title: Dissolved nitrous oxide and emission relating to denitrification across the Poyang Lake aquatic continuum.
abstract: Most aquatic ecosystems contribute elevated N2O to atmosphere due to increasing anthropogenic nitrogen loading. To further understand the spatial heterogeneity along an aquatic continuum from the upriver to wetland to lake to downriver, the study was conducted on spatial variations in N2O emission along Poyang Lake aquatic continuum during the flood season from 15 July 2013 to 10 August 2013. The results showed the N2O concentrations, the ratio of N2O/dinitrogen (N2) gases production, N2O emission and denitrification rates ranged from 0.10 to 1.11μgN/L, -0.007% to 0.051%, -9.73 to 127μgN/m2/hr and 1.33×104to 31.9×104μgN2/m2/hr, respectively, across the continuum. The average N2O concentrations, the ratio of N2O/N2and N2O emission was significantly lower in wetlands as compared to the rivers and lake (p<0.01). The significantly high denitrification rate and low N2O emission together highlighted that most N2O can be converted into N2via near complete denitrification in the Poyang Lake wetlands. Our study suggests that the wetlands might impact N2O budget in an integrated aquatic ecosystems. Moreover, N2O emission from different aquatic ecosystem should be considered separately when quantifying the regional budget in aquatic ecosystem.
authors.affiliation: Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China. Electronic address: wanghx.13b@igsnrr.ac.cn.
authors.forename: Huaxin
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Xue
authors.affiliation: Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: yanwj@igsnrr.ac.cn.
authors.forename: Weijin
authors.initials: W
authors.lastname: Yan
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere / Q000737:chemistry; D002681:China; D058440:Denitrification; D017753:Ecosystem; D004784:Environmental Monitoring; D060106:Lakes / Q000737:chemistry; D009609:Nitrous Oxide / Q000032:analysis*; D053833:Wetlands
chemical_list: D000393:Air Pollutants; D009609:Nitrous Oxide
keywords: Denitrification; Dinitrogen gas; Natural wetlands; Nitrogen; Nitrous oxide gas; Poyang Lake