Limnophysics and Lake Modelling
head: Dr. Bertram Boehrer
ph.: +49 391 - 810 9441
fax: +49 391 - 810 9150
D - 39114 Magdeburg
Physical Limnology deals with stratification and tranport processes in lakes. We apply theoretical approaches, field investigations and numerical models for conclusions about stratification, currents, matter transport and evolution of water quality. We moved reservoirs into the focus without giving uo our experiences in natural lakes and pit lakes.
As a consequence of restricted vertical exchange, gradients - e.g. of dissolved oxygen - can form in lakes. These gradients may exist for limited periods like a summer stratification or may persist perennially (meromixis). Further chemical changes and consequences for the organism community are the result. We investigate how reservoirs can be managed to optimize their use while undesirable evolutions for water suppliers and leisure use are avoided to eventually implement a sustainable management of water resources of a healthy aquatic environment.
Compared to seas, lakes show a high variability. Marine standards do not satify today's requirements of accutracy. We are searching approaches that include differences between lakes appropriately and we try to develop models for the numerical implementation. This includes exchange of water, energy, and matter, as well as internal waves, mixing processes, turbulent transport coefficients and recently more accurate calculation of density of lake water. Beyond this, also special topics like thermobaric stratification and supersaturated deep waters find their space in our work group.
For our investigations, we used field measurements (meteorological measurements above water, multiparameter probes, current meters and deployable sensors for logging water properties). Numerical models in current use are: GLM, DYRESM, DELTARES, ELCOM. For more details, see projects.
From the expertise with mining lakes, the focus is on transport in highly stratified deep water, as can be found in permanently stratified water bodies such as meromictic lakes.
Observational data of stratification in and the meteorology above several mining lakes in Central Germany and Lusatia have been acquired for periods of several years, documenting the development during flooding of voids or remediation treatment of the lake. Scientific contributions have been published on the long-term prognostibility of meromixis, the interconnection of internal waves, currents and vertical mixing in deep stratified waters, density measurements avoiding or dealing with the problems of chemical stratification, and exchange flows between basins of a structured lake.
Technical support for GIS (global information system), DGPS (differential global positioning system) and mapping facilities, as well as the technical requirements for the data bank of physical, chemical and biological data are provided by the physical limnology.
Links to more groups on physics topics within UFZ in Magdeburg
modelling of rivers: Department Aquatic Ecosystems Analysis and Management Olaf Büttner
Measurements in rivers and streams: Department Aquatic Ecosystems Analysis and Management Uwe Kiwel
Relational Data Bank Systems Olaf Büttner and Margarete Tibke
Geographical Information Systems Olaf Büttner und Burkhard Kuehn