ARS | Publication request: RATE OF SOIL CARBON LOSS RESULTING FROM TILLAGE

Submitted to: International Soil Conservation Organization Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2003
Publication Date: July 4, 2004
Citation: Owens, L.B., Shipitalo, M.J. 2004. Rate of soil carbon loss resulting from tillage [abstract]. Final Program and Abstract Book of the 13th International Soil Conservation Organization Conference Abstracts. p.85.

Technical Abstract: Land management practices can have major impacts on soil carbon levels. Tillage practices cause reductions in soil carbon levels. How rapidly these reductions occur is a topic of major concern. The purpose of this study was to ascertain the rate of reduction of soil carbon with tillage over time. At the North Appalachian Experimental Watershed near Coshocton, Ohio (USA), portions of fields under multi-year no-tillage with corn (zea mays L.) or corn-soybean (zea mays L/glycine max L.) rotations have received conventional tillage. Conventional tillage includes moldboard plowing followed by disking. After the first year of conventional tillage, total carbon in the top 2.5 cm of the soil profile (3.5 Mg C/ha) was only 41 and 46% of the carbon in the top 2.5 cm of the soil profile of multi-year no-till corn (8.6 Mg C/ha) and meadow (7.7 Mg C/ha) areas, respectively. However, in the top 22.5 cm, there was no significant difference in the carbon among the three practices (35.9, 35.4, and 34.7 Mg C/ha for first year tillage, no-till, and meadow, respectively). After 13 years of consecutive conventional tillage, total carbon in the top 22.5 cm of the soil profile (30.2 Mg C/ha) was 15 and 13% less carbon than the corresponding soil depth for the no-till (35.4 Mg C/ha) and meadow (34.7 Mg C/ha), respectively. Although tillage can cause significant carbon losses over several years, the first year of tillage may not result in significant carbon loss. Other time periods of consecutive tillage are being evaluated for carbon loss with soil depth on silt loam soils to see if there is a relatively linear relationship for carbon loss with tillage over time. These additional results will be presented.