than for croplands or forests; however, the large land area represented by grazing lands makes these lands a very important terrestrial sink for atmospheric carbon sequestration.
Technical Abstract: Lands grazed by wild and domesticated animals comprise 336 million hectares in the United States. Rangelands account for about 48% of that land area and more than one-third of the world's terrestrial carbon reserves. Because of the large land area they have the potential to sequester a significant amount of additional carbon from the atmosphere. Grazing lands are estimated to contain 10-30% of the world's soil organic carbon. Management practices, such as grazing, nitrogen inputs, and improved plant species have been shown to increase soil organic carbon storage in rangelands. Properly managed rangelands of the United States are estimated to have the capacity to store 19 million metric tonnes of C per year. Therefore rangelands can have a major impact in mitigating the effects of elevated atmospheric carbon dioxide levels on global climate change.