TY - JOUR
T1 - Temperature differently affected methanogenic pathways and microbial communities in sub-Antarctic freshwater ecosystems
AU - LAVERGNE, CÉLINE
AU - Aguilar-Muñoz, Polette
AU - Calle, Natalia
AU - Thalasso, Frédéric
AU - Astorga-España, Maria Soledad
AU - Sepulveda-Jauregui, Armando
AU - Martinez-Cruz, Karla
AU - Gandois, Laure
AU - Mansilla, Andrés
AU - CHAMY MAGGI, ROLANDO ARTURO
AU - Barret, Maialen
AU - Cabrol, Léa
N1 - Funding Information:
We acknowledge the French ministries MAEDI (Minist?re des Affaires Etrang?res et du D?veloppement International) and MENESR (Minist?re de l'?ducation nationale, de l'Enseignement sup?rieur et de la Recherche) as well as Chilean CONICYT (Comisi?n Nacional de Investigaci?n Cient?fica y Tecnol?gica) for financial support through the ERANet-LAC joint program METHANOBASE (ELAC2014_DCC-0092). Authors are grateful to Tamara Contador's Laboratory for support in the field during the sampling expedition in Puerto Williams, Chile. We also thank the Genotoul platform (Toulouse, France) for the high throughput sequencing service, and the PAPC platform (EcoLab laboratory) for major elements analysis. The authors acknowledge the anonymous reviewers for their thoughtful comments and constructive suggestions.
Funding Information:
We acknowledge the French ministries MAEDI (Ministère des Affaires Etrangères et du Développement International) and MENESR (Ministère de l'Éducation nationale, de l'Enseignement supérieur et de la Recherche) as well as Chilean CONICYT (Comisión Nacional de Investigación Científica y Tecnológica) for financial support through the ERANet-LAC joint program METHANOBASE ( ELAC2014_DCC-0092 ). Authors are grateful to Tamara Contador’s Laboratory for support in the field during the sampling expedition in Puerto Williams, Chile. We also thank the Genotoul platform (Toulouse, France) for the high throughput sequencing service, and the PAPC platform (EcoLab laboratory) for major elements analysis. The authors acknowledge the anonymous reviewers for their thoughtful comments and constructive suggestions.
Funding Information:
This work was supported by ERANET-LAC project METHANOBASE [ELAC2014 DCC0092, 2016–2019] and the “Instituto Antártico Chileno” (INACH) project [RT_14-15, 2016–2019]. Mobility was funded by ECOS Sud-CONICYT Project “MATCH” [C16B03, 2017–2020]. Céline Lavergne was funded by Chilean Ministry of science, technology, knowledge and innovation [ANID FONDECYT grants 3180374 and 11201072]. Polette Aguilar-Muñoz was granted by Chilean Ministry of science, technology, knowledge and innovation [ANID National Doctoral grant 21161068].
Publisher Copyright:
© 2021 The Authors
PY - 2021/9
Y1 - 2021/9
N2 - Freshwater ecosystems are responsible for an important part of the methane (CH4) emissions which are likely to change with global warming. This study aims to evaluate temperature-induced (from 5 to 20 °C) changes on microbial community structure and methanogenic pathways in five sub-Antarctic lake sediments from Magallanes strait to Cape Horn, Chile. We combined in situ CH4 flux measurements, CH4 production rates (MPRs), gene abundance quantification and microbial community structure analysis (metabarcoding of the 16S rRNA gene). Under unamended conditions, a temperature increase of 5 °C doubled MPR while microbial community structure was not affected. Stimulation of methanogenesis by methanogenic precursors as acetate and H2/CO2, resulted in an increase of MPRs up to 127-fold and 19-fold, respectively, as well as an enrichment of mcrA-carriers strikingly stronger under acetate amendment. At low temperatures, H2/CO2-derived MPRs were considerably lower (down to 160-fold lower) than the acetate-derived MPRs, but the contribution of hydrogenotrophic methanogenesis increased with temperature. Temperature dependence of MPRs was significantly higher in incubations spiked with H2/CO2 (c. 1.9 eV) compared to incubations spiked with acetate or unamended (c. 0.8 eV). Temperature was not found to shape the total microbial community structure, that rather exhibited a site-specific variability among the studied lakes. However, the methanogenic archaeal community structure was driven by amended methanogenic precursors with a dominance of Methanobacterium in H2/CO2-based incubations and Methanosarcina in acetate-based incubations. We also suggested the importance of acetogenic H2-production outcompeting hydrogenotrohic methanogenesis especially at low temperatures, further supported by homoacetogen proportion in the microcosm communities. The combination of in situ-, and laboratory-based measurements and molecular approaches indicates that the hydrogenotrophic pathway may become more important with increasing temperatures than the acetoclastic pathway. In a continuously warming environment driven by climate change, such issues are crucial and may receive more attention.
AB - Freshwater ecosystems are responsible for an important part of the methane (CH4) emissions which are likely to change with global warming. This study aims to evaluate temperature-induced (from 5 to 20 °C) changes on microbial community structure and methanogenic pathways in five sub-Antarctic lake sediments from Magallanes strait to Cape Horn, Chile. We combined in situ CH4 flux measurements, CH4 production rates (MPRs), gene abundance quantification and microbial community structure analysis (metabarcoding of the 16S rRNA gene). Under unamended conditions, a temperature increase of 5 °C doubled MPR while microbial community structure was not affected. Stimulation of methanogenesis by methanogenic precursors as acetate and H2/CO2, resulted in an increase of MPRs up to 127-fold and 19-fold, respectively, as well as an enrichment of mcrA-carriers strikingly stronger under acetate amendment. At low temperatures, H2/CO2-derived MPRs were considerably lower (down to 160-fold lower) than the acetate-derived MPRs, but the contribution of hydrogenotrophic methanogenesis increased with temperature. Temperature dependence of MPRs was significantly higher in incubations spiked with H2/CO2 (c. 1.9 eV) compared to incubations spiked with acetate or unamended (c. 0.8 eV). Temperature was not found to shape the total microbial community structure, that rather exhibited a site-specific variability among the studied lakes. However, the methanogenic archaeal community structure was driven by amended methanogenic precursors with a dominance of Methanobacterium in H2/CO2-based incubations and Methanosarcina in acetate-based incubations. We also suggested the importance of acetogenic H2-production outcompeting hydrogenotrohic methanogenesis especially at low temperatures, further supported by homoacetogen proportion in the microcosm communities. The combination of in situ-, and laboratory-based measurements and molecular approaches indicates that the hydrogenotrophic pathway may become more important with increasing temperatures than the acetoclastic pathway. In a continuously warming environment driven by climate change, such issues are crucial and may receive more attention.
KW - 16S rRNA amplicons
KW - Archaea
KW - Bacteria
KW - Global warming
KW - Limnology
KW - Methane
UR - http://www.scopus.com/inward/record.url?scp=85104684799&partnerID=8YFLogxK
U2 - 10.1016/j.envint.2021.106575
DO - 10.1016/j.envint.2021.106575
M3 - Article
AN - SCOPUS:85104684799
VL - 154
JO - Environment International
JF - Environment International
SN - 0160-4120
M1 - 106575
ER -