| Shallow lakes are widespread, both in the Netherlands and in other regions. In the Netherlands, these lakes are often linked to the large drainage systems and water levels are managed in a strict way, leaving little room for a natural shore line to develop. Eutrophication and morphological pressures are therefore often occurring in a combined manner, limiting the use of simple 1 to 1 dose-response relationships for prediction purposes. The quantification of effects of measures to improve the ecological status of such a water system requires therefore an integrated assessment of all aspects, involving many disciplines ranging from hydrology to ecology. Often deterministic modelling tools are used to carry out system analyses and effects of measures,that consist of both hydrodynamic flow and water quality modules. In this project SOBEK and Delft3D are used together with the water quality process library Delwaq, in which ecological feedback mechanisms to flow and morphology are currently only available in a rather limited way. Objectives: To develop a better description of interactions between biota and abiotic processes in shallow lakes, and to implement these in existing modelling tools, improving them for more appropriate fday to day water management. Both full lake functioning and more detailed understanding of specific ecohydromorphological processes at different scale levels are distinguished within the study. Macrophytes and filter feeders (freshwater bivalves) are the main focus per scale level. Various experimental studies and field-work are combined with deterministic modelling and specific data for model calibration and validation will be gathered. |
