My research interests are mainly focused on environmental science, paleoecology and limnology. Diatoms and ostracods from limnic systems are used as bioindicators for environmental assessment and reconstruction.
Dr. rer. nat., Technische Universität Braunschweig
PhD thesis title “Tracking Middle Pleistocene and Late Holocene environmental variability with aquatic microfossils examples from temperate and tropical climates” (Advisors Prof. Dr. Antje Schwalb, Prof. Dr. Brigitte Urban, Fund DFG project 350769604).
2014
Master in Environmental Science (M.Sc. Geoökologie), TU Braunschweig.
Master thesis title "Rekonstruktion der Umweltveränderungen des Kaschmir-Tals im Zeitraum der letzten 5000 Jahre mittels einer Diatomeenanalyse aus dem Manasbal See, Indien", Institute of Geosystems und Bioindication.
2011
Bachelor in Environmental Science (B.Sc. Geoökologie), TU Braunschweig.
Bachelor thesis title "Ursachen für die Auflösung von Diatomeenschalen im Sediment am Beispiel ihrer Erhaltung in Sedimentkernen des Tibet-Plateaus", Institute of Geosystems und Bioindication
Publications in international journals with peer review
Urban, B., Kasper, T., Krahn, K.J., van Kolfshoten, T., Rech, B., Holzheu, M., Tucci, M., Schwalb, A. (accepted). Landscape dynamics and chronological refinement of the Middle Pleistocene Reinsdorf Sequence of Schöningen, NW Germany. Quaternary Research. DOI: 10.1017/qua.2022.65
Neugebauer, I., Dinies, M., Plessen, B., Dräger, N., Brauer, A., Brückner, H., Frenzel, P., Gleixner, G., Hoelzmann, P., Krahn, K.J., Pint, A., Schwab, V.F., Schwarz, A., Tjallingii, R., Engel, M. (2022). The unexpectedly short Holocene Humid Period in Northern Arabia. Communications Earth and Environment, 3 (1), art. no. 47. DOI: 10.1038/s43247-022-00368-y
Wojewódka-Przybył, M., Krahn, K.J., Hamerlík, L., Macario-González, L., Cohuo, S., Charqueño, N., Cisneros, A., Hoelzmann, P., Yang, H., Rose, N., Zawisza, E., Pérez, L. & Schwalb, A. (2022). Imprints of the Little Ice Age and the severe earthquake of AD 2001 on the aquatic ecosystem of a tropical maar lake in El Salvador. The Holocene. 095968362211069. 10.1177/09596836221106965.
Neugebauer, I., Dinies, M., Plessen, B., Dräger, N., Brauer, A., Brückner, H., Frenzel, P., Gleixner, G., Hoelzmann, P., Krahn, K.J., Pint, A., Schwab, V.F., Schwarz, A., Tjallingii, R. & Engel, M. (2022). The unexpectedly short Holocene Humid Period in Northern Arabia. Communications Earth and Environment 3 (1), art. no. 47.
Reinhardt, A.L., Kasper, T., Lochner, M., Bliedtner, M., Krahn, K.J., Haberzettl, T., Shumilovskikh, L., Rahobisoa, J.-J., Zech, R., Favier, C., Behling, H., Bremond, L., Daut, G. & Montade, V. (2022). Rain Forest Fragmentation and Environmental Dynamics on Nosy Be Island (NW Madagascar) at 1300 cal BP Is Attributable to Intensified Human Impact. Frontiers in Ecology and Evolution 9, art. no. 783770.
Krahn, K.J., Tucci, M., Urban, B., Pilgrim, J., Frenzel, P., Soulié-Märsche, I. & Schwalb, A. (2021). Aquatic and terrestrial proxy evidence for Middle Pleistocene palaeolake and lake-shore development at two Lower Palaeolithic sites of Schöningen, Germany. Boreas 50 (3), 723-745.
