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Analysis of erosion and runoff conditions in the Rozdrojovický stream watershed
Hegenbart, Vlastimil ; Pavlík, František (referee) ; Dumbrovský, Miroslav (advisor)
The subject of this bachelor thesis is to analyse the area with regard to erosion and runoff conditions and the transport of sediments into the Brno dam. The erosion calculation is carried out in two variants when the R-factor is changed. The USLE equations were used for the erosion calculation. The analytical work is carried out in ArcGIS software, where critical profiles with the corresponding collection areas were determined and then erosion and peak flows calculated on them and the erosion shear and basic characteristics of direct runoff were calculated. The DesQ-MaxQ program was used to calculate the flows in each catchment. The result of the work is an analysis of the area in terms of erosive shear to the Brno dam.
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Evaluation of the river system of the Odlezelské (Mladotické) Lake basin as a potential source for sediment transport
Mužák, Petr ; Kliment, Zdeněk (advisor) ; Šobr, Miroslav (referee)
The status of the river network is essential to understanding the fluvial system of the basin. Erosion and accumulation activities of the river system led to changes in the river channel which caused the increased sediment transport and contributed to the silting of the Odlezelské (Mladotické) Lake. This study aimed to evaluate the status of the river system of the Odlezelské Lake basin and to identify and characterize its erosion and accumulation of landforms. The field survey of the Odlezelské Lake basin applied the hydro morphological characteristics monitoring (HEM) method extended by the record of erosion and accumulative landforms. The Mladotický stream recorded the highest representation and area concentration of erosion landforms. The Potvorovský stream showed the highest density of accumulation of landforms. Anthropogenic activity changed the mapped part of the lake basin in 47 percent of sections which exhibited a lower degree of erosion and accumulation of landforms. Beaver population activities also significantly influence the fluvial dynamics of the river system. Keywords: river channel, fluvial dynamics, sediment transport, Odlezelské (Mladotické) Lake
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18th International Conference on Transport & Sedimentation of Solid Particles
Sobota, J. ; Vlasák, Pavel ; Matoušek, Václav
The Proceedings comprise text of 50 oral contributions dealing with two-phase and multiphase flows, Newtonian and non-Newtonian flows, designing, optimization and operation of hydrotransport and pneumotransport systems, wear and corrosions, pumps and valves, sediment transport in rivers and water reservoirs, hydraulic storage of tailings, sedimentation and thickening, methods and techniques of measurement, instrumentation for laboratory, field and industrial systems.
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Erosion of agricultural land and its importance for siltation and eutrophication of reservoirs in the Czech Republic
Krása, J. ; Jáchymová, B. ; Bauer, M. ; Dostál, T. ; Rosendorf, P. ; Hejzlar, Josef ; Borovec, Jakub ; Bečička, M.
In 58 large catchments of the Czech Republic (covering ca 35000 km2) the sediment transport processes were assessed. Amount of sediment flux into the streams and reservoirs from agricultural land was estimated. Sediment retention in all reservoirs was considered based on reservoirs‘ outflow. For thousands of small ponds the volumes and outflow had to be estimated based on reservoir areas and specific flow rates in catchments. The distributed approach allowed considering importance of particular agricultural fields for stream silting. The maps of annual sediment flow in all streams were derived. The sediment fluxes cause serious problems not only concerning eutrophication. For example Vltava river watershed up to Slapy dam (12 965 km2) exports 2.34 million tons of sediment by water erosion annually. 626 thousand ton is exported into the streams, and 615 500 t is then deposited in the reservoirs.
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Methodology for assessment of vulnerability of water reservoirs from eutrophication caused by supply of phosphorus from soil erosion
Krása, J. ; Dostál, T. ; Rosendorf, P. ; Hejzlar, Josef ; Borovec, Jakub
Vodní nádrže v ČR jsou dlouhodobě ohroženy eutrofizací (podmíněnou přebytkem dostupného fosforu), sedimentem a dále toxickými látkami (rozpuštěnými, ale často rovněž vázanými na sediment). S narůstající extrémností klimatu ve středoevropském regionu je v posledních letech zanášení nádrží ještě eskalováno. Za účelem celorepublikového posouzení rizika eutrofizace povrchových vod je řešen projekt QI102A265 „Určení podílu erozního fosforu na eutrofizaci ohrožených útvarů stojatých povrchových vod“. Metodika se skládá z několika částí: posouzení stavu trofie povrchových vod a ohroženosti nádrží; bilanční vyhodnocení jednotlivých zdrojů ve velkých povodích; kvantifikace erozního smyvu; kvantifikace transportu sedimentu do jednotlivých nádrží; určení celkového a rozpuštěného fosforu pocházejícího z eroze, resp. určení eutrofního potenciálu erozního smyvu. Stručně jsou zmíněna možná ochranná opatření proti vstupu erozního smyvu do nádrží.
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Assessment of vulnerability of water reservoirs to sediment loads and eutrophication caused by soil erosion
Krása, J. ; Rosendorf, P. ; Hejzlar, Josef ; Borovec, Jakub ; Dostál, T. ; David, V. ; Ansorge, L. ; Duras, J. ; Janotová, B. ; Bauer, M. ; Devátý, J. ; Strouhal, L. ; Vrána, K. ; Fiala, D.
This methodology has the following aims: Allow any investigator to evaluate the erosion and transport of sediment phosphorus in large river basins. Allow investigators to estimate the importance of erosion for the eutrophication of the target reservoir. Allow investigators to estimate the importance of other sources of phosphorus in the watershed. Allow investigators to estimate the behavior of the other tanks in the current state of phosphorus loads from the watershed. The methodology is focused on solutions in large river basins.
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