Abstract
China accounts for a third of global nitrogen fertilizer consumption. Under an International Panel on
Climate Change (IPCC) Tier 2 assessment, emission factors (EFs) are developed for the major crop types
using country-specific data. IPCC advises a separate calculation for the direct nitrous oxide (N2O)
emissions of rice cultivation from that of cropland and the consideration of the water regime used for
irrigation. In this paper we combine these requirements in two independent analyses, using different
data quality acceptance thresholds, to determine the influential parameters on emissions with which to
disaggregate and create N2O EFs. Across China, the N2O EF for lowland horticulture was slightly higher
(between 0.74% and 1.26% of fertilizer applied) than that for upland crops (values ranging between 0.40%
and 1.54%), and significantly higher than for rice (values ranging between 0.29% and 0.66% on temporarily
drained soils, and between 0.15% and 0.37% on un-drained soils). Higher EFs for rice were associated
with longer periods of drained soil and the use of compound fertilizer; lower emissions were
associated with the use of urea or acid soils. Higher EFs for upland crops were associated with clay soil,
compound fertilizer or maize crops; lower EFs were associated with sandy soil and the use of urea.
Variation in emissions for lowland vegetable crops was closely associated with crop type. The two independent
analyses in this study produced consistent disaggregated N2O EFs for rice and mixed crops,
showing that the use of influential cropping parameters can produce robust EFs for China.
© 2015 Published by Elsevier Ltd.
Original language | English |
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Pages (from-to) | 272 - 281 |
Number of pages | 10 |
Journal | Atmospheric Environment |
Volume | 122 |
DOIs | |
Publication status | First published - 2015 |
Bibliographical note
1023515Keywords
- Agriculture
- China
- Emission factor
- Fertilizer
- Greenhouse gas
- Nitrous oxide