Wie viel „BIO“ braucht die Ökohydraulik? – Neue Ansätze und Modellentwicklungen für die integrative Wasserwirtschaft

The modeling of aquatic habitats is becoming increasingly important due to the various targets at the European and therefore also at the national scale. In addition to the requirements of the Water Framework Directive and the goals for the expansion of renewable energy sources, including hydropower, it is also the new strategies for biodiversity and the RED III regulation that make an integrative view of the use and rehabilitation of river systems absolutely necessary. The aim of this work is to present new approaches for the integrative modelling of instream habitats for different aspects of hydropower use. The results of the numerical models show that ecological optimization and assessment of the ecological impacts are possible for both, (i) questions of sediment management for impounded sections of small hydropower plants and (ii) for flushing of fine sediments in general. Furthermore, new habitat assessment methods provide the novel possibility to quantitatively assess the effects of river engineering measures in relation to hydropeaking. Although these predictive models are becoming increasingly sophisticated representing more and more processes, the overall discussion shows that basic research is still required in the field as well as on experimental basis in order to provide the integrative modelling approaches with the correct biological information.