Tucci, M., Krahn, K.J., Richter, D., van Kolfschoten, T., Álvarez, B.R., Verheijen, I., Serangeli, J., Lehmann, J., Degering, D., Schwalb, A. & Urban, B. (2021). Evidence for the age and timing of environmental change associated with a Lower Palaeolithic site within the Middle Pleistocene Reinsdorf sequence of the Schöningen coal mine, Germany. Palaeogeography, Palaeoclimatology, Palaeoecology 569, art. no. 110309.
Krahn, K.J., Schwarz, A., Wetzel, C.E., Cohuo-Durán, S., Daut, G., Macario-González, L., Pérez, L., Wang, J. & Schwalb, A. (2021). Three new needle-shaped Fragilaria species from Central America and the Tibetan Plateau. Phytotaxa 479 (1), 1-22.
Krahn, K.J., Wetzel, C.E., Ector, L. Schwalb, A. (2018). Achnanthidium neotropicum sp. nov., a new freshwater diatom from Lake Apastepeque in El Salvador (Central America). Phytotaxa 382 (1), 89-101.
Schwarz, A., Turner, F., Lauterbach, S., Plessen, B., Krahn, K.J., Glodniok, S., Mischke, S., Stebich, M., Witt, R., Mingram, J., Schwalb, A. (2017). Mid- to late Holocene climate-driven regime shifts inferred from diatom, ostracod and stable isotope records from Lake Son Kol (Central Tian Shan, Kyrgyzstan). Quaternary Science Reviews 177, 340-356.
Book contributions
Höhnke, C., Krahn, K.J. & Haas, K. (2022). Zusammenspiel von Mensch und Umwelt in Bad Waldsee. Interdisziplinäre Forschung zu mittelalterlicher bis frühneuzeitlicher Stadt- und Klimaentwicklung und deren Auswirkungen auf Gewässer, in: Landschaft - Region - Identität: Winfried Schenk zum 65. Geburtstag: mit Beiträgen der Jahrestagung 2021 in Leinefelde-Worbis und Heilbad Heiligenstadt im Eichsfeld (Siedlungsforschung. Archäologie - Geschichte - Geographie, Bd. 39), S. 523-541.
Krahn, K.J., Schwalb, A. (2018). Was uns Millionen kleiner Schalen über das Klima und die Umwelt vergangener Zeiten verraten können. In: Terberger, T., Böhner, U., Hillgruber, F., Kotula, A. (Hrsg.). 300.000 Jahre Spitzentechnik. Der altsteinzeitliche Fundplatz Schöningen und die frühesten Speere der Menschheit. Archäologie in Deutschland. wbg Theiss in Wissenschaftliche Buchgesellschaft (WBG), S. 119-120.
Conference contributions
Krahn, K.J., Haas, K., Lemmes, C., Saeidi Ghavi Andam, S., Gigl, F., Hinderer, M., Hirbodian, S., Marinova, E., Nelle, O., Rösch, M., Rückert, P., Plessen, B., Wick, L., Schwalb, A. (2022). Intertwining sedimentary and historic archives from medieval to early modern times: the story of Bad Waldsee (southern Germany). IAL IPA Joint Meeting 2022, Bariloche, Oral.
Krahn, K.J., Haas, K., Lemmes, C., Saeidi Ghavi Andam, S., Gigl, F., Hinderer, M., Hirbodian, S., Hollert, H., Marinova, E., Nelle, O., Rösch, M., Rückert, P., Plessen, B., Tjallingii, R., Wick, L., Schwalb, A. (2022). Multi-archive research for intertwined environmental and historic reconstruction of Bad Waldsee since medieval times. DEUQUA 2022, Potsdam, Poster.
Krahn, K.J., Pilgrim, J., Urban, B., Tucci, M. & Antje Schwalb, A. (2019). Middle Pleistocene interglacial environmental changes inferred from aquatic microfossils at the paleolithic site of Schöningen, Germany. INQUA 2019, Dublin, Poster.
