edoc

Micro-aerobic bacterial methane oxidation in the chemocline and anoxic water column of deep south-Alpine Lake Lugano (Switzerland)

Blees, Jan and Niemann, Helge and Wenk, Christine B. and Zopfi, Jakob and Schubert, Carsten J. and Kirf, Matthias T. and Veronesi, Mauro and Hitz, Carmen and Lehmann, Moritz F.. (2014) Micro-aerobic bacterial methane oxidation in the chemocline and anoxic water column of deep south-Alpine Lake Lugano (Switzerland). Limnology and oceanography, Vol. 59, H. 2. pp. 311-324.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A6233711

Downloads: Statistics Overview

Abstract

We measured seasonal variations in the vertical distribution of methane concentration, methane oxidation rates, and lipid biomarkers in the northern basin of Lake Lugano. Methane consumption below the oxic–anoxic interface co-occurred with concentration maxima of 13C-depleted C16 fatty acid biomarkers (with d13C values as low as 270%) in the anoxic water column, as well as characteristic d13CCH4 profiles. We argue that the conspicuous methane concentration gradients are primarily driven by (micro-)aerobic methane oxidation (MOx) below the chemocline. We measured a strong MOx potential throughout the anoxic water column, while MOx rates at in situ O2 concentration . 10 nmol L21 were undetectable. Similarly, we found MOx-related biomarkers and gene sequences encoding the particulate methane monooxygenase in the anoxic, but not the oxic, water. The mechanism of (episodic) oxygen supply sustaining the MOx community in anoxic waters is still uncertain. Our results indicate that a bacterial methanotrophic community is responsible for the methane consumption in Lake Lugano, without detectable contribution from archaeal methanotrophs. Bacterial populations that accumulated both at the suboxic–anoxic interface and in the deeper anoxic hypolimnion, where maximum potential MOx rates were observed throughout the year (1.5–2.5 mmol L21 d21) were mainly related to Methylobacter sp. Close relatives are found in lacustrine environments throughout the world, and their potential to thrive under micro- and anoxic conditions in Lake Lugano may imply that micro-aerobic methane oxidation is important in methane cycling and competition for methane and oxygen in stratified lakes worldwide.
Faculties and Departments:05 Faculty of Science > Departement Umweltwissenschaften > Umweltgeowissenschaften > Geochemie Stoffkreisläufe (Lehmann)
UniBasel Contributors:Blees, Jan Hendrik and Wenk, Christine and Niemann, Helge and Zopfi, Jakob and Lehmann, Moritz F
Item Type:Article, refereed
Article Subtype:Research Article
Bibsysno:Link to catalogue
Publisher:American Society of Limnology and Oceanography
ISSN:0024-3590
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:27 Mar 2014 13:13
Deposited On:27 Mar 2014 13:13

Repository Staff Only: item control page