| Registro completo |
| Provedor de dados: |
Organic Eprints
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| País: |
Germany
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| Título: |
Long-term effects of cropping system on N2O emission potential
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| Autores: |
Petersen, Søren O.
Ambus, Per
Elsgaard, Lars
Schjønning, P.
Olesen, Jørgen E.
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| Data: |
2013
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| Ano: |
2013
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| Palavras-chave: |
Soil biology
Air and water emissions
Farm nutrient management
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| Resumo: |
The potential for N2O emissions outside the main growing season may be influenced by long-term effects of cropping system. This was investigated by collecting intact soil cores (100 cm3, 0-4 cm depth) under winter wheat in three organic cropping systems and a conventional reference within a long-term crop rotation experiment. Average annual inputs of C in crop residues and manure ranged from 1.7 to 3.3 Mg ha-1. A simulated freeze-thaw cycle resulted in a flush of CO2 during the first 48 h, which could be mainly from microbial sources. Other samples were adjusted to approximately –10, -30 or –100 hPa and amended with excess 15NO3- prior to freezing and thawing. Denitrification was the main source of N2O during a 72-h incubation at 22C, as judged from N2O and total 15N evolution. Although the input of C in the conventionally managed cropping system was significantly less than in the organic cropping systems, it showed higher N2O evolution at all three matric potentials. Estimates of relative gas diffusivity (DP/D0) in soil from the four cropping systems indicated that C input affected soil aeration. Soil from the two cropping systems with highest C input showed N2O evolution at DP/D0 in excess of 0.02, which is normally considered a threshold for development of anaerobic sites in the soil, presumably because the oxygen demand was also high. The study shows that cropping system affects both soil gas diffusivity and C availability, and that both characteristics significantly influence the N2O emission potential.
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| Tipo: |
Journal paper
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| Identificador: |
http://orgprints.org/22014/1/22014.pdf
Petersen, Søren O.; Ambus, Per; Elsgaard, Lars; Schjønning, P. and Olesen, Jørgen E. (2013) Long-term effects of cropping system on N2O emission potential. Soil Biology and Biochemistry, 57, pp. 706-712.
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| Relação: |
http://orgprints.org/22014/
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| Formato: |
application/pdf
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