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conferenceseries
.com
Volume 8, Issue 10 (Suppl)
J Earth Sci Clim Change, an open access
ISSN: 2157-7617
Climate Change 2017
October 19-21, 2017
CLIMATE CHANGE
October 19-21, 2017 | Rome, Italy
4
th
World Conference on
Stable carbon isotopes of CH
4
emission from three typical rice fields in China
Guangbin Zhang
1
, Ma Jing
1
, Yang Yuting
1,2
, Yu Haiyang
1,2
, Shi Yaping
1,2
,
and
Xu Hua
1
1
Chinese Academy of Sciences, China
2
University of Chinese Academy of Sciences, China
L
ittle is known about the stable carbon isotopes of CH
4
emission (δ
13
CH
4
emitted) from permanently flooded rice field and
double-rice field. CH
4
fluxes and corresponding δ
13
CH
4
emitted under various field managements (mulching, water regime,
tillage, and nitrogen (N) fertilization) were simultaneously measured in three typical Chinese rice fields, a permanently flooded
rice field in Ziyang City, Sichuan Province, Southwest China, a double-rice cropping field in Yingtan City, Jiangxi Province,
Southeast China, and a rice-wheat rotation field in Jurong City, Jiangsu Province, East China, from 2010 to 2012. Results
showed different seasonal variations of δ
13
CH
4
emitted from the three fields during the rice-growing season. The values of
δ
13
CH
4
emitted were negatively correlated with corresponding CH4 emissions in seasonal variation and mean, indicating the
importance of CH
4
production, oxidation and transport associated with isotopic fractionation effects to theδ13CH4emitted.
Seasonal variations of δ
13
CH
4
emitted were slightly impacted by mulching cultivation, tillage and N application but highly
controlled by drainage. Meanwhile, tillage and N application, especially mulching cultivation, played important roles in mean
CH
4
emissions and corresponding δ
13
CH
4
emitted, resulting in low emissions with high values of δ
13
CH
4
. Totally, mean values
of δ
13
CH
4
emitted from the three fields were similar, mostly ranging from −60% to −50%, which is in good agreement with
previously published data from India and America. The results demonstrated that seasonal variations of δ
13
CH
4
emitted mainly
depended on the changes in CH
4
emission from paddy fields and further indicated that the methanogenic pathways, fraction of
CH
4
oxidation, and transport isotope fractionation influenced by field managements had important effects on δ
13
CH
4
emitted.
Biography
Guangbin Zhang major study was the processes of CH
4
emission from rice fields with the stable carbon isotope technique combining with microbes (methanogens
and methanotrophs) analyses. Recently, he had carried out field experiments to study the mechanism of CH
4
emission from a special kind of rice fields that are
permanently flooded with highest fluxes in southeast of China. In addition, pot and incubation experiments were performed to investigate the effect of nitrogen
fertilization on production, oxidation and emission of the CH
4
by measuring the stable carbon isotopes, methanogens and methanotrophs. Meanwhile, integrated
effects of nitrogen fertilization and straw application on N
2
O emission from paddy soils were observed. He is very interested in Soil Ecology, Microbiology,
Biogeochemistry, Environmental and Soil Chemistry, and his focus is on the cycling of C and N in the agricultural ecosystem and the responses to global climate
change (CO
2
concentration and temperature enrichment).
gbzhang@issas.ac.cnGuangbin Zhang et al., J Earth Sci Clim Change 2017, 8:10(Suppl)
DOI: 10.4172/2157-7617-C1-037