Qu Bin, Aho Kelly Sue, Li Chaoliu, Kang Shichang, Sillanpää Mika, Yan Fangping, Raymond Peter A
Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science and Technology, Nanjing, 210044, China.
Laboratory of Green Chemistry, Lappeenranta University of Technology, Mikkeli, 50130, Finland.
Sci Rep. 2017 Nov 29;7(1):16573. doi: 10.1038/s41598-017-16552-6.
Greenhouse gases (GHGs) emissions from streams are important to regional biogeochemical budgets. This study is one of the first to incorporate stream GHGs (CO, CH and NO) concentrations and emissions in rivers of the Tibetan Plateau. With one-time sampling from 32 sites in rivers of the plateau, we found that most of the rivers were supersaturated with CO, CH and NO during the study period. Medians of partial pressures of CO (pCO), pCH and pNO were presented 864 μatm, 6.3 μatm, and 0.25 μatm respectively. Based on a scaling model of the flux of gas, the calculated fluxes of CO, CH and NO (3,452 mg-C m d, 26.7 mg-C m d and 0.18 mg-N m d, respectively) in rivers of the Tibetan Plateau were found comparable with most other rivers in the world; and it was revealed that the evasion rates of CO and CH in tributaries of the rivers of the plateau were higher than those in the mainstream despite its high altitude. Furthermore, concentrations of GHGs in the studied rivers were related to dissolved carbon and nitrogen, indicating that riverine dissolved components could be used to scale GHGs envision in rivers of the Tibetan Plateau.
河流中的温室气体（GHGs）排放对区域生物地球化学收支很重要。本研究是首批将青藏高原河流中的河流温室气体（CO、CH和NO）浓度及排放纳入其中的研究之一。通过对高原河流32个站点进行一次性采样，我们发现，在研究期间，大多数河流中的CO、CH和NO处于过饱和状态。CO（pCO）、pCH和pNO的分压中位数分别为864 μatm、6.3 μatm和0.25 μatm。基于气体通量的缩放模型，计算得出青藏高原河流中CO、CH和NO的通量（分别为3,452 mg-C m² d⁻¹、26.7 mg-C m² d⁻¹和0.18 mg-N m² d⁻¹）与世界上大多数其他河流相当；并且发现，尽管高原河流海拔较高，但其支流中CO和CH的逸出率高于主流。此外，所研究河流中的温室气体浓度与溶解碳和氮有关，这表明河流溶解成分可用于推算青藏高原河流中的温室气体含量。
