"Mesohabitat Modelling with MesoCASiMiR: Mapping Method, Modelling "Habitat modelling as a beneficial tool for river management has become well established for many different ecohydraulic issues. The need for habitat models that are applicable over larger scales has led in recent years to the development of meso-scale habitat modelling approaches. MesoCASiMiR, developed at the Institute of Hydraulic Engineering at the University of Stuttgart, is one of the most developed modelling approaches aimed at the meso-scale. The main objectives of its development are to produce a) a highly efficient and impartial mapping methodology, b) a clear and convenient data evaluation and visualization tool based on GIS, and c) habitat simulations for certain scenarios (e.g. changed water allocations, mitigation measures, different intensities of water use) with particular consideration to specific meso-scale habitat needs, such as habitat connectivity and fragmentation. As a result, a decision support system is provided to water managers. The mappin!
g methodology and its evolution will be explained as well as the implementation of the fuzzy-logic based modelling approach of MesoCASiMiR. The applicability and value of such a decision support tool is presented via case studies and from the assessment of rivers (e.g. scenario based analysis) of different sizes and affected by a range of human impacts like inland navigation, hydropower and land use.