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| Titel |
Biochar amendment decreased global warming potential of a Cd/Pb contaminated paddy ecosystem from the Tai Lake plain, China |
| VerfasserIn |
A. Zhang, Q. Hussian, L. Li, J. Zheng, G. Pan, X. Zhang, R. Bian |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250058802
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| Zusammenfassung |
| Nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4) are concerned as
the predominant biogenic greenhouse gases (GHGs) in the net GHGs balance of
agro-ecosystems. Predicting the net exchanges of these gases in a systemic approach would
be critical for assessing the effects on GHGs mitigation of environmental conditions and crop
management. Previous studies have shown a great potential of biochar amendment
to mitigate GHGs emission from croplands. Here, we report a field experiment
on biochar effects on rice production, net ecosystem exchange (NEE) and global
warming potential (GWP) in cadmium (Cd) and lead (Pb) contaminated paddy field.
Biochar was amended in 2009 before rice transplanting at rate of 0, 10, 20 and
40 t ha-1 and soil emission of CO2, ecosystem emissions of CH4 and N2O were
monitored with closed chamber method at 7 days interval throughout the whole rice
growing season (WRGS) in 2010. Soil samples were collected after rice harvest
in 2010 for analysis of soil property changes with biochar amendment. Biochar
amendment increased soil pH, soil organic carbon, total N but decreased soil bulk density.
DTPA Cd and Pb were decreased by 25.3%, 21.3% and 48.7%, and by 11.9%,
17.3% and 23.6% under biochar amendment at rates of 10 t ha-1, 20 t ha-1 and 40 t
ha-1, respectively. Total soil CO2 emission of WRGS was decreased by 16% and
24% under biochar amendment respectively at 20 and 40 t ha-1. There was a weak
correlation of total CO2 emission with DTPA Pb concentration (p=0.0642). Total WRGS
ecosystem emission of N2O was reduced by 11%, 33% and 50% under biochar
amendment at 10 t ha-1, 20 t ha-1 and 40 t ha-1, respectively while an increase by
31% in that of CH4 emission was observed only under biochar amendment at 40 t
ha-1.Overall, an consistent increase in ecosystem carbon sink was observed across
all treatments of biochar amendment as the overall GWP of the ecosystem was
decreased by 54% and 63% under biochar amendment at 20 t ha-1 and 40 t ha-1,
respectively.
Key words: biochar, net ecosystem exchange, global warming potential, cadmium and
lead contaminated paddy field |
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