Submitted to: Soil and Water Conservation Society
Publication Type: Abstract Only
Publication Acceptance Date: 8/9/1995
Publication Date: N/A
Technical Abstract: Historically, intensive tillage of agricultural soils has lead to substantial losses of soil carbon that range from 30 to 50%. While the long-term effects of tillage are reasonably clear, there are several questions that remain with respect to modifying the processes that promote carbon loss from soils. This work quantified CO2 loss from soil tilled using conservation tillage tools. Four commercially available conservation tillage tools were used to till wheat stubble cut at two different heights. Gas exchange was measured with a portable chamber immediately after tillage and followed for several hours. Results were compared to the moldboard plow and an area not tilled. Residue cover and surface roughness were measured before and after tillage for each of the conservation tillage tools and the moldboard plow. The moldboard plow caused substantially more CO2 loss than any of the four conservation tillage tools and was nearly 14 times higher than the area not tilled. Following conservation tillage tools, CO2 loss was about 4 times higher than that from the no-tilled area. The cumulative CO2 loss from the first 5 hours after tillage for the conservation tillage tools averaged only 30% of that from the moldboard plow. While conservation tillage tools are designed primarily for residue management, they have an additional beneficial effect of reducing CO2 loss. These results suggest that progress is being made in developing conservation tillage tools that can further enhance soil carbon management and support increased adoption of no-till or other forms of conservation tillage.