This work reports the results of an investigation of reservoirs that were selected in Hungary in the framework of a new flood control strategy for the River Tisza, the largest tributary of the River Danube. Through a comprehensive analysis the optimal operation mode was identified, which would need to be applied to achieve the maximum decreasing effect on peak water levels. The flood waves were simulated using a 1D hydrodynamical model, which is based on the Saint-Venant equations. Both measured and synthetic discharge data were used as boundary conditions. The time lead as compared to the flood peak was determined for the reservoir system. On the Upper-Tisza the figures exceed the order of magnitude of the possible time lead of the realistic forecast, meaning that further research of the reconditioned discharge forecast is necessary. The investigation results of the interaction of two reservoirs showed that the sum of the decreasing effects on water levels when separated reservoirs work independently approaches the decreasing effect of the jointly operating reservoirs reasonably well. Therefore the joint impacts can be estimated using quick linear programming methods.Keywords flood control · reservoir systems · 1D hydrodynamic model Acknowledgement This work is connected to the scientific program of the "Development of quality-oriented and harmonized R+D+I strategy and functional model at BME" project.
We examined the effluent from a municipal (Nyíregyháza, Hungary) wastewater treatment plant (WWTP) on hydrophysicochemical properties and on diversity, community structure, and stability of fish assemblages at the recipient low flow channel system during a two-year period. The WWTP outflow increased significantly the nutrient concentrations (e.g. NO2 and NO3 concentrations increased to 4x and 8x respectively), and the regime (with the permanent ~0.23m 3 /s load) at the recipient channel sections. The wastewater outflow not only altered, but stabilized the physico-chemical variables measured, and the water regime in the recipient channels. Thus the natural, periodic fluctuation of the environmental variables was diminished in the study period. The WWTP outflow caused significant changes in the fish fauna as well. High abundances and taxa richness were found in the stocks inhabiting the charged watercourse sections. At the same time, species composition and relative abundances of fish stocks proved to be more constant at the impaired sites. Our results show that the WWTP outflow caused altered, but significantly more stable environmental conditions. These alterations were favourable for the emergence of a more diverse and more stable fish community on the recipient channel sections. Hence, the dynamic variability in fish assemblage structure that is characteristic of natural lowland stream was not apparent in these perturbed, semi natural habitats.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.