Since 2008, I am a senior researcher in the environmental physics group led by Niki Gruber. Within this group, my research focuses on marine ecosystem dynamics and functioning, both in modelled and observed marine ecosystems. Key research issue involve the verification of principles of marine ecology, and the quantification of changes in marine ecosystem structure and functioning due to environmental and climate change. In particular, I am interested in the stability of and changes in marine ecosystem composition, ecological niches and biogeochemical provinces under climate change. Furthermore, I am interested in species and plankton functional group distribution patterns in the global ocean, and the link between plankton biogeography and biodiversity and ecosystem service provision.


I am a member of the scientific steering committee of the MARine Ecosystem Inter-comparison Project (MAREMIP; pft.ees.hokudai.ac.jp). MAREMIP compares the representation of plankton functional types in different global lower trophic level marine ecosystem models. The project also promotes a more accurate representation of marine biology in current ocean biogeochemistry models and fosters collaboration between marine ecosystem modellers. It also aims to identify key issues for future model development and to answer important questions of current marine ecosystem research, such as the quantification of the vulnerability of lower trophic ecosystems to climate change and the impact of changes in marine ecosystem structure and functioning on global biogeochemical cycles. Within MAREMIP, I am interested in how ecological niches of PFTs are simulated in different models and how this compares to observational data from satellites, in the link between food web structure and functioning, the representation of bloom dynamics and its drivers, and the fate of organic matter produced and cycled in marine ecosystems.

I am also one of the co-coordinators of the MARine Ecosystem DATa project (MAREDAT - Towards a World atlas of marine plankton functional types; www.maredat.info), an international effort to collect and archive global plankton abundance and biomass data. The MAREDAT team has recently published a special issue in the journal Earth System Science Data (http://www.earth-syst-sci-data.net/special_issue9.html), and has brought together over 700'000 data points for plankton abundance, and over 400'000 biomass measurements for 10 plankton functional types (data can be downloaded from www.pagaea.de). The database also includes a global HPLC pigment data base with more than 40'000 pigment measurements. The database is useful for a diverse range of applications, from model development and validation to applications in marine ecology and biological oceanography, and also in ecogeography. We hope that the data will help us understand the distribution patterns of marine organisms, and clarify the respective roles of different organisms and plankton functional groups for global biogeochemical cycles, ecosystem functioning and ecosystem service provision.

Through the work of my collaborators, PhD students and MSc students, I am currently involved in projects on species distribution modelling and global plankton biogeography, the role of phytoplankton succession and competition for Southern Ocean nutrient dynamics, the determination of phytoplankton functional group distribution based on HPLC pigments, the relationships between plankton distribution and export patterns in model ecosystems, and the ecological niches and biodiversity patterns of haptophytes (coccolithophores) and diatoms, and the evaluation of phytoplankton biogeography in global marine ecosystem and climate models.