ARS | Publication request: EXPLOITING HETEROGENEITY OF SOIL ORGANIC MATTER IN RANGELANDS: BENEFITS FOR CARBON SEQUESTRATION

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: August 2, 1999
Publication Date: August 1, 2001
Citation: Bird, S.B., Herrick, J.E., Wander, M.M. Exploiting heterogeneity of soil organic matter in rangelands: Benefits for carbon sequestration. Follett, R.F., Kimble J.M., Lal, R., editors. Ann Arbor Press, Chelsea, MI. The Potential of U.S. Grazing Lands to Sequester Carbon and Mitigate the Greenhouse Effect. Chapter 5. 2001. p. 121-136.

Technical Abstract: Rangelands pose unique challenges to the goal of increasing soil carbon sequestration. The high level of spatial variability associated with soil organic matter, soil aggregation, soil water, and other resources in rangelands presents unique opportunities for management. In this chapter, we review spatial heterogeneity of carbon sequestration at aggregate, plant, community, and landscape scales. We propose that Tisdall and Oades' soil aggregation hierarchy model be extended to the landscape scale, and show that this model can be applied to optimize carbon sequestration and/or rangeland function through targeted management inputs. This approach explicitly recognizes that the capacity of rangeland ecosystems to sequester carbon is a function of interactions between the spatial distribution of plant production and of soil and water resources. Management inputs can be targeted to parts of the landscape which already have a high potential for enhanced productivity and carbon storage due to higher resource availability. Although this approach can be implemented immediately, its success could be significantly enhanced by a more holistic understanding of rangeland systems and the relationships between soil structure, soil organic matter, and nutrient and water distribution at a variety of spatial scales.