Identification of correlations between sediment and biology by comparing the conformity of hydromorphological results of a sediment management plan with assessments of biological quality elements (#257)
The Sediment Management Plan for the Elbe River (RBC Elbe 2013, ICPER 2014) combines the issues of sediment quantity, hydromorphology and sediment quality. Indicators for the assessment of the sediment status under the aspect of hydromorphology were selected relating to sediment management and the European Water Framework Directive (EC-WFD). Objectives were to investigate and evaluate the sediment budget as a part of the hydromorphological status of the river and to derive recommendations for actions to improve the conditions.
Representative indicators were analysed, e.g. sediment continuity, depth variation and substrate of the river bed. The hydromorphological results were compared with evaluations of the biological quality elements macrophytes, fishes, macroinvertebrates and phytoplankton by choosing different methods for aggregation on both examined subjects. The findings for biology were achieved in the context of the implementation of the EC-WFD by the German federal states.
Hydromorphological and biological quality components are closely linked. The intention of this study was to identify conformity between hydromorphological and biological status based on the size of their shares in same appraisals of results. This applies for finally averaged river stretches with a length of 5 km up to the water bodies of the inland Elbe River. The interactions were investigated for 585 km in total, the German federal waterway inland Elbe River extends from the German-Czech border to the Geesthacht weir.
In summary, the reached deliverables of the comparison provide various conclusions and may be suitable e.g. for integral sediment management, rehabilitation aspects and river basin management.