Spatially explicit estimates of N2 O emissions from croplands suggest climate mitigation opportunities from improved fertilizer management
© 2016 John Wiley & Sons Ltd.
Veröffentlicht in: | Global change biology. - 1999. - 22(2016), 10 vom: 17. Okt., Seite 3383-94 |
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Weitere Verfasser: | , , , , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2016
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Zugriff auf das übergeordnete Werk: | Global change biology |
Schlagworte: | Journal Article N2O climate change emissions flooded rice greenhouse gas manure meta-analysis nitrogen nitrous oxide mehr... |
Zusammenfassung: | © 2016 John Wiley & Sons Ltd. With increasing nitrogen (N) application to croplands required to support growing food demand, mitigating N2 O emissions from agricultural soils is a global challenge. National greenhouse gas emissions accounting typically estimates N2 O emissions at the country scale by aggregating all crops, under the assumption that N2 O emissions are linearly related to N application. However, field studies and meta-analyses indicate a nonlinear relationship, in which N2 O emissions are relatively greater at higher N application rates. Here, we apply a super-linear emissions response model to crop-specific, spatially explicit synthetic N fertilizer and manure N inputs to provide subnational accounting of global N2 O emissions from croplands. We estimate 0.66 Tg of N2 O-N direct global emissions circa 2000, with 50% of emissions concentrated in 13% of harvested area. Compared to estimates from the IPCC Tier 1 linear model, our updated N2 O emissions range from 20% to 40% lower throughout sub-Saharan Africa and Eastern Europe, to >120% greater in some Western European countries. At low N application rates, the weak nonlinear response of N2 O emissions suggests that relatively large increases in N fertilizer application would generate relatively small increases in N2 O emissions. As aggregated fertilizer data generate underestimation bias in nonlinear models, high-resolution N application data are critical to support accurate N2 O emissions estimates |
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Beschreibung: | Date Completed 23.08.2017 Date Revised 02.12.2018 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1365-2486 |
DOI: | 10.1111/gcb.13341 |