Increases in temperature and nutrient availability positively affect methane-cycling microorganisms in Arctic thermokarst lake sediments

de Jong, Anniek EE, in 't Zandt, Michiel H, Meisel, Ove H, Jetten, Mike SM, Dean, Joshua F ORCID: 0000-0001-9058-7076, Rasigraf, Olivia and Welte, Cornelia U (2018) Increases in temperature and nutrient availability positively affect methane-cycling microorganisms in Arctic thermokarst lake sediments. ENVIRONMENTAL MICROBIOLOGY, 20 (12). pp. 4314-4327.

Text 2018 de Jong et al 2018, Environmental Microbiology - Alaskan thermokarst lake methane microbiology.pdf - Published version Download (734kB)

Abstract

Arctic permafrost soils store large amounts of organic matter that is sensitive to temperature increases and subsequent microbial degradation to methane (CH ₄ ) and carbon dioxide (CO ₂ ). Here, we studied methanogenic and methanotrophic activity and community composition in thermokarst lake sediments from Utqiag˙vik (formerly Barrow), Alaska. This experiment was carried out under in situ temperature conditions (4°C) and the IPCC 2013 Arctic climate change scenario (10°C) after addition of methanogenic and methanotrophic substrates for nearly a year. Trimethylamine (TMA) amendment with warming showed highest maximum CH ₄ production rates, being 30% higher at 10°C than at 4°C. Maximum methanotrophic rates increased by up to 57% at 10°C compared to 4°C. 16S rRNA gene sequencing indicated high relative abundance of Methanosarcinaceae in TMA amended incubations, and for methanotrophic incubations Methylococcaeae were highly enriched. Anaerobic methanotrophic activity with nitrite or nitrate as electron acceptor was not detected. This study indicates that the methane cycling microbial community can adapt to temperature increases and that their activity is highly dependent on substrate availability.

Item Type:	Article
Uncontrolled Keywords:	Methylococcaceae, Methanosarcinaceae, Carbon Dioxide, Methane, RNA, Ribosomal, 16S, Temperature, Geologic Sediments, Alaska, Arctic Regions, Climate Change, Lakes, Microbiota, Nutrients
Depositing User:	Symplectic Admin
Date Deposited:	29 Nov 2018 11:45
Last Modified:	19 Jan 2023 01:11
DOI:	10.1111/1462-2920.14345
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3029189