| The lower Rhine floodplains play an important role as sinks ofsuspended sediments and pollutants, and have a key-role in ecologicaltransformation processes along the river continuum from the upstreambasin towards the estuary. Large-scale river measures for increasingthe discharge capacity of the rivers and ecological restoration,together with climate change are expected to lead to considerablechanges in the bio-geomorphological functioning of the floodplainsystem. The present project aims at quantification of theinteractions between sediment deposition and ecosystem functioning offloodplains, and at assessment of the impact of human interferenceand climate change on fine sediments transport and ecologicaltransformations in the lower Rhine delta over a time scale of acentury. Sub-project I will quantify the influence of floodplainvegetation on flow patterns and deposition of sediment and heavymetals using (1) airborne laser altimetry techniques, (2) fieldsampling of vegetations density, over bank flow characteristics andfloodplain sedimentation, and (3) modeling. Sub-project II analyses the hydro-morphological impacts of ecologicaltransformations in semi terrestrial food chains, thereby extendingthe "Flood Pulse" concept. Existing ecological models will be adoptedusing field data and mesocosm experiments, together withconcentrations and bio-availability of heavy metals. Sub-project IIIcombines the results in a conceptual model of floodplainsedimentation and changes in the floodplain food chains for theentire river reach Waal-Merwede. This model is used in sensitivityanalyses to assess the impacts of human interference and climatechange on sediment delivery and ecological transformation processes between the upstream river basin and the estuary |
