Prof. Dr. Kai Wirtz
News and Press Releases
- Unstable climate - bad luck for humanity Whether cultures flourished or declined over thousands of years depended on how much the climate changed. Major study links the history of human development with climate data.
- Do oceans absorb more CO2 than expected? New theory on the movement of phytoplankton could imply that oceans absorb more CO2 by 2100 instead of less.
- Greatest Migration on Earth Happens under Darkness Every Day Prof. Kai Wirtz explains vertical migration of marine phytoplankton
- Corona gets us tired Societies act rationally and in solidarity – but also increasingly experience a sense of fatigue, says a study of Helmholtz-Zentrum Hereon
My research is based on the idea that we can understand the dynamics of complex environmental systems such as coastal ecosystems through relatively simple regularities. The identification of such regularities using large data sets and newly developed modeling techniques still dominates my work today. Using these, often in realistic coupled physical-biological simulations, my team and I attempt to estimate the response of marine nearshore ecosystems to multiple changes from human uses and climate.
My research focuses on
- biological adaptation and its quantitative description (via "traits")
- planktonic organisms as the basis of the marine food web
- the interaction of ecology, biogeochemistry and physics on the seafloor
- the modeling of social processes and human-environment interaction
Education
| 2009 | Accredited manager degree of the Helmholtz-Akademie |
| 2005 | Habilitation, University of Oldenburg |
| 1998 | Doctoral degree, University of Kassel |
| 1994 | Diploma (Physics), University of Oldenburg |
Research Experience
| 2004 | Dept. Head at Institute of Coastal Research, Hereon Professor at the CAU Kiel |
| 2003–2004 | Head of Junior Reasearch Group IMPULSE at the ICBM Oldenburg |
| 1999–2002 | Postdoc at the Institute for Marine Chemistry and Biology (ICBM) Oldenburg |
| 1998–1999 | Research Assistant at the Terramare Wilhelmshaven |
| 1997 | Paternity leave |
| 1994–1996 | Centre for Environmental Research at the University of Kassel |
Funding (only most recent)
| 2016–2018 | BIOACID Synthesis (BMBF) |
| 2015–2018 | DYNATRAIT (Trait-based plankton modeling, DFG) |
| 2013–2019 | MOSSCO (Modular System for Shelves and Coasts, BMBF) Coordinator |
| 2020–2023 | MuSSeLS (Multiple Stressors on North Sea Life, BMBF) Coordinator |
Professional Activities and Memberships
| 2013 | Member of German coordination board for coastal research |
| 2009–2015 | Member of the the executive board of the coastal observatory COSYNA |
| 2008–2018 | Member of the Kiel Excellence Cluster Future Ocean |
| 2006–2019 | Head of the programmatic research in coastal ecology at Hereon |
since 2017
- Garcia-Oliva, O., Wirtz, K. (2024): Complex structure of aquatic food-webs emerges from few predator–prey constraints. Nature Ecology & Evolution.