Tucci, M., Krahn, K.J., Urban, B. & Schwalb, A. (2019). High-resolution sedimentological, pollen and aquatic microfossil analysis of Middle Pleistocene lakeshore deposits of paleolithic site Schöningen 13 II-4, Germany. INQUA 2019, Dublin.
Krahn, K.J., Daut, G., Rahobisoa, J.-J., & Schwalb, A. (2019). Diatom response to Holocene environmental change in NW Madagascar: first results from Lake Amparihibe. 12th Central European Diatom Meeting, Luxembourg, Poster.
Krahn, K.J., Wojewódka, M., Hamerlik, L., Macario-Gonzalez, L., Cohuo Duran, S., Hoelzmann, P., Rose, N.L., Yang, H., Zawisza, E., Pérez, L., Schwalb, A. (2018). Aquatic ecosystem response to late Holocene environmental variability recorded in Lake Apastepeque (central El Salvador). 25th International Diatom Symposium, Berlin, Germany. Poster
Krahn, K.J., Schwarz, A., Dinies, M., Plessen, B., Neugebauer, I., Frenzel, P., Pint, A., Hoelzmann, P., Engel, M. (2018). Diatoms in the Arabian Desert: Early to mid-Holocene paleolake development at the oasis of Tayma, NW Saudi Arabia. IPA-IAL 2018 Joint Meeting: Unravelling the Past and Future of Lakes, Stockholm, Sweden. Poster and short talk
Neugebauer, I., Dinies, M., Plessen, B., Dräger, N., Brauer, A., Frenzel, P., Gleixner, G., Hoelzmann, P., Krahn, K., Pint, A., Schwab, V.F., Schwarz, A., Tjallingii, R., Engel, M. (2018). The Early Holocene Humid Period in N Arabia - proxy evidence from a unique varved lake record. EGU General Assembly 2018, Vienna.
Krahn, K.J., Urban, B., Schwalb, A. (2017). Climate and environmental variability during the late Middle Pleistocene in Schöningen - New research approaches and prospects. Symposium: 25 years of Palaeolithic Research at Schöningen (Germany), Leiden, The Netherlands. Oral
Daut, G., Krahn, K.J., Rabhobisoa, J.-J., Moanazafy, S.O., Haberzettl, T., Kasper, T., Mäusbacher, R., Schwalb, A. (2017). How well suited are maar lakes of Madagascar for palaeoenvironmental multi-proxy reconstructions? - First results from shallow seismic, sedimentological and hydrological investigations in Central and Northwest Madagascar. EGU General Assembly, Vienna, Austria. Poster
Krahn, K.J., Schwarz, A. Dinies, M. (2016). Climate and environmental variability in northwestern Saudi Arabia during the early to mid-Holocene inferred from diatom analyses. 10th Central European Diatom Meeting, Budapest, Hungary. Oral
Schwarz, A., Dreßler, M., Krahn, K., Werner, P. (2016). Why is quality assurance in diatom analysis important? - Results of the 2nd German intercalibration exercise benthic diatoms. 10th Central European Diatom Meeting, Budapest, Hungary. Poster
Schwarz, A., Dressler, M., Krahn, K., Werner, P., Meybohm, A. (2015). 2. Ringversuch benthische Diatomeen 2014/15 in Deutschland - Beitrag zur Qualitätssicherung bei der Umsetzung der WRRL. 30. Jahrestagung der DGL, Essen, Deutschland. Oral
Schwarz, A., Krahn, K., Daut, G., Wang, J., Schwalb, A. (2015). Seasonal diatom succession in Lake Nam Co (Tibetan Plateau) inferred from sediment traps. 9th Central European Diatom Meeting, Bremerhaven, Germany. Poster
Krahn, K.J., Schwarz, A. Frenzel, P. & Schwalb, A. (2011). Preservation of diatom valves in sediment cores from the Tibetan Plateau. 5th International Limnogeological Congress, Konstanz, Germany. Poster
