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Interaction of groundwater and surface water under extreme hydrological conditions in the floodplain of the upper Lužnice river
Fialová, Petra ; Janský, Bohumír (advisor) ; Šobr, Miroslav (referee)
The object of this work is an analysis of the influence of extreme hydrological events (floods and droughts) in terms of interaction between groundwater and surface water in the river floodplain. The aim of this thesis is also the evaluation of the hydrological regime of the upper Lužnice basin and evidence of retention potential preserved natural floodplain. The selected objectives of the work were resolved on the basis of the values of groundwater levels and surface water in the area of interest. Based on data from underground wells and a digital terrain model, it was possible to create an image of the distribution of groundwater levels in river floodplains during selected hydrological situations. Data from surface flow was obtained from several habitats in the flow direction Lužnice. This has enabled graphically illustrate individual flood waves and characterize their size, speed and transformation after the passage of a preserved natural floodplain of Lužnice river. Carried out research has been confirmed retention capacity of the floodplain, which is most significant at flow rates slightly in excess of the flow capacity of the river bed. However, extreme floods or in periods with many culminations in a relatively short time leads to reduces water retention capability of the floodplain. In...
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Floodplain mollusc fauna of the lower Elbe and its tributaries -its history, ecology and changes induced by invasion plant species
Horáčková, Jitka
The molluscs are very suitable model of invertebrate group for ecological and palaeoecological studies for their specific traits. In the first part of the thesis, we showed based on available fossil mollusc successions that development of the floodplain mollusc fauna took place quite different way in various river floodplains, depending on their specifics and geographical location, because especially the ones situated in the chernozem area of the Czech Republic had very different history. Detailed processing of five fossil mollusc successions in the lower Ohře River floodplain confirmed the impoverishment of recent forest malacofauna does not relate to natural processes only (chapters 3 and 10), but it arises from historical development of this area which was under permanent stress of the human settlement and agricultural utilization (chapter 1) since the coming of the Neolithic people. We made similar conclusions in case of another 11 fossil mollusc successions in the neighbouring České Středohoří Mts. (chapter 2). In the second part of the thesis (chapter 3), we investigated the ecological patterns responsible for species richness and composition of the floodplain mollusc fauna are especially the elevation and humidity gradient, and then vegetation type and its biomass, light conditions of the...
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Current state of vegetation in the Sázava River floodplain after spring flood in 2006
Klášterková, Hana ; Chuman, Tomáš (advisor) ; Matějček, Tomáš (referee)
In this diploma thesis current state of vegetation cover was analyzed after spring flood in 2006 on the lower section of the Sázava river. Immediately after the flood there were 38 sites with alluvial deposits identified in the floodplain. The differences in species composition and species diversity between sites with alluvial deposits and sites without deposits were analyzed. The data were collected by using phytosociological relevés in pairs i.e. - plot with an alluvial deposit and plot without. There were 86 vascular plant species recorded out of which 10 species were non-native but not invasive species and 7 species were non-native invasive species. Results of this thesis revealed that species composition and diversity of invasive species differ between plots with alluvial deposits and plots without alluvial deposits. Moreover, plots without alluvial deposits host more invasive species. Keywords: vegetation succession, river floodplain, extreme floods, species diversity, plant invasion
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Studie návrhu hydrotechnických a biotechnických opatření na levém břehu řeky Svratky v k.ú. Ujčov, cca ř. km 93,8 - 94,1
Bureš, František
This diploma thesis Study of the proposal of hydraulic and biotechnical measures on the left bank of the river Svratka in the cadastral area Ujčov, of approx. km 93.8 to 94.1, builds on the previous bachelor thesis Study of selected land on the river Svratka in the village Ujčov. This work is a suggestion to adjust the area in terms of the appropriate use of land, which is owned by the author's family. The affected area lies at the weir on the river Svratka and is currently made up of a pool, which is a relic of the arm of Svratka. The pool is followed by a wetland and grassland with wood vegetation. The first part consists of a literature review and analysis of the issue areas, including its historical development. The practical part is focused on individual hydraulic engineering and biotechnical modifications in the area.