- Stelzenmüller, V., Rehren, J., Örey, S., Lemmen, C., Krishna, S., Hasenbein, M., Püts, M., Probst, W.N., Diekmann, R., Scheffran, J., Bos, O.G., & Wirtz, K: (2024): Framing future trajectories of human activities in the German North Sea to inform cumulative effects assessments and marine spatial planning. Journal of Environmental Management, Vol. 349, 119507, doi:10.1016/j.jenvman.2023.119507
- Wirtz, K.W., Antunes, N., Diachenko, A., Laabs, J., Lemmen, C., Lohmann, G., McLaughlin, R., Zorita, E., & Gronenborn, D. (2024): Multicentennial cycles in continental demography synchronous with solar activity and climate stability. Nat Commun 15, 10248, doi:10.1038/s41467-024-54474-w
- Wirtz, K. W. (2024). Multicentennial cycles in continental demography synchronous with solar activity and climate stability (v1.1.0). Zenodo. doi:10.5281/zenodo.13748527 (Software)
- Wirtz, K., Smith, S.L., Mathis, M., & Taucher, J. (2022): Vertically migrating phytoplankton fuel high oceanic primary production. Nat. Clim. Chang. (2022), doi:10.1038/s41558-022-01430-5
- García-Oliva, O., Hantzsche, F.M., Boersma, M., & Wirtz, Kai (2022): Phytoplankton and particle size spectra indicate intense mixotrophic dinoflagellates grazing from summer to winter. Journal of Plankton Research, Vol. 44, Issue 2, 2022, pp 224–240, doi:10.1093/plankt/fbac013
- García-Oliva, O., & Wirtz, K. (2022): Size-dependent and -independent prey selection of dinoflagellates. Mar Biol 169, 122, doi:10.1007/s00227-022-04102-2
- Wirtz, K. (2021): Changing readiness to mitigate SARS-CoV-2 steered long-term epidemic and social trajectories. Sci Rep 11, 13919 (2021), doi:10.1038/s41598-021-93248-y
- Zhang, W., Neumann, A., Daewel, U., Wirtz, K., van Beusekom, J.E.E., Eisele, A., Ma, M., & Schrum, C. (2021): Quantifying importance of macrobenthos for benthic-pelagic coupling in a temperate coastal shelf sea. Journal of Geophysical Research: Oceans, 126, e2020JC016995, doi:10.1029/2020JC016995
- Gronenborn, D., Strien, H.-C., Wirtz, K.W., Turchin, P., Zielhofer, C., & van Dick, R. (2020): Inherent Collapse? Social Dynamics and External Forcing in Early Neolithic and Modern SW Germany.” In: Riede, F., & Sheets, P.D. (eds.): Going Forward by Looking Back: Archaeological Perspectives on Socio-Ecological Crisis, Response, and Collapse, 333-366, Catastrophes in Context volume 3, New York, Oxford: Berghahn.
- Wirtz, K., & Smith, S.L. (2020): Vertical migration by bulk phytoplankton sustains biodiversity and nutrient input to the surface ocean. Sci Rep 10, 1142, doi:10.1038/s41598-020-57890-2
- Xu, X., Lemmen, C., & Wirtz, K.W. (2020): Less Nutrients but More Phytoplankton: Long-Term Ecosystem Dynamics of the Southern North Sea. Front. Mar. Sci. 7:662, doi:10.3389/fmars.2020.00662
- Taherzadeh, N., Bengfort, M., & Wirtz, K.W. (2019): A Trait-Based Framework for Explaining Non-additive Effects of Multiple Stressors on Plankton Communities. Front. Mar. Sci. 6:351, doi:10.3389/fmars.2019.00351
- Zhang, W., Wirtz, K., Daewel, U., Wrede, A., Kröncke, I., Kuhn, G., Neumann, A., Meyer, J., Ma, M., & Schrum, C. (2019): The budget of macrobenthic reworked organic carbon - a modelling case study of the North Sea. Journal of Geophysical Research-Biogeosciences, doi:10.1029/2019JG005109
- Wirtz, K.W. (2019): Physics or biology? Persistent chlorophyll accumulation in a shallow coastal sea explained by pathogens and carnivorous grazing. PLOS ONE, February 22, doi:10.1371/journal.pone.0212143
- Chen, B., Smith, S.L., & Wirtz, K.W. (2019): Effect of phytoplankton size diversity on primary productivity in the North Pacific: trait distributions under environmental variability. Ecol Lett, 22: 56-66, doi:10.1111/ele.13167
- Ingrid Holzwarth, Holger Weilbeer and Kai W. Wirtz (2019): The effect of bathymetric modification on water age in the Elbe Estuary Die Küste, 87, https://doi.org/10.18171/1.087109
