地理学报 ›› 2019, Vol. 74 ›› Issue (7): 1319-1332.doi: 10.11821/dlxb201907004

• 气候变化与地表过程 • 上一篇    下一篇

全球主要河流流域碳酸盐岩风化碳汇评估

李朝君1,2,王世杰2,3,白晓永2,3(),谭秋1,李汇文2,李琴2,邓元红2,杨钰杰1,2,田诗琪1,2,胡泽银2   

  1. 1.贵州师范大学地理与环境科学学院,贵阳 550025
    2.中国科学院地球化学研究所环境地球化学国家重点实验室,贵阳 550081
    3.中国科学院普定喀斯特生态系统观测研究站,普定 562100
  • 收稿日期:2018-10-23 修回日期:2019-03-03 出版日期:2019-07-25 发布日期:2019-07-23
  • 通讯作者: 白晓永 E-mail:baixiaoyong@126.com
  • 作者简介:李朝君(1994-), 女, 山西长治人, 硕士生, 主要从事岩溶环境与自然地理研究。E-mail: lichaojune@126.com
  • 基金资助:
    喀斯特科学研究中心联合基金项目(U1612441);国家重点研发计划(2016YFC0502102);国家重点研发计划(2016YFC0502300);中国科学院“西部之光”人才培养计划A类(2018);中国科学院科技服务网络计划(KFJ-STS-ZDTP-036);国际合作局国际伙伴计划(132852KYSB20170029);国际合作局国际伙伴计划(2014-3);贵州省高层次创新型人才培养计划“十”层次人才项目([2016]5648);国家自然科学基金项目(41571130074);国家自然科学基金项目(41571130042);贵州省科技计划(2017-2966)

Estimation of carbonate rock weathering-related carbon sink in global major river basins

LI Chaojun1,2,WANG Shijie2,3,BAI Xiaoyong2,3(),TAN Qiu1,LI Huiwen2,LI Qin2,DENG Yuanhong2,YANG Yujie1,2,TIAN Shiqi1,2,HU Zeyin2   

  1. 1.School of Geography and Environmental Sciences, Guizhou Normal University, Guiyang 550025, China
    2.State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, CAS, Guiyang 550081, China
    3.Puding Karst Ecosystem Observation and Research Station, CAS, Puding 562100, Guizhou, China
  • Received:2018-10-23 Revised:2019-03-03 Online:2019-07-25 Published:2019-07-23
  • Contact: BAI Xiaoyong E-mail:baixiaoyong@126.com
  • Supported by:
    United Fund of Karst Science Research Center(U1612441);National Key Research & Development Program of China(2016YFC0502102);National Key Research & Development Program of China(2016YFC0502300);"Western Light" Talent Training Plan of Chinese Academy of Sciences (Class A 2018);Science and Technology Services Network Initiative Plan(KFJ-STS-ZDTP-036);International Cooperation Agency International Partnership Program(132852KYSB20170029);International Cooperation Agency International Partnership Program(2014-3);Guizhou High-level Innovative Talent Training Program "Ten" Level Talents Program([2016]5648);National Natural Science Foundation of China(41571130074);National Natural Science Foundation of China(41571130042);Science and Technology Plan of Guizhou Province of China(2017-2966)

摘要:

碳酸盐岩风化吸收的大气CO2主要以HCO3 -形式连续地经由河流从大陆输送到海洋,成为陆地生态系统的重要碳汇。目前主要河流流域的碳酸盐岩风化碳汇估算存在不确定性,分布格局尚不清晰。基于GEMS-GLORI全球河流数据库提供的全球10万km 2以上主要河流流域多年平均监测数据,利用水化学径流法估算出全球主要河流流域碳酸盐岩对CO2的吸收速率为0.43±0.15 Pg CO2 yr -1,平均CO2吸收通量为7.93±2.8 t km -2 yr -1。CO2吸收通量在不同气候带下差异显著,热带和暖温带CO2年吸收速率占全球主要河流流域年吸收速率的62.95%。冷温带CO2年吸收速率占全球主要河流流域的33.05%,仅次于热带地区。本文划分出全球CO2吸收通量的9个关键带,关键带的交汇处CO2吸收通量较高。喀斯特出露流域碳酸盐岩对CO2吸收通量的均值为8.50 t km -2 yr -1,约为非喀斯特流域的3倍。全球喀斯特出露流域碳酸盐岩风化碳汇在全球碳循环、水循环及碳收支平衡估算研究方面占据重要地位。

关键词: 碳酸盐岩, 碳汇评估, 全球主要河流流域, 水化学径流法

Abstract:

Atmospheric CO2 uptake by carbonate rock weathering is continuously transported from the land to the ocean by rivers in the form of HCO3 -, and it has become an important carbon sink of terrestrial ecosystems. In the existing research, the estimation and distribution of carbonate weathering-related carbon sink in global major river basins are still unclear. In this study, we collect hydrochemical and discharge data of multiyear average (runoff modulus, main ion concentration, and dissolved inorganic carbon) in large river basins over 100, 000 km 2. By using hydrochem-discharge method, we estimate that the CO2 uptake rates (Fv) of carbonate weathering in global major river basins is 0.43 ± 0.15 Pg CO2 yr -1 and the average CO2 uptake flux(F) is 7.93 ± 2.8 t km -2 yr -1. The CO2 uptake F and uptake Fv are substantially different under various climatic zones. The annual uptake Fv of tropical and warm regions accounts for 62.95% of the total annual Fv. The cold temperate zone is widely distributed, and its CO2 uptake Fv accounts for 33.05%, which is second only to the tropics. We also propose the nine critical zones of global CO2 uptake F (four in the middle and low latitudes, two in the western hemisphere and three in the eastern hemisphere). The CO2 uptake F in the intersection of the critical zones is high. The average CO2 uptake F in the karst-outcropped basins is 8.50 t km -2 yr -1, which is approximately three times that in the non-karst basins. Carbonate weathering carbon sinks in global karst-outcropped basins play an important role in the study of global carbon cycle, water cycle, and carbon budget balance estimation. On the basis of river basin scales, various factors (e.g., carbonate composition, exogenous acid, and climatic environment) for carbonate weathering carbon sinks should be considered. The hydrochem-discharge method should be further improved in future research. Moreover, the effects of the photosynthesis of river aquatic organisms on rock weathering carbon sinks should be considered, and carbonate rock weathering carbon sinks should be refined and extrapolated to the world.

Key words: carbonate rock, assessment of carbon sink, global major river basins, hydrochem-discharge method