Author(s): Volker Spork; Jurgen Kongeter
Linked Author(s): Jürgen Köngeter, Volker Spork
Keywords: No Keywords
Abstract: Morphological processes in low land rivers are dominated by transport phenomena of fine and cohesive sediments. A great number of experi-ments dealt with the behavior of abiotic sediments. It is known that by biotic activity a significant modification of the sediment stability and the flocculation processes in suspension can be achieved. The influences vary with different organisms. Stabilization can be caused by agglutination of particles or covering the surface and filling inter-particle voids with secre-tion of micro-organisms. The Institute of Hydraulic Engineering and Wa-ter Resources Management (IWW) at Aachen University of Technology carried out experiments to get information about the biogenic stabiliza-tion of fine grained sediments by a diatom film. The used species navicula pelliculosa and nitzschia palea are representative algae in German rivers and reservoirs. Erosion experiments in a small erosion unit, in which the water is driven by a propeller, showed a significant stabilization of an arti-ficial sediment (caolinite) by the diatomfilm. The magnitude of stabiliza-tion is strongly dependent on the growth period and assemblage of micro-bial organisms.
Year: 1997