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Agricultural tillage practices play an important role in the production and/or consumption of green house gas (GHG) that contributes substantially to the observed global warming. Central China is one of the world's major rice producing areas but a few studies have tried to characterize the mechanisms of GHG release from rice paddy field and quantify global warming (GWPs) based on GHGs emission on this region. In this study four tillage systems consisting of no-tillage with no fertilizer (NT0), conventional tillage with no fertilizer (CT0), no-tillage with compound fertilizer (NTC) and conventional tillage with compound fertilizer (CTC) applications in rice ( Oryza sativa L.) cultivation were compared in terms of the carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) emissions from different tillage systems of the subtropical region of China during the rice growing season in 2008. GWPs based on CO 2 , CH 4 and N 2 O's cumulative emissions were also compared. Tillage and fertilization had no influence on CO 2 emissions. No-tillage had no effect on N 2 O emissions but significantly affected CH 4 emissions. Application of fertilizer significantly affected CH 4 and N 2 O emissions. Higher CH 4 emissions and lower N 2 O emissions were observed in CTC than in NTC. Cumulative CH 4 emission flux in NTC was 51.68 g CH 4 m −2 while it was 65.96 g CH 4 m −2 in CTC, 28% ( p 2 O emission flux in CTC was 561.00 mg N 2 O m −2 , and was 741.71 mg N 2 O m −2 in NTC, 33% ( p 2 O emissions between NT0 and CT0 systems, but significant in CH 4 emissions. GWP of CTC was 26011.58 kg CO 2 ha −1 , which was 12% higher than that in NTC (23361.3 kg CO 2 ha −1 ), therefore our findings show that no-tillage system was an effective strategy to reduce GWP from rice paddies in central China and thus can serve as a good agricultural system for environmental conservation. |
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