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| Titel |
Nitrous oxide emission from highland winter wheat field after long-term fertilization |
| VerfasserIn |
X. R. Wei, M. D. Hao, X. H. Xue, P. Shi, R. Horton, A. Wang, Y. F. Zang |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 7, no. 10 ; Nr. 7, no. 10 (2010-10-27), S.3301-3310 |
| Datensatznummer |
250005025
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| Publikation (Nr.) |
 copernicus.org/bg-7-3301-2010.pdf |
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| Zusammenfassung |
| Nitrous oxide (N2O) is an important greenhouse gas. N2O emissions
from soils vary with fertilization and cropping practices. The response of
N2O emission to fertilization of agricultural soils plays an important
role in global N2O emission. The objective of this study was to assess
the seasonal pattern of N2O fluxes and the annual N2O emissions
from a rain-fed winter wheat (Triticum aestivum L.) field in the Loess Plateau of China. A
static flux chamber method was used to measure soil N2O fluxes from
2006 to 2008. The study included 5 treatments with 3 replications in a
randomized complete block design. Prior to initiating N2O measurements
the treatments had received the same fertilization for 22 years. The
fertilizer treatments were unfertilized control (CK), manure (M), nitrogen
(N), nitrogen + phosphorus (NP), and nitrogen + phosphorus + manure (NPM).
Soil N2O fluxes in the highland winter wheat field were highly variable
temporally and thus were fertilization dependent. The highest fluxes
occurred in the warmer and wetter seasons. Relative to CK, m slightly
increased N2O flux while N, NP and NPM treatments significantly
increased N2O fluxes. The fertilizer induced increase in N2O flux
occurred mainly in the first 30 days after fertilization. The increases were
smaller in the relatively warm and dry year than in the cold and wet year.
Combining phosphorous and/or manure with mineral N fertilizer partly offset
the nitrogen fertilizer induced increase in N2O flux. N2O fluxes
at the seedling stage were mainly controlled by nitrogen fertilization,
while fluxes at other plant growth stages were influenced by plant and
environmental conditions. The cumulative N2O emissions were always
higher in the fertilized treatments than in the non-fertilized treatment
(CK). Mineral and manure nitrogen fertilizer enhanced N2O emissions in
wetter years compared to dryer years. Phosphorous fertilizer offset 0.50 and
1.26 kg N2O-N ha−1 increases, while manure + phosphorous offset
0.43 and 1.04 kg N2O-N ha−1 increases by N fertilizer for the two
observation years. Our results suggested that the contribution of single N
fertilizer on N2O emission was larger than that of NP and NPM and that
manure and phosphorous had important roles in offsetting mineral N
fertilizer induced N2O emissions. Relative to agricultural production
and N2O emission, manure fertilization (M) should be recommended while
single N fertilization (N) should be avoided for the highland winter wheat
due to the higher biomass and grain yield and lower N2O flux and annual
emission in m than in N. |
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