Decadal shifts in Qingzang Plateau lake carbon dynamics (1970-2020): From predominant carbon sources to emerging sinks  

作　　者：Di Shen Yu Li Yafeng Wang Shouliang Huo Yong Liu Junjie Jia Shuoyue Wang Kun Sun Yang Gao 

机构地区：[1]College of Earth and Environment Science,Lanzhou University,Lanzhou,730000,PR China [2]State Key Laboratory of Tibetan Plateau Earth System,Environment and Resources(TPESER),Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing,100101,PR China [3]Chinese Research Academy of Environmental Sciences,Beijing,100012,PR China [4]College of Environmental Sciences and Engineering,Peking University,Beijing,1008714,PR China [5]Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing,100101,PR China [6]College of Resources and Environment,University of Chinese Academy of Sciences,Beijing,100049,PR China

出　　处：《Environmental Science and Ecotechnology》2024年第5期123-132,共10页环境科学与生态技术（英文）

基　　金：supported by the National Nature Science Foundation of China(No.31988102,42225103 and 42141015);the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-037).

摘　　要：The evasion of carbon dioxide(CO_(2))from lakes significantly influences the global carbon equilibrium.Amidst global climatic transformations,the role of Qingzang Plateau(QZP)lakes as carbon(C)sources or sinks remains a subject of debate.Furthermore,accurately quantifying their contribution to the global carbon budget presents a formidable challenge.Here,spanning half a century(1970e2020),we utilize a synthesis of literature and empirical field data to assess the CO_(2) exchange flux of QZP lakes.We find markedly higher CO_(2) exchange flux in the southeast lakes than that in the northern and western regions from 1970 to 2000.During this time,both freshwater and saltwater lakes served primarily as carbon sources.The annual CO_(2) exchange flux was estimated at 2.04±0.37 Tg(Tg)C yr1,mainly influenced by temperature fluctuations.The CO_(2) exchange flux patterns underwent a geographical inversion between 2000 and 2020,with increased levels in the west and decreased levels in the east.Notably,CO_(2) emissions from freshwater lakes diminished,and certain saltwater lakes in the QTP transitioned from carbon sources to sinks.From 2000 to 2020,the annual CO_(2) exchange flux from QZP lakes is estimated at 1.34±0.50 Tg C yr1,with solar radiation playing a more pronounced role in carbon emissions.Cumulatively,over the past five decades,QZP lakes have generally functioned as carbon sources.Nevertheless,the total annual CO_(2) emissions have declined since the year 2000,indicating a potential shift trend from being a carbon source to a sink,mirroring broader patterns of global climate change.These findings not only augment our understanding of the carbon cycle in plateau aquatic systems but also provide crucial data for refining China's carbon budget.

关 键 词：Carbon source Carbon sink Carbon exchange flux Qingzang Plateau Global climate change 

分 类 号：X524[环境科学与工程—环境工程]