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Titre :
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Emissions of N2O and NO associated with nitrogen fertilization in intensive agriculture, and the potential for mitigation
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Auteurs :
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K. Smith ;
I. Mac Taggart ;
H. Tsuruta
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Type de document :
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article/chapitre/communication
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Année de publication :
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1997
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Format :
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p. 296-304
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Langues:
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= Anglais
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Catégories :
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Environnement
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Mots-clés:
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FERTILISATION
;
AGRICULTURE INTENSIVE
;
AZOTE
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Résumé :
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Increases in the atmospheric concentrations of nitrous oxide (N2O) contribute to global warming and to ozone depletion in the stratosphere Nitric oxide (NO) is a cause of acid rain and tropospheric ozone. The use of N fertilizers in agriculture has direct and indirect effects an the emissions of both these gases, which are the result of microbial nitrification and denitrification in the soil, and which are controlled principally by soil water and mineral N contents, temperature and labile organic matter.The global emission of N2O from cultivated land is now estimated at 3.5 Tg N annually of which 1.5 Tg has been directly attributed ro synthetic N fertilizers, out of a total quantity applied in 1990 of about 77 Tg N. This amount was 150% above the 1970 figure. The total fertilizer-induced emissions of NO are somewhere in the range 0.5-5 Tg N. Mineral N fertilizers can also be indirect as well as direct sources of N2O and NO emissions, via deposition of volatilized NH3 on natural ecosystems and denitrification of leached nitrate in subsoils, waters and sediments.
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Source :
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Soil Use and Management, vol.13
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