My research interests lie primarily in the study of hydrogeologic processes in porous coastal aquifers. In doing so, I use both field and computational numerical modeling methods (MODFLOW, MT3DMS, SEAWAT, PHREEQC, PHT3D, iMOD-WQ) to improve the understanding of groundwater flow and transport as well as hydrobiogeochemistry. My previous research work includes:
- Investigation of the impact of climate change and anthropogenic activities on the groundwater situation in coastal groundwater systems
- Paleo-reconstruction of historical salt distributions in coastal groundwater systems
- Investigation of hydrogeochemical processes in sandy beach and marsh sediments at the land/sea transition zone
- Investigation of hydrogeochemical processes in freshwater lenses below barrier islands
Curriculum vitae
Since 08/2021: Research Associate in the DFG project “DynaDeep", AG Hydrogeologie und Landschaftswasserhaushalt, Carl von Ossietzky Universität Oldenburg
06/2020 - 07/2021: Research Associate in the BMBF project “WAKOS”, AG Hydrogeologie und Landschaftswasserhaushalt, Carl von Ossietzky Universität Oldenburg
03/2019 - 05/2020: Research Associate in the DFG project “SALTSA”, AG Hydrogeologie und Landschaftswasserhaushalt, Carl von Ossietzky Universität Oldenburg
07/2019: P.h.D. (Dr. rer. nat.), Topic of thesis: "Hydrogeochemical Processes in a Barrier Island Aquifer (Spiekeroog, Northwest Germany)"
04/2018 - 06/2018: Research visit, CSIRO Land and Water, Perth, Australia
09/2015 - 02/2019: Research Associate in the DFG project “Ostplate”, AG Hydrogeologie und Landschaftswasserhaushalt, Carl von Ossietzky Universität Oldenburg
09/2013 - 08/2015: M.Sc. Environmental Engineering, Denmarks Technical University (DTU), Kongens Lyngby, Denmark, Topic of thesis: "Assessing the driving forces of trichloroethylene transport in a glacial-disturbed limestone aquifer"
12/2012 - 05/2013: Industrial Trainee, CSIRO Land and Water, Adelaide, Australia
01/2012 - 06/2012: Exchange semester, Södertörns Högskola, Huddinge, Sweden
10/2009 - 02/2013: B.Sc. Environmental Sciences, Carl von Ossietzky Universität Oldenburg, Topic of thesis: "Characterization and mapping of the freshwater-saltwater interface below the western part of Spiekeroog by means of stable isotopes and hydrochemical methods"
Publications
Peer-reviewed:
Seibert, S. L., Massmann, G., Meyer, R., Post, V. E. A. and Greskowiak, J., 2024. Reactive transport modeling to reveal the impacts of beach morphodynamics, storm floods and seasonal groundwater recharge on the biogeochemistry of sandy subterranean estuaries. Advances in Water Resources, p.104884. https://doi.org/10.1016/j.advwatres.2024.104884
Reckhardt, A., Meyer, R., Seibert, S. L., Greskowiak, J., Roberts, M., Brick, S., Abarike, G., Amoako, K., Waska, H., Schwalfenberg, K., Schmiedinger, I., Wurl, O., Böttcher, M. E., Massmann, G., Pahnke, K., 2024. Spatial and temporal dynamics of groundwater biogeochemistry in the deep subsurface of a high-energy beach. Marine Chemistry, 267, p.104461. https://doi.org/10.1016/j.marchem.2024.104461
Seibert, S. L., Greskowiak, J., Oude Essink, G. H. P., Massmann, G., 2024. Understanding climate change and anthropogenic impacts on the salinization of low-lying coastal groundwater systems. Earth's Future, 12, e2024EF004737. https://doi.org/10.1029/2024EF004737
Seibert, S. L., Massmann, G., Meyer, R., Post, V. E. A., Greskowiak, J., 2024. Impact of mineral reactions and surface complexation on the transport of dissolved species in a subterranean estuary: Application of a comprehensive reactive transport modeling approach. Advances in Water Resources, 104763. https://doi.org/10.1016/j.advwatres.2024.104763
Greskowiak, J., Seibert, S.L., Post, V.E.A., Massmann, G., 2023. Redox-zoning in high-energy subterranean estuaries as a function of storm floods, temperatures, seasonal groundwater recharge and morphodynamics. Estuarine, Coastal and Shelf Science, 290, p.108418. https://doi.org/10.1016/j.ecss.2023.108418