Krahn, K.J., Wojewódka, M., Hamerlik, L., Macario-Gonzalez, L., Cohuo Duran, S., Hoelzmann, P., Rose, N.L., Yang, H., Zawisza, E., Pérez, L., Schwalb, A. (2018). Aquatic ecosystem response to late Holocene environmental variability recorded in Lake Apastepeque (central El Salvador). 25th International Diatom Symposium, Berlin, Germany. Poster
Krahn, K.J., Schwarz, A., Dinies, M., Plessen, B., Neugebauer, I., Frenzel, P., Pint, A., Hoelzmann, P., Engel, M. (2018). Diatoms in the Arabian Desert: Early to mid-Holocene paleolake development at the oasis of Tayma, NW Saudi Arabia. IPA-IAL 2018 Joint Meeting: Unravelling the Past and Future of Lakes, Stockholm, Sweden. Poster and short talk
Neugebauer, I., Dinies, M., Plessen, B., Dräger, N., Brauer, A., Frenzel, P., Gleixner, G., Hoelzmann, P., Krahn, K., Pint, A., Schwab, V.F., Schwarz, A., Tjallingii, R., Engel, M. (2018). The Early Holocene Humid Period in N Arabia - proxy evidence from a unique varved lake record. EGU General Assembly 2018, Vienna.
Krahn, K.J., Urban, B., Schwalb, A. (2017). Climate and environmental variability during the late Middle Pleistocene in Schöningen - New research approaches and prospects. Symposium: 25 years of Palaeolithic Research at Schöningen (Germany), Leiden, The Netherlands. Oral
Daut, G., Krahn, K.J., Rabhobisoa, J.-J., Moanazafy, S.O., Haberzettl, T., Kasper, T., Mäusbacher, R., Schwalb, A. (2017). How well suited are maar lakes of Madagascar for palaeoenvironmental multi-proxy reconstructions? - First results from shallow seismic, sedimentological and hydrological investigations in Central and Northwest Madagascar. EGU General Assembly, Vienna, Austria. Poster
Krahn, K.J., Schwarz, A. Dinies, M. (2016). Climate and environmental variability in northwestern Saudi Arabia during the early to mid-Holocene inferred from diatom analyses. 10th Central European Diatom Meeting, Budapest, Hungary. Oral
Schwarz, A., Dreßler, M., Krahn, K., Werner, P. (2016). Why is quality assurance in diatom analysis important? - Results of the 2nd German intercalibration exercise benthic diatoms. 10th Central European Diatom Meeting, Budapest, Hungary. Poster
Schwarz, A., Dressler, M., Krahn, K., Werner, P., Meybohm, A. (2015). 2. Ringversuch benthische Diatomeen 2014/15 in Deutschland - Beitrag zur Qualitätssicherung bei der Umsetzung der WRRL. 30. Jahrestagung der DGL, Essen, Deutschland. Oral
Schwarz, A., Krahn, K., Daut, G., Wang, J., Schwalb, A. (2015). Seasonal diatom succession in Lake Nam Co (Tibetan Plateau) inferred from sediment traps. 9th Central European Diatom Meeting, Bremerhaven, Germany. Poster
Krahn, K.J., Schwarz, A. Frenzel, P. & Schwalb, A. (2011). Preservation of diatom valves in sediment cores from the Tibetan Plateau. 5th International Limnogeological Congress, Konstanz, Germany. Poster
Krahn, K.J., Pilgrim, J., Urban, B., Tucci, M. & Antje Schwalb, A. (2019). Middle Pleistocene interglacial environmental changes inferred from aquatic microfossils at the paleolithic site of Schöningen, Germany. INQUA 2019, Dublin, Poster.
Tucci, M., Krahn, K.J., Urban, B. & Schwalb, A. (2019). High-resolution sedimentological, pollen and aquatic microfossil analysis of Middle Pleistocene lakeshore deposits of paleolithic site Schöningen 13 II-4, Germany. INQUA 2019, Dublin, Poster.
