12 research outputs found

    Factors governing macrozoobenthic assemblages in perennial springs in north-western Switzerland

    Get PDF
    Springs are important freshwater habitats that provide refuge for many rare species. In this study, the fauna and abiotic parameters of 20 perennial springs in north-western Switzerland were investigated. Correlation of abiotic and macrozoobenthos data showed that physicochemical parameters had little impact on macrozoobenthic composition, whereas specific substrate parameters strongly influenced the composition of the macrofauna. Surprisingly, nonmetric multidimensional scaling did not reveal a grouping of springs with similar substrate composition or macrozoobenthic assemblages. However, discharge was identified as the factor significantly determining substrate and the composition of macroinvertebrate assemblages. This justifies the hypothesis that, variation in discharge is the disturbance factor governing the macrofaunal composition temporally and spatially within and between patche

    Factors governing macrozoobenthic assemblages in perennial springs in north-western Switzerland

    No full text
    Fauna in 20 ausgewählten Quellen der Nordwestschweiz Springs are important freshwater habitats that provide refuge for many rare species. In this study, the fauna and abiotic parameters of 20 perennial springs in north-western Switzerland were investigated. Correlation of abiotic and macrozoobenthos data showed that physicochemical parameters had little impact on macrozoobenthic composition, whereas specific substrate parameters strongly influenced the composition of the macrofauna. Surprisingly, nonmetric multidimensional scaling did not reveal a grouping of springs with similar substrate composition or macrozoobenthic assemblages. However, discharge was identified as the factor significantly determining substrate and the composition of macroinvertebrate assemblages. This justifies the hypothesis that, variation in discharge is the disturbance factor governing the macrofaunal composition temporally and spatially within and between patches

    A decision support procedure for integrative management of dammed raw water reservoirs

    Full text link
    Dammed drinking water reservoirs with their catchment areas and the downstream rivers are dynamic systems that change permanently under the influence of many factors. Their multifunctional use for drinking water supply, flood control, energy production, nature conservation and recreation as well as ecological constraints for the rivers downstream requires an integrative management considering and balancing between different requirements. Thus, an optimal reservoir management has to take into account scenarios of external influences and must be based on predictions of prospective raw water qualities. Furthermore, the impacts of short- and long-term changes of the raw water quality on drinking water treatment have to be considered. The problem is very complex and cannot be solved intuitively but requires the application of hydrological, ecological and process models. This approach was followed in the work presented here, as a tool to predict and evaluate the impacts of different reservoir management strategies in an integrative way is currently not available. The developed decision support procedure (DSP) allows for the estimation of the effects of different hydrological and water quantity management scenarios on raw water quality, water processing costs and ecology in the downstream river. Extreme hydrological events or changing boundary conditions (e.g. climate change) are taken into account.</jats:p
    corecore