title: Effects of Land-Use Conversion from Double Rice Cropping to Vegetables on Methane and Nitrous Oxide Fluxes in Southern China.
abstract: Compared with CO2, methane (CH4) and nitrous oxide (N2O) are potent greenhouse gases in terms of their global warming potentials. Previous studies have indicated that land-use conversion has a significant impact on greenhouse gas emissions. However, little is known regarding the impact of converting rice (Oryza sativa L.) to vegetable fields, an increasing trend in land-use change in southern China, on CH4 and N2O fluxes. The effects of converting double rice cropping to vegetables on CH4 and N2O fluxes were examined using a static chamber method in southern China from July 2012 to July 2013. The results indicate that CH4 fluxes could reach 31.6 mg C m-2 h-1 under rice before land conversion. The cumulative CH4 emissions for fertilized and unfertilized rice were 348.9 and 321.0 kg C ha-1 yr-1, respectively. After the land conversion, the cumulative CH4 emissions were -0.4 and 1.4 kg C ha-1 yr-1 for the fertilized and unfertilized vegetable fields, respectively. Similarly, the cumulative N2O fluxes under rice were 1.27 and 0.56 kg N ha-1 yr-1 for the fertilized and unfertilized treatments before the land conversion and 19.2 and 8.5 kg N ha-1 yr-1, respectively, after the land conversion. By combining the global warming potentials (GWPs) of both gases, the overall land-use conversion effect was minor (P = 0.36) with fertilization, but the conversion reduced GWP by 63% when rice and vegetables were not fertilized. Increase in CH4 emissions increased GWP under rice compared with vegetables with non-fertilization, but increased N2O emissions compensated for similar GWPs with fertilization under rice and vegetables.
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|College of Life Sciences, Anhui Normal University, Wuhu, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|Jiangxi Provincial Key Laboratory of Ecosystem Processes and Information, Taihe, China.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Dai
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|Jiangxi Provincial Key Laboratory of Ecosystem Processes and Information, Taihe, China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Wang
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ 08901, United States of America.
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|Jiangxi Provincial Key Laboratory of Ecosystem Processes and Information, Taihe, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Fu
authors.affiliation: Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.|Jiangxi Provincial Key Laboratory of Ecosystem Processes and Information, Taihe, China.
authors.forename: Fengting
authors.initials: F
authors.lastname: Yang
mesh_terms: D057486:Carbon Cycle; D058572:Carbon Footprint; D000069599:Crop Production / Q000379:methods* / Q000592:standards; D057232:Global Warming; D008697:Methane / Q000032:analysis; D058458:Nitrogen Cycle; D009609:Nitrous Oxide / Q000032:analysis; D012275:Oryza / Q000254:growth & development*; D010087:Oxides / Q000032:analysis; D014675:Vegetables / Q000254:growth & development*
chemical_list: D010087:Oxides; D009609:Nitrous Oxide; D008697:Methane