Krahn, K.J., Daut, G., Rahobisoa, J.-J., & Schwalb, A. (2019). Diatom response to Holocene environmental change in NW Madagascar: first results from Lake Amparihibe. 12th Central European Diatom Meeting, Luxembourg, Poster.
Other publications
Wick, L., Haas, K., Krahn, K.J., Lemmes, C., Saeidi Ghavi Andam, S. (2022). Stadt - See - Umwelt: ein interdisziplinäres Forschungsprojekt zur mittelalterlich-frühneuzeitlichen Stadtentwicklung von Bad Waldsee, in: Kommission für geschichtliche Landeskunde Baden-Württemberg und dem Württembergischen Geschichts- und Altertumsverein (Hrsg.): Zeitschrift für Württembergische Landesgeschichte (= Bd. 81), Ostfildern 2022, S. 375-382.
Rupp, H., Turner, F., Laug, A., Naumann, K., Perez, L., Krahn, K., Börner, N., Schwarz, A., Veil, S., Schwalb, A. (2019). Zur Landschaftsgeschichte der Jeetzel-Niederung vom Ende der letzten Kaltzeit bis in die Gegenwart. Hannoversches Wendland, Band 19, 2016-2019, Lüchow, S. 7-36.
Jun. – Jul. 2016 and Aug. 2017 DAAD (German Academic Exchange Service) program: "PPP Program for Project Related Personal Exchange with Poland". Project title: “Aquatic ecosystem response to environmental changes recorded in late Pleistocene sediments from Lake Petén Itzá, Guatemala”. Polish Academy of Sciences, Instytut Nauk Geologicznych Polskiej Akademii Nauk, Warsaw, Poland.
WS2021/2022: Lecture: Bioindication and Analysis of Geoarchives. Master Program: Environmental Sciences and Environmental Engineering. Technische Universität Braunschweig. Shared lectures.
WS2021/2022: Seminar: Aquatic Biodiversity. Master Program: Environmental Sciences and Environmental Engineering. Technische Universität Braunschweig. Shared lectures.
WS2021/2022: Lecture: Climate Systems and Climate Variability, module: Climate Systems and Climate Variability. Master Program: Environmental Sciences. Technische Universität Braunschweig. Shared lectures.
WS2020/2021, WS2021/2022: Seminar: Climate change: Physical foundations, consequences, perspectives, module: Climate Systems and Climate Variability. Master program: Environmental Sciences. Technische Universität Braunschweig. Shared lectures.
WS2015/2016, WS2016/2017 Methods of sediment analysis, module: Aquatic Ecosystem. Bachelor program: Geoecology/Environmental Sciences, TU Braunschweig. Shared lectures.
Supervised theses
(2022) Malin Karkoska: Bryozoen als Bioindikatoren für die Umweltverhältnisse im oberschwäbischen Bad Waldsee vom Mittelalter bis in die frühe Neuzeit. Bachelor Program: Environmental Sciences. Institute of Geosystems and Bioindication. Technische Universität Braunschweig.
(2019) Sarah Teuber: Charophytes as environmental indicators in the Middle Pleistocene sediments of Schöningen. Bachelor Program: Environmental Sciences. Institute of Geosystems and Bioindication. Technische Universität Braunschweig.
(2019) Theresia Lauke: Ostracodes and gyrogonites as bioindicators for the reconstruction of the Paleo-environment in the Middle Pleistocene at the locations “12 II Deutsche Bahn-Pfeiler” in Schöningen. Master Program: Environmental Sciences. Institute of Geosystems and Bioindication. Technische Universität Braunschweig.
(2018) Julien Pilgrim: Ostracodes of the open-cast mine Schöningen (Profile Schöningen 13 II) and its implications for the interglacial paleoenvironment during the Middle Pleistocene. Master Program: Environmental Sciences. Institute of Geosystems and Bioindication. Technische Universität Braunschweig.
