Methane emissions from Amazonian Rivers and their contribution to the global methane budget

Author(s)

Sawakuchi, Henrique O. ^[1] ; Bastviken, David ^[2] ; Sawakuchi, Andre O. ^[3] ; Krusche, Alex V. ^[1] ; Ballester, Maria V. R. ^[1] ; Richey, Jeffrey E. ^[4]

Affiliation

^[1] Univ Sao Paulo, Ctr Nucl Energy Agr, Environm Anal & Geoproc Lab, BR-13400970 Piracicaba, SP - Brazil

^[2] Linkoping Univ, Dept Themat Studies Water & Environm Studies, SE-58183 Linkoping - Sweden

^[3] Univ Sao Paulo, Inst Geosci, Dept Sedimentary & Environm Geol, BR-05508080 Sao Paulo - Brazil

^[4] Univ Washington, Sch Oceanog, Seattle, WA 98195 - USA

• Document type: Journal article
• Source: GLOBAL CHANGE BIOLOGY; v. 20, n. 9, p. 2829-2840, SEP 2014.
• Web of Science Citations: 45

Abstract

Methane (CH4) fluxes from world rivers are still poorly constrained, with measurements restricted mainly to temperate climates. Additional river flux measurements, including spatio-temporal studies, are important to refine extrapolations. Here we assess the spatio-temporal variability of CH4 fluxes from the Amazon and its main tributaries, the Negro, Solimoes, Madeira, Tapajos, Xingu, and Para Rivers, based on direct measurements using floating chambers. Sixteen of 34 sites were measured during low and high water seasons. Significant differences were observed within sites in the same river and among different rivers, types of rivers, and seasons. Ebullition contributed to more than 50% of total emissions for some rivers. Considering only river channels, our data indicate that large rivers in the Amazon Basin release between 0.40 and 0.58 Tg CH4 yr(-1). Thus, our estimates of CH4 flux from all tropical rivers and rivers globally were, respectively, 19-51% to 31-84% higher than previous estimates, with large rivers of the Amazon accounting for 22-28% of global river CH4 emissions. (AU)

• FAPESP's process: 12/17359-9 - Methane flux from rivers and different approaches for estimate methane production and oxidation from inland water systems
• Grantee: Henrique Oliveira Sawakuchi
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 11/14502-2 - Regulating factors of methane (CH4) emission in depositional environments of the Rivers Negro, Tapajos, Xingu and Amazonas
• Grantee: Henrique Oliveira Sawakuchi
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/06609-1 - Provenance, transport and storage of sediments in Amazon rivers
• Grantee: André Oliveira Sawakuchi
• Support Opportunities: Regular Research Grants
• FAPESP's process: 08/58089-9 - The role of rivers on the regional carbon cycle
• Grantee: Maria Victoria Ramos Ballester
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants