Reconstructing landscape, climate and human history in semi-arid Mongolia using a multi-proxy biomarker approach

Short Description

• Project applicant: Dr. Marcel Bliedtner
• founded by: Deutsche Forschungsgemeinschaft
• DFG-GEPRISExterner Link

Semi-arid regions such as Mongolia are highly sensitive for the consequences of global warming and strongly increased human activity, and a better understanding about past climate and anthropogenic influences in such regions is essential. To address those issues, our DFG project aims at reconstructing climate and human-induced landscape changes in semi-arid Mongolia, and to disentangle between both effects by using a multi-proxy biomarker approach on lake sediments. The project uses the very promising ~7.5 ka lake sediments from Shireet Naiman Nuur (Nuur = lake), an endorheic high-altitude lake (2,429 m a.s.l.) with a small catchment in the central Mongolian Khangai Mountains. Beside state of the art sedimentological and geochemical analyzes, a multi-biomarker approach is applied to the sediments aiming the following: i.) Establishing the best possible chronology by ¹⁴C-dating of terrestrial macrofossils and compound-specific radiocarbon analyses of specific biomarker compounds which will further be evaluated and confirmed by paleomagnetic secular variations. Comparison of the different ¹⁴C-ages will give valuable chronological information about the timing of sediment deposition, but also potential transfer times of organic/biomarker material through the catchment. ii.) The presence of humans and their livestock in the lake catchment and their potential influence on landscape changes and soil erosion will directly be traced by fecal biomarker analyzes. iii.) The paleoclimatic background signal will finally be reconstructed by compound-specific isotope analyzes of δ²H on terrestrial and aquatic biomarkers to disentangle climatic and anthropogenic signals.

Publications

• Bliedtner, M., Strobel, P., Struck, J., Prochnow, M., Bazarradnaa, E., Zech, R., 2023. Mid to Late Holocene moisture evolution of semi-arid Mongolia and its anti-phase relationship with monsoonal Asia. Quaternary Science Reviews 313, 108201. https://doi.org/10.1016/j.quascirev.2023.108201Externer Link
• Bliedtner, M., Strobel, P., Struck, J., Salazar, G., Szidat, S., Nowaczyk, N., Bazarradnaa, E., Lloren, R., Dubois, N., Haberzettl, T., Zech, R., 2022. Holocene Temperature Variations in Semi-Arid Central Mongolia—A Chronological and Sedimentological Perspective From a 7400-year Lake Sediment Record From the Khangai Mountains. Frontiers in Earth Science 10.  https://doi.org/10.3389/feart.2022.910782Externer Link

You might have a look at our other related paleoclimate and proxy calibration studies from Mongolia and the Altai region:

• Bliedtner, M., Haberzettl, T., Nowaczyk, N., Bazarradnaa, E., Zech, R., Strobel, P., 2023. Assessing lock-in depth and establishing a Late Holocene paleomagnetic secular variation record from the Mongolian Altai. Radiocarbon, 1–12. https://doi.org/10.1017/RDC.2023.38Externer Link
• Struck, J., Bliedtner, M., Strobel, P., Taylor, W., Biskop, S., Plessen, B., Klaes, B., Bittner, L., Jamsranjav, B., Salazar, G., Szidat, S., Brenning, A., Bazarradnaa, E., Glaser, B., Zech, M., Zech, R., 2022. Central Mongolian lake sediments reveal new insights on climate change and equestrian empires in the Eastern Steppes. Scientific reports 12(1). https://doi.org/10.1038/s41598-021-93765-wExterner Link
• Bliedtner, M., Struck, J., Strobel, P., Salazar, G., Szidat, S., Bazarradnaa, E., Lloren, R., Dubois, N., Zech, R., 2021. Late Holocene Climate Changes in the Altai Region Based on a First High‐Resolution Biomarker Isotope Record From Lake Khar Nuur. Geophysical Research Letters 48(20). https://doi.org/10.1029/2021GL094299Externer Link
• Struck, J., Bliedtner, M., Strobel, P., Bittner, L., Bazarradnaa, E., Andreeva, D., Zech, W., Glaser, B., Zech, M., Zech, R., 2020. Leaf Waxes and Hemicelluloses in Topsoils Reflect the δ²H and δ¹⁸O Isotopic Composition of Precipitation in Mongolia. Frontiers in Earth Science 8. https://doi.org/10.3389/feart.2020.00343Externer Link
• Strobel, P., Struck, J., Zech, R., Bliedtner, M., 2021. The spatial distribution of sedimentary compounds and their environmental implications in surface sediments of Lake Khar Nuur (Mongolian Altai). Earth Surface Processes and Landforms 55, 319. https://doi.org/10.1002/esp.5049Externer Link
• Strobel, P., Struck, J., Bazarradnaa, E., Zech, M., Zech, R., Bliedtner, M., 2022. Precipitation and Lake Water Evaporation Recorded by Terrestrial and Aquatic n‐Alkane δ²H Isotopes in Lake Khar Nuur, Mongolia. Geochemistry, Geophysics, Geosystems 23(2). https://doi.org/10.1029/2021GC010234Externer Link