- Schartau, M., Riethmüller, R., Flöser, G., Beusekom, J.E.E. van, Krasemann, H., Hofmeister, R., & Wirtz, K. (2019): On the separation between inorganic and organic fractions of suspended matter in a marine coastal environment. Progress in Oceanography, Volume 171, Pages 231-250, doi:10.1016/j.pocean.2018.12.011
- Zhao, C., Maerz J., Hofmeister, R., Röttgers, R., Wirtz, K., Riethmüller, R., & Schrum, C. (2019): Characterizing the vertical distribution of chlorophyll a in the German Bight. Continental Shelf Research, pp 127-146, doi:10.1016/j.csr.2019.01.012
- Michels, J., Stippkugel, A., Lenz, M., Wirtz, K., & Engel, A. (2018): Rapid aggregation of biofilm-covered microplastics with marine biogenic particles. Proc. R. Soc. B 20181203, doi:10.1098/rspb.2018.1203
- Slavik, K., Lemmen, C., Zhang, W., Kerimoglu, O., Klingbeil, K., & Wirtz, K.W. (2018): The large scale impact of offshore windfarm structures on pelagic primary production in the southern North Sea. Hydrobiologia, pp 1–19, doi:10.1007/s10750-018-3653-5
- Lemmen, C., Hofmeister, R., Klingbeil, K., Nasermoaddeli, M.H., Kerimoglu, O., Burchard, H., Kösters, F., & Wirtz, K.W. (2018): Modular System for Shelves and Coasts (MOSSCO v1.0) – a flexible and multi-component framework for coupled coastal ocean ecosystem modelling. Geosci. Model Dev., 11, 915-935, doi:10.5194/gmd-11-915-2018
- M.H. Nasermoaddeli, C. Lemmen, G. Stigge, O. Kerimoglu, H. Burchard, K. Klingbeil, R. Hofmeister, M. Kreus, K.W. Wirtz, F. Kösters (2017): A model study on the large-scale effect of macrofauna on the suspended sediment concentration in a shallow shelf sea. Estuarine, Coastal and Shelf Science, 2017, ISSN 0272-7714, doi:10.1016/j.ecss.2017.11.002
- Kerimoglu, O., Hofmeister, R., Maerz, J., Riethmüller, R., and Wirtz, K. W.: The acclimative biogeochemical model of the southern North Sea. Biogeosciences, 14, 4499-4531, doi:10.5194/bg-14-4499-2017
- Holzwarth, I., & Wirtz, K.W. (2017): Anthropogenic impacts on estuarine oxygen dynamics: a model based evaluation. Estuarine, Coastal and Shelf Science, doi:10.1016/j.ecss.2018.01.020
- Zhang, W., & Wirtz K.W. (2017): Mutual Dependence Between Sedimentary Organic Carbon and Infaunal Macrobenthos Resolved by Mechanistic Modeling. Journal of Geophysical Research: Biogeosciences, doi:10.1002/2017JG00390
2015-2016
- Moreno de Castro, M., Schartau, M. and Wirtz, K.W. (2016): Potential sources of variability in ocean acidification mesocosm experiments. Biogeosciences
- Wirtz, K.W. and Kerimoglu, O. (2016): Autotrophic Stoichiometry Emerging from Optimality and Variable Co-limitation. Frontiers in Ecology and Evolution, 4:131.
- Mandal, S., Homma, H., Priyadarshi, A., Burchard, H., Smith, S.L., Wirtz, K.W., Yamazaki, H. (2016): A 1D physical–biological model of the impact of highly intermittent phytoplankton distributions. J Plankton Res 2016; 38 (4): 964-976.
- Baschek, B., Schroeder, F., Brix, H., Riethmüller, R., Badewien, T. H., Breitbach, G., Brügge, B., Colijn, F., Doerffer, R., Eschenbach, C., Friedrich, J., Fischer, P., Garthe, S., Horstmann, J., Krasemann, H., Metfies, K., Ohle, N., Petersen, W., Pröfrock, D., Röttgers, R., Schlüter, M., Schulz, J., Schulz-Stellenfleth, J., Stanev, E., Winter, C., Wirtz, K., Wollschläger, J., Zielinski, O. and Ziemer, F. (2016): The Coastal Observing System for Northern and Arctic Seas (COSYNA). Ocean Science Discussions, pp. 1-73 .
- Su, J., Tian, T., Krasemann, H., Schartau, M., Wirtz, K.W. (2015): Response patterns of phytoplankton growth to variations in resuspension in the German Bight revealed by daily MERIS data in 2003 and 2004. Oceanologia Volume 57, Issue 4, October–December 2015, Pages 328–341.
2014
2012-2013
2010-2011
2008-2009
2005-2007