1. Short-term effect of tillage intensity on NO and CO emissions.
- Author
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Boeckx, Pascal, Van Nieuland, Katja, and Van Cleemput, Oswald
- Subjects
TILLAGE ,CARBON offsetting ,GREENHOUSE gas mitigation ,NITROUS oxide & the environment ,FARM management - Abstract
The effect of tillage on the overall greenhouse gas balance of croplands is not clear. It has been suggested that ceasing tillage increases C sequestration, but has the risk of enhancing NO emission, which could switch the greenhouse gas balance from negative to positive. We studied the short-term effect of tillage intensity on NO and CO emissions. We changed reduced tillage to conventional tillage or no tillage and performed two tillage operations in two growing seasons. All other parameters such as agricultural management, climate, and crop type at the study site, an intermediately aerated Luvisol in Belgium, were similar. Nitrous oxide and CO emissions were measured event-directed about 40 times per year from September 2006 until December 2008 using a closed chamber technique. We did not observe any significant short-term effect of tillage intensity on NO emissions during the 2 years following tillage conversion. The 2-year aggregated NO emission was not affected by the absence of tillage, 5.6 kg NO-N ha, compared to conventional tillage, 4.6 ± 0.9 kg NO-N ha, or reduced tillage, 4.7 ± 0.3 kg NO-N ha. Enhanced NO emission events in the absence of tillage, 1 year after conversion, could be explained by the combination of higher N application and wetter conditions. Conversion to conventional tillage caused a small, but significant, increase in CO emission over the same period. We conclude that in the short term, none of the tillage intensities had an effect on NO emission, and the effect on CO emission was slightly positive when tillage intensity increased. A low short-term risk of increased NO emission in the absence of tillage in well-aerated croplands is beneficial agro-environmentally, but the long-term effect should also be assessed via follow-up studies. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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