Classification of the Oxbow Lakes of the Hármas-Körös River and Determination of Ways for Further Exploiting the Various Water Regions in the Light of the Water Framework Directive

Abstract

Hármas-Koros river lies between the mouth of the Tisza and the city Békés. In the nineteenth century, the work of regulatory her bed was made, which resulted in 44 oxbow lakes were created, of which 36 still exist till today. In presented work 14 oxbow lakes was selected and the following objectives were carried out: 1. The classification of oxbow lakes based on selected criteria: the manner and intensity of water exchange, sediment thickness, redox potential, usage, ichtiofouna. 2. The assessment of the state of spawning and its impact on ichtiofauna. 3. Determination the best methods of water management in particular types of oxbow lakes, which could stop their further degradation. The obtained results led to the following conclusions: - Tested oxbow lakes belong to different categories - Anthropogenic factors had a negative effect on the conditions of fish reproduction and survival of their juvenile stages. - The management of fisheries was not a factor differentiating the individual water regions, but had an impact on the ecological status. - For the maintenance and/or improvement of the natural environment of the individual oxbow lakes significant impact may have fishery management, carried out in the following years.