Articles | Volume 23, issue 13
https://doi.org/10.5194/bg-23-4463-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-4463-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Jul 2026
Research article |
| 06 Jul 2026
| 06 Jul 2026
Combining microbial, isotopic and residence time data to characterize groundwater dynamics in a multi-layered aquifer system in Kurikka, western Finland
Geological Survey of Finland (GTK), Espoo, 02150, Finland
Juuso Ikonen
Geological Survey of Finland (GTK), Espoo, 02150, Finland
Marie-Amélie Pétré
Geological Survey of Finland (GTK), Espoo, 02150, Finland
current address: BRGM – French Geological Survey, 45060 Orléans, France
Niko Putkinen
Geological Survey of Finland (GTK), Espoo, 02150, Finland
Jürgen Sültenfuss
University of Bremen, Otto Hahn Allee 1, 28359 Bremen, Germany
Minna Myllyperkiö
Geological Survey of Finland (GTK), Espoo, 02150, Finland
Anna-Maria Hokajärvi
Finnish Institute for Health and Welfare (THL), Department of Public Health, Kuopio, 70210, Finland
Tarja Pitkänen
Finnish Institute for Health and Welfare (THL), Department of Public Health, Kuopio, 70210, Finland
University of Helsinki, Faculty of Veterinary Medicine, Helsinki, 00014, Finland
Ilkka T. Miettinen
Finnish Institute for Health and Welfare (THL), Department of Public Health, Kuopio, 70210, Finland
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Short summary
This study explored a complex aquifer in western Finland to understand how underground water moves and what kind of microbial life it supports. By combining chemical, isotopic, and biological analyses, we found that shallow waters are younger while deeper waters are older and more isolated, and these host different microbial communities. These findings help explain how groundwater systems work and support better management of this vital resource for drinking water supply.
This study explored a complex aquifer in western Finland to understand how underground water...
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