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Potential of watercourses restoration measures as a tool for water retention in the floodplain
Zelíková, Nikol ; Matoušková, Milada (advisor) ; Jeníček, Michal (referee)
The object of this thesis is the evaluation of the restoration potential of small hydraulic structures for increasing water retention in river floodplain by using 2D HEC-RAS hydraulic model. A former millrace of the Rožnovská Bečva River was used for the design of restoration measures. The restoration proposal consists of partial modification of the current millrace and new close-to-nature watercourse in the agricultural floodplain. Restoration proposal also includes changes in land use, which consist of grassing and afforestation. The input data used for the hydraulic model are digital terrain model (5G) by ČÚZK, surface roughness parameter and mean hourly discharge data of 1997 (Q100) and 2007 (Q5) flood events provided by CHMI. The results of the hydraulic simulations point to the positive effect of proposed restoration measures especially in the change of flooded volumes (3x higher) and flooded areas (2x higher). The results indicate that restoration measures lead to the flooding from the newly designed watercourse that precedes the flooding from the Rožnovská Bečva River. This brings the possibility of more frequent occurrence of inundation events favourable for water retention in the river floodplain. Keywords: retention, floodplain, restoration, hydraulic structures, Rožnovská Bečva River,...
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Obnova vegetace revitalizovaného úseku řeky Stropnice
HEROVÁ, Zdenka
Three seasons of initial succession were followed in the frame of this thesis after a restoration project in a section of the Stropnice River and its floodplain. The succession tends towards formation of community of alluvial meadows, which is prevailing biotope in the neighborhood of the restored part. Strong factor influencing the course of succession is wetness of the substrate, which is partially given by distance of a site from the water-course and by the difference in the altitude of a site and of the river water table. Synantrophic species were most abundant in the first year (2014), followed by meadow and wetland species (2015, 2016).
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Floodplain mollusc fauna of the lower Elbe and its tributaries -its history, ecology and changes induced by invasion plant species
Horáčková, Jitka ; Juřičková, Lucie (advisor) ; Pokorný, Petr (referee) ; Čejka, Tomáš (referee)
The molluscs are very suitable model of invertebrate group for ecological and palaeoecological studies for their specific traits. In the first part of the thesis, we showed based on available fossil mollusc successions that development of the floodplain mollusc fauna took place quite different way in various river floodplains, depending on their specifics and geographical location, because especially the ones situated in the chernozem area of the Czech Republic had very different history. Detailed processing of five fossil mollusc successions in the lower Ohře River floodplain confirmed the impoverishment of recent forest malacofauna does not relate to natural processes only (chapters 3 and 10), but it arises from historical development of this area which was under permanent stress of the human settlement and agricultural utilization (chapter 1) since the coming of the Neolithic people. We made similar conclusions in case of another 11 fossil mollusc successions in the neighbouring České Středohoří Mts. (chapter 2). In the second part of the thesis (chapter 3), we investigated the ecological patterns responsible for species richness and composition of the floodplain mollusc fauna are especially the elevation and humidity gradient, and then vegetation type and its biomass, light conditions of the...
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Floodplain mollusc fauna of the lower Elbe and its tributaries -its history, ecology and changes induced by invasion plant species
Horáčková, Jitka
The molluscs are very suitable model of invertebrate group for ecological and palaeoecological studies for their specific traits. In the first part of the thesis, we showed based on available fossil mollusc successions that development of the floodplain mollusc fauna took place quite different way in various river floodplains, depending on their specifics and geographical location, because especially the ones situated in the chernozem area of the Czech Republic had very different history. Detailed processing of five fossil mollusc successions in the lower Ohře River floodplain confirmed the impoverishment of recent forest malacofauna does not relate to natural processes only (chapters 3 and 10), but it arises from historical development of this area which was under permanent stress of the human settlement and agricultural utilization (chapter 1) since the coming of the Neolithic people. We made similar conclusions in case of another 11 fossil mollusc successions in the neighbouring České Středohoří Mts. (chapter 2). In the second part of the thesis (chapter 3), we investigated the ecological patterns responsible for species richness and composition of the floodplain mollusc fauna are especially the elevation and humidity gradient, and then vegetation type and its biomass, light conditions of the...
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