Author
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Owens, Lloyd |
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Submitted to: American Forage and Grassland Council Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 10/19/2007 Publication Date: 1/26/2008 Citation: Owens, L.B. 2008. Soil carbon levels in pastures in the humid United States under different fertility levels [abstract]. American Forage and Grassland Council Conference Proceedings, January 26-31, 2008, Louisville, Kentucky. 2008 CD-ROM. Interpretive Summary: Technical Abstract: With current global climate change concerns, there is increased interest in the role of agriculture in CO2 release or sequestration. Tillage based practices tend to release soil carbon while non-tillage practices and forage crops tend to sequester carbon. There is a need for greater quantification of soil carbon levels with different land uses such as forages/pastures. At the North Appalachian Experimental Watershed research station near Coshocton, OH, different beef pasture management systems have been studied for over 30 years for soil and water quality impacts. These systems include a non-rotational system with no fertilizer inputs (unimproved); a weekly rotational system with annual mineral N fertilizer inputs ranging from 56 kg ha-1 to 168 kg ha-1 (medium fertility); and a weekly rotational grazing system with annual N fertilizer inputs of 224 kg ha-1 to grass and a grass-legume mixture without N fertilizer (high fertility). There was a steady increase in soil C in the unimproved grazing system from 1975 through 2006, but it was still below the soil C levels measured in the medium and high fertility systems. Soil C levels in both the medium and high fertility systems were similar and showed no particular trends over the 30 years of study (ranging from 21 to 26 g kg-1 soil in the 0-15 cm layer). Soil C levels in multi-year, no-till corn/soybean-rye rotation were below 20 g kg-1 soil. |
