Sampling a World Heritage with the SIRF grant

by Geo Nikolov, Class of 2014

I am a major of Earth Sciences with a Major Concentration on Geoscience and have just completed a full year of study at the University of Bremen. This summer, I was able to participate in a research project funded by Dickinson’s SIRF grant. Here, I will give a brief description of this project:


Marine Geochemical research is conducted by several prestigious institutes in Bremen and Bremerhaven, including The Max Planck Institute for Marine Microbiology, MARUM (Center for Marine Environmental Sciences), and the Alfred Wegener Institute for Polar- and Ocean Research.  The research group “The Ocean in the Earth System” at the MARUM institute at the  University of Bremen has been officially recognized as a “Cluster of Excellence” by the German Research Foundation and German Council of Science and Humanities.

This semester, I sought out a collaborative research opportunity with a marine geochemist to gain experience in sampling methods, data collection and data analysis within the framework of an environmentally relevant project that would provide the basis for a senior thesis in my major of Geoscience.

Professor Michael Schlüter, geochemist at the Alfred-Wegener-Institute for Polar- and Ocean Research, Bremerhaven, and teacher of the course “Geochemical cycles and processes,” offered me the chance to assist in a research project quantifying flow rates of Submarine Groundwater Discharge (SGD) and sampling pore water in the Sahlenburg intertidal mudflats near Cuxhaven, Germany. The sampling, data collection and transport modelling conducted in association with this project provided the basis for further analytical work to be completed for my senior thesis in 2013/2014. In addition, Marine Geochemistry is a field in which I am strongly considering pursuing a graduate degree.

Specific Tasks and Responsibilities

My responsibilities at the research site covered pore water sampling, data analysis, and transport modelling. Pore water sampling was conducted with rhizones and suction cups at the field site Sahlenburger Watt in the Lower Saxon Wadden Sea National Park, Germany. In the field, I also assisted with the determination of pressure surfaces and in-situ measurements of submarine groundwater discharge. Laboratory work centered on chemical analysis, specifically, the determination of nutrient pore water profiles. Chloride concentration data was used to model flow rates of submarine groundwater.

Connection to Dickinson Classes and Experiences

The Dickinson course “Chemistry of Earth Systems” introduced me to the foundations of marine sediment pore water chemistry, including an overview of transport processes and depth profiles of nutrients. At the University of Bremen, I have deepened my knowledge in the areas of pore water composition and early diagenesis through the geochemistry course “Element Cycles and Processes,” which included an overview of redox reactions, reaction kinetics and the use of tracers.

Environmental Relevance

The working area, the Sahlenburg intertidal mudflats, lies in the Lower Saxon Wadden Sea National Park, a UNESCO World Heritage Site since 2009. This nature reserve, covering an area of approximately 1.300 sq. mi, is home to over 4,000 plant and animal species. It is also a resting place for 10-12 million birds arriving every winter from Northern countries to prepare for breeding. Thus, the ecosystem’s productivity is essential to global biodiversity. The ecosystem is highly sensitive to fluxes of nutrients such as nitrate and phosphate, which are heavily supplied by fertilizer runoff. The OSPAR Commission for the Protection of the Marine Environment of the North-East Atlantic identified the German Bight and Wadden Sea as “Eutrophication Problem Areas” in 1994.

Submarine Groundwater Discharge can contribute a major fraction of nutrients to the water column; in some areas, as much as 70 percent of the total nitrate. This project, conducted over several weeks, with similar measurements to be repeated in the future, constitutes basic research that will better monitor nutrient fluxes stemming from an essential individual component of this fragile ecosystem’s water budget.

International Relevance

Submarine Groundwater Discharge is a topic in Marine Geochemistry that is of global geochemical relevance. SGD has only been quantified for small portions of the world’s coastlines, most investigations having taken place on the East coast of the United States, in the Mediterranean, in the Baltic Sea, in the North Sea, and on the coasts of Japan. Estimates of SGD as a component of the global water cycle are thus still somewhat unreliable.

This research experience represented the opportunity to learn directly from an expert, with whom I could communicate in German. International scientific cooperation will be necessary to more fully understand the global impact of this essential component of the hydrological cycle.


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