文献类型：期刊文献

英文题名：Headwater stream ecosystem: an important source of greenhouse gases to the atmosphere

作者：Li, Mingxu[1] Peng, Changhui[2,4] Zhang, Kerou[3] Xu, Li[1] Wang, Jianming[1] Yang, Yan[1] Li, Peng[2] Liu, Zelin[2] He, Nianpeng[1]

第一作者：Li, Mingxu

通信作者：He, NP[1];Peng, CH[2];Peng, CH[3]

机构：[1]Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China;[2]Hunan Normal Univ, Coll Resources & Environm Sci, Changsha 410081, Peoples R China;[3]Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China;[4]Univ Quebec, Inst Environm Sci, Dept Biol Sci, CP 8888,Succ Ctr Ville, Montreal, PQ H3C 3P8, Canada

年份：2021

卷号：190

外文期刊名：WATER RESEARCH

收录：;EI(收录号：20205109655027);Scopus(收录号：2-s2.0-85097800391);WOS:【SCI-EXPANDED(收录号:WOS:000632807700045)】；

基金：This work was supported by the Second Tibetan Plateau Scientific Expedition and Research Program (2019QZKK060602), the National Key R&D Program of China (2017YFA0604803), and Natural Science Foundation in China (31988102). We would like to thank Editage (www.editage.cn) for English language editing. The compiled global database can be found in Appendix B, containing riverine GHG measurements and related environment information (e.g., DO, DOC, DIC, etc.). Any additional data supporting the findings of this study is available by contacting the first author (mingxuli@igsnrr.ac.cn).

语种：英文

外文关键词：Riverine GHG emissions; Stream order; Headwater stream oxygen level; Carbon/Nitrogen input

摘要：Although an increasing number of reports have revealed that rivers are important sources of greenhouse gases (GHGs), the magnitude and underlying mechanism of riverine GHG emissions are still poorly understood. The global extent of the headwater stream ecosystem may represent one of the important GHG emitters. A global database of GHG measurements from 595 rivers, indicated that the concentrations of riverine GHGs continually decrease as the stream order increases. Further analysis suggested that high GHG emissions from headwater streams (Strahler stream orders of 1 to 3) could be related to the low levels of dissolved oxygen, massive terrestrially derived carbon/nitrogen inputs and large gas exchange velocity. Through a combination of the predicted river surface areas and gas transfer velocities, we estimated that globally, the rivers emit approximately 6.6 (5.5-7.8) Pg CO2, 29.5 (19.6-37.3) Tg CH4, and 0.6 (0.2-0.9) Tg N2O per year, and totally emit 7.6 (6.1-9.1) CO2 equivalent into atmosphere per year. The headwater streams contribute 72.3%, 75.5%, and 77.2% of the global riverine CO2, CH4, and N2O emissions, respectively. This study presents a systematic estimation of GHG emissions from river ecosystems worldwide and highlights the dominant role played by headwater streams in GHG evasions from global rivers. (c) 2020 Elsevier Ltd. All rights reserved.