THE PROJECT

Sand extraction from the North Sea is expected to increase drastically for future infrastructure projects and coastal protection by sand nourishments. Large-scale marine sand extraction has important ecosystem effects, amongst others by changing the physical (e.g. turbulence and turbidity) and biogeochemical (e.g. nutrient availability) conditions that will propagate through the whole marine food web. Within the recently awarded project 'ORELSE' (Operational Recommendations for Ecosystem-based Large-scale Sand Extraction), a Dutch consortium will give recommendations for an ecosystem-based large-scale sand-extraction approach in the Dutch North Sea. 

The main approach of the NIOZ-led work package of the ‘ORELSE’ project, consisting of a PhD and a postdoc study, will be to translate laboratory-based experiments into novel mathematical descriptions for upscaling and predictions using physical-ecological coupled models. Phytoplankton (microscopic floating algae) is the basis of the marine food web and their abundance and production is controlled by physical conditions (e.g. light, turbidity and turbulence), nutrient availability and grazing. The main phytoplankton grazer is zooplankton, which constitutes an important trophic link between algae and fish. While good model descriptions for phytoplankton exist, current models of zooplankton growth and grazing behaviour typically assume no dependency on turbulence and turbidity, which probably does exist.  

The PhD-student will perform experiments in the laboratory on how zooplankton-phytoplankton (feeding) interactions depend on turbulence, silt concentration, and algal physiological conditions and will use the data to parameterise physiologically-based (DEB) model(s) of zooplankton dynamics. The new model descriptions will be applied in several idealized physical settings to predict how sand extraction, simulated by various nutrient conditions, hydrodynamic regimes, and turbidity, will affect phytoplankton and zooplankton dynamics.

The post-doc will use the model descriptions developed by the PhD-student, and cooperate with other partners in the project to set up and run scenarios for idealised and realistic sand-extraction pits (3-D) to investigate how sand extraction will affect the pelagic food web, both during the excavation phase (increased turbidity), and after establishment of the pits, via modified transport, turbulence and turbidity. The data will be used in a Digital Twin and Serious Game (developed by project partners) for adaptive temporal-spatial planning of ecosystem-based sand extractions to improve cross-sectoral collaboration and coordination between policymakers, the dredging industry, nature organisations, scientists and the fisheries sector in The Netherlands.

THE VACANCY

The PhD-project is at the interface of marine ecology and numerical modelling. On the one hand, you will setup and run laboratory experiments with phyto- and zooplankton, sort zooplankton under the microscope, work in the analytical laboratory and interpret results in the context of zooplankton dynamics. When possible, we will also encourage you to join expeditions with research vessels to the North Sea to gain field experience. On the other hand, you will translate the experimental results into mathematical descriptions and run numerical simulations. The PhD candidate will be based at EDS (Yerseke), but we foresee regular visits to COS (Texel) to facilitate the knowledge exchange with the post-doc and supervisors.

The PhD-candidate we are looking for, should have a MSc. degree in marine ecology and proven experience or affinity with numerical modelling. The candidate enjoys working in the laboratory, but also enjoys programming and numerical modelling. Given the interdisciplinary nature of the work, it is important that the PhD-candidate is open and communicative to facilitate interactions with other members of the group and the project consortium. Excellent English oral and writing skills are essential.

We highly encourage applicants from all members of our community and of diverse background, including LGBT+ and BAME communities, to join us.

Employment of this position at Royal NIOZ is by NWO-I (The Netherlands Organization of Scientific Research). The PhD position we are offering, will be based at the NIOZ-Yerseke. After a 12-month probationary period and successful evaluation, the position is extended for 36 months for a maximum employment of 4 years. The salary is compliant to the CAO-OI. Furthermore NIOZ offers a pension scheme, a holiday allowance of 8% of the gross annual salary, a year-end bonus of 8,3% of the gross annual salary, flexible work arrangements and 42 days of holiday leave (fulltime position). You may expect attractive secondary employment conditions. We offer generous relocation expenses for employees coming from abroad and support with finding accommodation.

Department of Estuarine and Delta Systems

The department of Estuarine and Delta Systems research (EDS, NIOZ-Yerseke) studies how the interplay between biota, hydrodynamics, sediment dynamics and biochemistry shapes the estuarine, deltaic and coastal environments in the context of natural and human-induced environmental changes. Central to our department is a multidisciplinary holistic approach that combines state-of-the-art biophysical, biochemical, ecological, physiological measurements, remote sensing, and manipulative experiments with mathematical and numerical modelling to create in-depth understanding of the processes that control estuarine and delta systems.

Royal NIOZ EDS is located in the village of Yerseke in the province of Zeeland and lies in the middle of the ‘Delta area’ on the southern border of the Eastern Scheldt. Yerseke offers a diverse but moderate level of facilities, including a thriving tourist industry, shops, sports facilities and primary schools. Within commuting distance you will find cities like Antwerp, Breda, Goes, Middelburg and Vlissingen.