Author(s): C. Hauer; G. Unfer; H. Habersack
Linked Author(s): Christoph Hauer
Keywords: No Keywords
Abstract: So far bioenergetic processes and drift feeding strategies are only sparely included into numerical habitat analysis. The significance of drifting invertebrates to stream fish lies in an increase in the availability of food. Within the presented paper a new suitability parameter for drift feeding SIF was derived using relationships of sources and sinks for benthic drift based on bottom shear stress (Nm-2) of depth-averaged two-dimensional numerical modeling. The new concept was matched to habitat evaluation (WUAs) of River2D©using velocity/depth suitability as modeling parameters. The comparison between the two modeling approaches highlighted a shift of preferred habitats of drift feeding fish from the pool tail to the middle and/or head of pools (+13.51 m/+14.19 m in upstream direction). The presented concept should allow evaluating habitats of drift feeding fish and/or the impact on habitats on various scales (macro-, meso-and micro scale), depending on numerical dimension (1D, 2D or even 3D modeling). Due to the aims of the European Water Framework Directive (EWFD) this approach might be used for evaluating sources and sinks in the food web combined with determining habitat suitability.
Year: 2009