Research interests:

I focus on soil organic matter dynamics and biomarker studies in arid and hyperarid environments. My research addresses archaeological and paleoenvironmental questions, including the reconstruction of vegetation, fire history, and land use.

Selected projects:

CRC1211 (Earth Evolution at the dry limit): https://sfb1211.uni-koeln.de

FOR5438 (Urban Impacts on the Mongolian Plateau): https://www.for5438.uni-bonn.de

Publications

• Ma, N.,  Sun, L., Xu, Y., Li, S., Li, J., Xue, P., Yang, H., Mörchen, R., Wang, J. (2025). Soil Fertility and Maize Residue Quality All Effect the Exogenous Carbon Sequestration Only in the Short Term in Macroaggregates, but Not in Microaggregates, Agronomy 2025, 15(4), 806; https://doi.org/10.3390/agronomy15040806

• Du, L., Bauke, S.L., Mörchen, R., Schmittmann, O., Amelung, W. (2025). Fungal necromass is vital for the storage of subsoil C after deep injection of compost, Soil and Tillage Research, 245, 2025, 106325. https://doi.org/10.1016/j.still.2024.106325

• Gwozdz, M., Stolz, A., Jaeschke, A., Heinze, S., Mörchen, R., Dewald, A., Rethemeyer, J.,  Mücher, D., Schiffer, M. (2024). First δ13C Results with a New Connection Between the Ea-Irms System and the Gas Injection System at CologneAMS, Radiocarbon. 2024;66(5):1140-1151. https://doi.org/10.1017/RDC.2024.74

• Mörchen, R., Rahimova, H., Fuentes, B., Arenas-Diaz, F., Bol, R., Lehndorff. E. (2024). Organic matter imports to the Atacama Desert using polycyclic aromatic hydrocarbons as a tracer. Global and Planetary Change 235, 104394. https://doi.org/10.1016/j.gloplacha.2024.104394

• Jaeschke, A., May, S.M., Hakobyan, A., Mörchen, R., Bubenzer, O., Bernasconi, S., Schefuß, E., Hoffmeister, D., Latorre, C., Gwozdz, M., Rethemeyer, J., Knief, C. (2024). Microbial hotspots in a relict fog-dependent Tillandsia landbeckii dune from the coastal Atacama Desert. Global and Planetary Change 234, 104383. https://doi.org/10.1016/j.gloplacha.2024.104383

• Sun, X., Amelung, W., Klumpp, E., Walk, J., Mörchen, R., Böhm, C., Moradi, G., May, M., Tamburini, F., Wang, Y., Bol, R. (2023). Fog controls biological cycling of soil phosphorus in the Coastal Cordillera of the Atacama Desert. Global Change Biology; 30, 17068. https://doi.org/10.1011/gcb.17068 .

• Walk, J., Schulte, P., Bartz, M., Binnie, A., Kehl, M., Mörchen, R., Sun, X., Stauch, G., Tittmann, C., Bol, R., Brückner, H., Lehmkuhl, F. (2023). Pedogenesis at the coastal arid-hyperarid transition deduced from a Late Quaternary chronosequence at Paposo, Atacama Desert, CATENA, 228, 2023, 107171, ISSN 0341-8162. https://doi.org/10.1016/j.catena.2023.107171 .

• Sandhage-Hofmann, A., Angombe, S., Kindermann, L., Linstädter, A., Mörchen, R. (2022). Conservation with elephants and agricultural intensification: effects on lignin and n-alkanes in soils of sub-Saharan Africa. Geoderma 425, 116009.

• Zhao, Y., Reichel, R., Herbst, M., Sun, Y., Brüggemann, N., Mörchen, R., Welp, G., Meng, F., Bol, R. (2022). Declining total carbon stocks in carbonate-containing agricultural soils over a 62-year recultivation chronosequence under humid conditions. Geoderma 425, 116060.

• Fuentes, B., Choque, A., Gómez, F., Alarcón, J., Castro-Nallar, E., Arenas, F., Contreras, D., Mörchen, R., Amelung, W., Knief, C., Moradi, G., Klumpp, E., Saavedra, C., Prietzel, J., Klysubun, W., Remonsellez, F., Bol, R. (2022). Influence of Physical-Chemical Soil Parameters on Microbiota Composition and Diversity in a Deep Hyperarid Core of the Atacama Desert. Frontiers in Microbiology 12, 794743.

• Orozco-Ortiz, J. M., Peña-Venegas, C.P., Bauke, S.L., Borgemeister, C., Mörchen, R., Lehndorff, E., Amelung, W. (2021). Terra Preta Properties in Northwestern Amazonia (Colombia). Sustainability 13, 7088.

• Di, W., Senbayram, M., Moradi, G., Mörchen, R., Knief, C., Klumpp, E., Jones, D.L., Well, R., Chen, R., Bol, R. (2021). Microbial potential for denitrification in the hyperarid Atacama Desert soil. Soil Biology and Biogeochemistry, 157, 108248.

• Mörchen, R., Amelung, W., Giese, C., Böhnert, T., Lehndorff, E. (2021). Fingerprints of plant life in the Atacama Desert – Insights from n-alkane analyses. Organic Geochemistry, 151, 104145.

• Moradi, G., Bol, R., Trbojevic, L., Missong, A., Mörchen R., Fuentes, B., May, S.M., Lehndorff, E., Klumpp, E. (2020). Contrasting depth distribution of colloid-associated phosphorus in the active and abandoned sections of an alluvial fan in a hyper-arid region of the Atacama Desert. Global and Planetary Change, 185, 103090.

• Knief, C., Bol, R., Amelung, W., Kusch, S., Frindte, K., Eckmeier, E., Jaeschke, A., Dunai, T., Fuentes, B., Mörchen, R., Schütte, T., Lücke, A., Klumpp, E., Kaiser, K., Rethemeyer, J. (2020). Tracing elevational changes in microbial life and organic carbon sources in soils oft he Atacama Desert. Global and Planetary Change, 184, 103078.

• Kusch, S., Jaeschke, A., Mörchen, R., Rethemeyer, J. (2020). Tracing life at the dry limit using phospholipid fatty acids – does sampling matter? Soil Biology and Biogeochemistry, 141, 107661.

• Mörchen, R., Lehndorff, E., Arenas Diaz, F., Moradi, G., Bol, R., Fuentes B., Klumpp, E., Amelung, W. (2019). Carbon accrual in the Atacama Desert. Global and Planetary Change, 181, 102993.

Teaching:

Soil resources of the world

Soil and Water Protection

Principles of Soil Science