Massmann, G., Abarike, G., Amoako, K., Auer, F., Badewien, T., Berkenbrink, C., Böttcher, M.E., Brick, S., Medina Cordova, I.V., Cueto, J., Dittmar, T., Engelen, B., Freund, H. Greskowiak, J., Günther, T., Herbst, G., Holtappels, M., Marchant, H., Meyer, R., Müller-Petke, M., Niggemann, J., Pahnke, K., Pommerin, D., Post, V., Reckhardt, A., Roberts, M., Schwalfenberg, K., Seibert, S.L., Siebert, C., Skibbe, N., Waska, H., Winter, C., Zielinski, O., 2023. The DynaDeep observatory – a unique approach to study high-energy subterranean estuaries. Frontiers in Marine Science, 10, p.1189281. https://doi.org/10.3389/fmars.2023.1189281
Karrasch, L., Siebenhüner, B., Seibert, S.L., 2023. Groundwater salinization in northwestern Germany: A case of anticipatory governance in the field of climate adaptation?. Earth System Governance, 17, p.100179. https://doi.org/10.1016/j.esg.2023.100179
Seibert, S.L., Greskowiak, J., Bungenstock, F., Freund, H., Karle, M., Meyer, R., Oude Essink, G.H.P., Van Engelen, J., Massmann, G., 2023. Paleo-Hydrogeological Modeling to Understand Present-Day Groundwater Salinities in a Low-Lying Coastal Groundwater System (Northwestern Germany). Water Resources Research, 59(4). https://doi.org/10.1029/2022WR033151
Waska, H., Simon, H., Ahmerkamp, S., Greskowiak, J., Ahrens, J., Seibert, S.L., Schwalfenberg, K., Zielinski, O., Dittmar, T., 2021. Molecular Traits of Dissolved Organic Matter in the Subterranean Estuary of a High-Energy Beach: Indications of Sources and Sinks. Frontiers in Marine Science8, 54. https://doi.org/10.3389/fmars.2021.607083
Seibert, S.L., Böttcher, M.E., Waska, H., Holt, T., Pollmann, T., Greskowiak, J., Massmann, G, 2021. Hydrogeochemistry of near-surface groundwater on a developing barrier island (Spiekeroog, Germany): The role of inundation, season and vegetation. Journal of Hydrology597, 126139. https://doi.org/10.1016/j.jhydrol.2021.126139
Reckhardt, A., Seibert, S.L., Holt, T., Ahrens, J., Beck, M., Massmann, G., Brumsack, H.J., 2021. Cycling of redox-sensitive trace metals in barrier island freshwater lenses. Science of The Total Environment768, 144964. https://doi.org/10.1016/j.scitotenv.2021.144964
Seibert, S.L., Degenhardt, J., Ahrens, J., Reckhardt, A., Schwalfenberg, K., Waska, H., 2020. Investigating the Land-Sea Transition Zone. In: Jungblut, S., Liebich, V., Bode-Dalby, M. (eds) YOUMARES 9 - The Oceans: Our Research, Our Future. Springer, Cham. https://doi.org/10.1007/978-3-030-20389-4_12
Seibert, S.L., Greskowiak, J., Prommer, H., Böttcher, M.E., Massmann, G, 2019. Modeling of biogeochemical processes in a barrier island freshwater lens (Spiekeroog, Germany). Journal of Hydrology 575, 1133-1144. https://doi.org/10.1016/j.jhydrol.2019.05.094
Holt, T., Greskowiak, J., Seibert, S.L., Massmann, G, 2019. Modeling the evolution of a freshwater lens under highly dynamic conditions on a currently developing barrier island. Geofluids, open-access article ID 9484657. https://doi.org/10.1155/2019/9484657
Seibert, S.L., Böttcher, M.E., Schubert, F., Pollmann, T., Giani, L., Tsukamoto, S., Frechen, M., Freund, H., Waska, H., Simon, H., Holt, T., Greskowiak, J., Massmann, G., 2019. Iron sulfide formation in young and rapidly-deposited permeable sands at the land-sea transition zone. Science of the total environment649, 264-283. https://doi.org/10.1016/j.scitotenv.2018.08.278
Seibert, S.L., Holt, T., Reckhardt, A., Ahrens, J., Beck, M., Pollmann, T., Giani, L., Waska, H., Böttcher, M.E., Greskowiak, J., Massmann, G., 2018. Hydrochemical evolution of a freshwater lens below a barrier island (Spiekeroog, Germany): The role of carbonate mineral reactions, cation exchange and redox processes. Applied Geochemistry92, 196-208. https://doi.org/10.1016/j.apgeochem.2018.03.001
Holt, T., Seibert, S.L., Greskowiak, J., Freund, H., Massmann, G., 2017. Impact of storm tides and inundation frequency on water table salinity and vegetation on a juvenile barrier island. Journal of Hydrology554, 666-679. https://doi.org/10.1016/j.jhydrol.2017.09.014
