Funktionalität von Potamalfischaufstiegshilfen im Marchfeldkanalsystem

This article describes studies undertaken to test the performance of diversion channels in lowland river sections, using abiotic and biotic characteristics. Critical passages in an installation facilitating the upstream migration of fish are usually the transitions between basins. Increased flow velocities (v) > 1 m/s have been seen to occur only at individual points, with a sufficient proportion of cross-sectional area remaining where v < 1 m/s, as can be demonstrated by the graph showing equivelocity contours. In 1993, 7500 fish of 28 species passed the two fish migration facilities studied. After adaption of the facilities, the rate increased to 60000 fish of 36 species in 1994. The suitability of the diversion channel for many small fish species and/or fry has been established