Articles | Volume 23, issue 3
https://doi.org/10.5194/bg-23-1013-2026
© 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-23-1013-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Feb 2026
Research article |
| 04 Feb 2026
| 04 Feb 2026
BrGDGT-based palaeothermometer in drylands: the necessity to constrain aridity and salinity as confounding factors to ensure the robustness of calibrations
Lucas Dugerdil
CORRESPONDING AUTHOR
ISEM, University of Montpellier, CNRS, IRD, Montpellier, France
ENS de Lyon, Université Lyon 1, CNRS, UMR 5276 LGL-TPE, Lyon, France
Sébastien Joannin
ISEM, University of Montpellier, CNRS, IRD, Montpellier, France
Odile Peyron
ISEM, University of Montpellier, CNRS, IRD, Montpellier, France
Shafag Bayramova
Institute of Geology and Geophysics, Department of modern geodynamics and space geodesy, Baku, Azerbaijan
Xiaozhong Huang
Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, China
Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Changes, Faculty of Geography, Yunnan Normal University, Kunming, China
Fahu Chen
Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, China
Alpine Paleoecology and Human Adaptation Group, State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
Dilfuza Egamberdieva
Medical School, Central Asian University, Tashkent 111221, Uzbekistan
Faculty of Biology and Ecology, National University of Uzbekistan, Tashkent 100174, Uzbekistan
Jakhongir Alimov
Faculty of Biology and Ecology, National University of Uzbekistan, Tashkent 100174, Uzbekistan
International Agriculture University, Kibray district, 100164, Tashkent, Uzbekistan
Bazartseren Boldgiv
Ecology Group, Department of Biology, School of Arts and Sciences, National University of Mongolia, Ulaanbaatar 14201, Mongolia
Amy Cromartie
Université Côte d’Azur, CNRS, CEPAM, UMR 7264, 06300, Nice, France
ISEM, University of Montpellier, CNRS, IRD, Montpellier, France
Juzhi Hou
Alpine Paleoecology and Human Adaptation Group, State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
Lilit Sahakyan
Institute of Geological Sciences of Armenia, of the National Academy of Sciences of the Republic of Armenia, ave. M. Baghramyan 24a, Yerevan 0019, Armenia
Khachatur Meliksetian
Institute of Geological Sciences of Armenia, of the National Academy of Sciences of the Republic of Armenia, ave. M. Baghramyan 24a, Yerevan 0019, Armenia
Salomé Ansanay-Alex
ENS de Lyon, Université Lyon 1, CNRS, UMR 5276 LGL-TPE, Lyon, France
Rafig Safarov
Institute of Geology and Geophysics, Science and Education Ministry of Azerbaijan Republic, AZ1073, Baku, Azerbaijan
Imran Muradi
Institute of Geology and Geophysics, Science and Education Ministry of Azerbaijan Republic, AZ1073, Baku, Azerbaijan
Shabnam Isayeva
Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
Shehla Mirzayeva
Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
Elshan Abdullayev
Institute of Geography and Geology, University of Greifswald, Friedrich-Ludwig-Jahn Strasse 17A, 17487 Greifswald, Germany
Department of Life Sciences, Khazar University, 41 Mahsati Str., AZ1096 Baku, Azerbaijan
Sayyara Ibadullayeva
Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
Parvana Garakhani
Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
Guillemette Ménot
CORRESPONDING AUTHOR
ENS de Lyon, Université Lyon 1, CNRS, UMR 5276 LGL-TPE, Lyon, France
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Short summary
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial lipids preserved in soils and sediments, used as climate proxies. This study presents the Arid Central Asian brGDGT surface database to assess their reliability in drylands. Results show that salinity, sample type, pH, and aridity strongly influence brGDGT signals, limiting temperature reconstructions. Refined calibrations improve reconstruction accuracy, and methylation index differences may indicate aridity variations.
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial lipids preserved in soils...
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