Following the flow – microbial ecology in surface- and groundwaters in the glacial forefield of a rapidly retreating glacier in Iceland

• Published in: Environmental Microbiology
• Main Authors: Purkamo, Lotta, Dochartaigh, Brighid Ó, MacDonald, Alan, Cousins, Claire
• Other Authors: The Leverhulme Trust, University of St Andrews. School of Earth & Environmental Sciences, University of St Andrews. St Andrews Centre for Exoplanet Science
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: GE Environmental Sciences; DAS; SDG 13 - Climate Action; GE; Lotta; glacier; Iceland
• Online Access: http://hdl.handle.net/10023/25677; https://doi.org/10.1111/1462-2920.16104

Travel and fieldwork in Iceland for Lotta Purkamo was funded by Sohlberg fund of The Finnish Society of Sciences and Letters. Sequencing was funded by The Leverhulme Trust (RPG-2016-153 to Claire Cousins). BGS research at Virkisjökull was funded by the BGS-NERC Earth Hazards and Observatories Directorate, and VatnajökulsÞjóðgarður provided permission to install monitoring equipment. The retreat of glaciers in response to climate change has major impacts on the hydrology and ecosystems of glacier forefield catchments. Microbes are key players in ecosystem functionality, supporting the supply of ecosystem services that glacier systems provide. The interaction between surface and groundwaters in glacier forefields has only recently gained much attention, and how these interactions influence the microbiology is still unclear. Here, we identify the microbial communities in groundwater from shallow (<15m deep) boreholes in a glacial forefield floodplain (‘sandur’) aquifer at different distances from the rapidly retreating Virkisjökull glacier, Iceland, and with varying hydraulic connectivity with the glacial meltwater river that flows over the sandur. Groundwater communities are shown to differ from those in nearby glacial and non-glacial surface water communities. Groundwater-meltwater interactions and groundwater flow dynamics affect the microbial community structure, leading to different microbial communities at different sampling points in the glacier forefield. Groundwater communities differ from those in nearby glacial and non-glacial surface waters. Functional potential for microbial nitrogen and methane cycling was detected, although the functional gene copy numbers of specific groups were low. Publisher PDF Peer reviewed