河流溶解无机碳稳定碳同位素示踪技术及其在中国河流碳循环研究中的应用  

Reviews on Stable Isotopic Tracing Techniques of Riverine Dissolved Inorganic Carbon and Its Applications in the Study of Carbon Cycle in Chinese Rivers

作　　者：武恩鹏 孙会国[1,2] 刘文景 徐志方[1,2] WU En-peng;SUN Hui-guo;LIU Wen-jing;XU Zhi-fang(Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,P.R.China;College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,P.R.China)

机构地区：[1]中国科学院地质与地球物理研究所,新生代地质与环境院重点实验室,北京100029 [2]中国科学院大学地球与行星科学学院,北京100049

出　　处：《水生态学杂志》2024年第4期9-18,共10页Journal of Hydroecology

基　　金：国家重点研发计划项目(2020YFA0607700);国家自然科学基金项目(41877402);中国科学院青年创新促进会资助项目(Y2023014)。

摘　　要：河流溶解无机碳(DIC)是全球碳循环中的重要组成部分,稳定碳同位素(δ^(13)C_(DIC))已被广泛用于辨识流域内碳的来源和迁移转化过程。通过综合现有文献,系统梳理河流δ^(13)C_(DIC)的影响因素和变化机理,论证了该指标能够真实、敏感反映流域环境特征及各种地表过程,可用于重建流域碳循环体系中的生物地球化学过程。由于河流碳来源及迁移转化过程的复杂性,关于河流δ^(13)C_(DIC)的影响机理仍有较多细节尚未探明。通过收集和分析中国主要河流的δ^(13)C_(DIC)数据发现,在全国尺度上我国河流δ^(13)C_(DIC)呈现出“西高东低”的变化格局,基本反映了我国地质、气候及生态环境的空间分布特征。青藏高原地区河流δ^(13)C_(DIC)整体上比其他地区明显偏高,关于这一现象的形成机制还有待进一步研究。未来可将δ^(13)C与放射性碳同位素(Δ^(14)C)联用并加强水体DIC稳定碳同位素分馏方面的基础理论研究,以期进一步完善和提升河流DIC同位素示踪理论及其在揭示碳循环过程和机理方面的应用。Dissolved inorganic carbon(DIC)in rivers is an important component of the global carbon cycle.The stable carbon isotope of riverine DIC(δ^(13)C_(DIC))has been extensively used to identify the sources,migration and transformation processes of carbon in river basins.In this study,we systematically reviewed the influencing factors and change mechanisms ofδ^(13)C_(DIC) in rivers based on the latest relevant researches.It has been demonstrated thatδ^(13)C_(DIC) can faithfully and sensitively reflect the environmental characteristics of watersheds and various surface processes,making it a useful tool for reconstructing the biogeochemical processes within the watershed carbon cycle.However,due to the complexity of carbon sources and migration and transformation processes in rivers,many details regarding the influencing mechanisms of riverineδ^(13)C_(DIC) remain unclear.We also summarized the spatial distribution patterns and influencing mechanisms ofδ^(13)C_(DIC) in China's rivers based on the reportedδ^(13)C_(DIC) data from major Chinese rivers.It has been found that theδ^(13)C_(DIC) values displayed a spatial pattern of"high in the west and low in the east",basically reflecting the spatial distribution characteristics of geology,climate,and ecological environments in China.Theδ^(13)C_(DIC) values in rivers of the Tibetan Plateau were remarkably higher than those in other regions,and the underlying mechanism for this discrepancy requires further investigation.Finally,we proposed suggestions for future studies,and it is suggested to combine the use ofδ^(13)C and radiocarbon isotope(Δ^(14)C),and strengthen the basic theoretical research on the stable carbon isotope fractionation of dissolved inorganic carbon in water bodies.

关 键 词：河流溶解无机碳 稳定碳同位素 流域过程 人类活动 中国河流 

分 类 号：X522[环境科学与工程—环境工程] P593[天文地球—地球化学]