title: Effects of straw incorporation along with microbial inoculant on methane and nitrous oxide emissions from rice fields.
abstract: Incorporation of straw together with microbial inoculant (a microorganism agent, accelerating straw decomposition) is being increasingly adopted in rice cultivation, thus its effect on greenhouse gas (GHG) emissions merits serious attention. A 3-year field experiment was conducted from 2010 to 2012 to investigate combined effect of straw and microbial inoculant on methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP) and greenhouse gas intensity (GHGI) in a rice field in Jurong, Jiangsu Province, China. The experiment was designed to have treatment NPK (N, P and K fertilizers only), treatment NPKS (NPK plus wheat straw), treatment NPKSR (NPKS plus Ruilaite microbial inoculant) and treatment NPKSJ (NPKS plus Jinkuizi microbial inoculant). Results show that compared to NPK, NPKS increased seasonal CH4 emission by 280-1370%, while decreasing N2O emission by 7-13%. When compared with NPKS, NPKSR and NPKSJ increased seasonal CH4 emission by 7-13% and 6-12%, respectively, whereas reduced N2O emission by 10-27% and 9-24%, respectively. The higher CH4 emission could be attributed to the higher soil CH4 production potential triggered by the combined application of straw and microbial inoculant, and the lower N2O emission to the decreased inorganic N content. As a whole, the benefit of lower N2O emission was completely offset by increased CH4 emission, resulting in a higher GWP for NPKSR (5-12%) and NPKSJ (5-11%) relative to NPKS. Due to NPKSR and NPKSJ increased rice grain yield by 3-6% and 2-4% compared to NPKS, the GHGI values for NPKS, NPKSR and NPKSJ were comparable. These findings suggest that incorporating straw together with microbial inoculant would not influence the radiative forcing of rice production in the terms of per unit of rice grain yield relative to the incorporation of straw alone.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, China. Electronic address: hxu@issas.ac.cn.
authors.forename: Hua
authors.initials: H
authors.lastname: Xu
authors.affiliation: Zhenjiang Institute of Agricultural Science of Hilly Regions in Jiangsu, Jurong 212400, China.
authors.forename: Qinyan
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Zhenjiang Institute of Agricultural Science of Hilly Regions in Jiangsu, Jurong 212400, China.
authors.forename: Jinghui
authors.initials: J
authors.lastname: Yang
authors.affiliation: Zhenjiang Institute of Agricultural Science of Hilly Regions in Jiangsu, Jurong 212400, China.
authors.forename: Yiqing
authors.initials: Y
authors.lastname: Zhuang
mesh_terms: D059827:Agricultural Inoculants; D000383:Agriculture / Q000379:methods*; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000517:prevention & control*; D002681:China; D057232:Global Warming; D008697:Methane / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D012275:Oryza / Q000254:growth & development
chemical_list: D000393:Air Pollutants; D009609:Nitrous Oxide; D008697:Methane
keywords: Methane; Microbial inoculant; Nitrous oxide; Rice fields; Straw incorporation