Fish assemblage changes relative to environmental factors and time in the Warta River, Poland, and its oxbow lakes

摘要: Four oxbow lakes and two neighbouring sections of their parent Warta River (Odra system, Poland) were sampled to investigate differences in fish assemblages between habitats 1999-2000. Additional comparisons made with 12 other this section the river that 30-40 years ago. Downstream a man-made reservoir, higher species number, diversity evenness recorded than channel. Upstream these variables from both insignificant. Fluvial stagnant water samples clearly separated multivariate space detrended correspondence analysis (DCA). For River, abiotic biotic environmental available, only velocity, temperature conductivity significantly correlated canonical (CCA) axes. Fish four recently investigated DCA oxbows Species previously subdominant becoming rare. Oxbow are continuously or at least periodically connected channel indispensable for maintaining high biodiversity sustainable fishery system.