National Repository of Grey Literature 83 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Dynamics of surface water quality changes in model headwater areas of the Czech Republic
Fraindová, K. ; Matoušková, M. ; Kliment, Z. ; Vlček, Lukáš ; Vlach, V. ; Šajnarová, L.
River headwaters have a high environmental value. Unfortunately, the biogeochemical processes in headwaters in context of different rainfall-runoff conditions and specific land cover have not been fully examined. This study focuses on changes in correlations of 16 biogeochemical parameters related to different types of rainfall-runoff events and land cover condition for eight headwater catchments in Central Europe. Multiple methods as linear regression, Spearman rank correlation, Principal Components Analysis and C/Q hysteresis loops revealed main relationships. Presence of peatlands and waterlogged spruce forests had decisive influence on the biogeochemistry (mainly for CODMn, humins, Fe, P-PO43− TP, and N-NO3−). The strongest positive correlation of organic matter (CODMn) and Fe is represented in a catchment with the largest area of damaged forest (70%), but with a smaller proportion of wetlands (8%). High flow rates influence the release of greater amounts of organic matter and N-NO3−.
Dynamics of dissolved organic carbon in surface water during extreme rainfall-runoff events
Matoušková, M. ; Fraindová, K. ; Bejčková, M. ; Kliment, Z. ; Vlach, V. ; Vlček, Lukáš
The release of a greater amount of natural organic matter (NOM) within climate change is registered in many catchments with peatbog areas. The aim of our research is to study the dynamics of releasing dissolved organic carbon (DOC) into surface water in headwater areas with peatbogs. DOC concentrations are analysed in relation to extreme rainfall-runoff (R-R) events and according to the hydrological preconditions of the basin. These preconditions are described using selected hydroclimatic variables (14 days before the R-R event). The source data comes from stations of the Faculty of Science, Charles University, and the Czech Hydrometeorological Institute. For the evaluation of relations and processes, the Principal component analysis (PCA), hysteresis loops or Pearson correlation coefficient was used. The lag time of DOCmax for Qmax, the dependence of DOCmax and groundwater levels were studied. The influence of flow rate on the decline and ascent phases of DOC\nconcentrations by hysteresis loops and the influence of the number of partial flow maximums on the amount of transported DOC during the R-R event was analysed. Our first results show that great influence on the dynamic of DOC concentration in surface water has the change in groundwater-levels in the peatbog and the outflow amount during the R-R event. The hydroclimatic preconditions of the basin have also a significant influence on the DOC release. Changes in concentrations during R-R events also occurred for other compounds that were studied additionally. Particularly significant was the increase in metals (mainly Fe, Al, Mn) and base cation (K) and decrease in nitrate nitrogen.
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
Sediment analysis and hydrological regime of water reservoir Všechlapy
Wolfová, Helena ; Šobr, Miroslav (advisor) ; Kliment, Zdeněk (referee)
This masters thesis is focused on the evaluation of anthropogenic sediment pollution and the total estimate of the siltation of the Všechlapy reservoir. Based on bathymetric mapping, the morphometric parameters of the Všechlapy reservoir were evaluated. By digitizing the old map of the previous terrain before the construction of the dam, its current siltation of 15.7 % with bedload sediment was determined. Bedload sediments and river sediments of two streams were collected, in which the grain size analysis of the fine-grained fraction and the chemical analysis by pseudo-total digestion were performed to determine the content of metals and metalloids. Evaluation of sediment pollution was performed using geoaccumulation index using global and local background values of the natural environment. It was found that the Bouřlivec stream was rated the worst pollution classes in terms of cadmium, arsenic, copper, lead, zinc and nickel. Based on their chemical properties, these increased concentrations were also reflected in the samples taken from the bed of the Všechlapy reservoir. Part of this thesis was also the review of the hydrological regime of the Všechlapy reservoir. key words: sediment pollution, water reservoir Všechlapy, Bouřlivec stream basin, bathymetric survey, aqua regia leaching
Changes of rainfall-runoff regime in selected mountain areas of the Czech Republic with respect to their location and side exposure Preparation of precipitation datasets
Kalista, Tomáš ; Kliment, Zdeněk (advisor) ; Popová, Jana (referee)
The main topic of bachelor thesis is the evaluation of precipitation in selected mountains of Czechia. Precipitation regimes in mountain areas are very variable and depend on many factors, which are properly described in the research part of the work - synoptic situations, altitude, mountain orientation. These factors can lead to inequality in distribution of precipitation, which may result in windward and leeward effect or rain shadow. The main goal of the study is to analyze the frequency of synoptic situations that can clarify rainy and dry mountain areas. The work also contains analyzes of average annual totals for ten-year to twenty-year periods in selected mountain areas using cartograms and graphs of precipitation totals in connection with station altitudes. The secondary goal of the thesis is the preparation and completion of dataset files for following studies. Using the above methods, the strength of the windward and leeward effect in most of the studied mountains was clarified, which is related to the findings on the predominant influence of cyclonic synoptic situations coming from the west. Key words: precipitation, synoptic situations, windward and leeward effect, rain shadow, major mountains areas of Czechia
Water retention in experimental waterbasins with focus on histosols
Vlček, Lukáš ; Šefrna, Luděk (advisor) ; Kliment, Zdeněk (referee)
This thesis is being written within the framework of the project GA UK 2371/2007 "Water retention in spring areas as a tool of integrated anti-floods protection and solution of problems with dryness" at the Institute of Physical Geography and Geoecology. The influence of histosols on retention, especially in the National Park of Šumava, is a delicate topic because of collision of nature protection and valuable biotopes preservation on one hand and countryside utilization for anti-floods protection on the other hand. The thesis follows the bachelor thesis "Water retention of histosols". It includes a detailed pedological analysis of the basins of 'Rokytka' and 'Černý potok'. The result of the thesis is water retention determination in the basins and calculation of overall soil retentive potential. The thesis also addresses the analysis of the influence of organic soil on retentive potential of countryside. Keywords: water retention, histosols
Assessment of physical habitat quality as a basis for restoration of the Klíšský Brook
Vrška, Jaroslav ; Matoušková, Milada (advisor) ; Kliment, Zdeněk (referee)
This bachelor thesis is focused on the issue of evaluating changes in physical habitat and possible revitalization of Klíšský stream. The bachelor's thesis uses the method of hydroecological monitoring HEM (Langhammer 2014), according to which the evaluation and presentation of the results of field research was performed. The research part of the thesis briefly summarizes the current knowledge in the field of hydromorphology. Furthermore, the research part focuses on current knowledge dealing with the evaluation of the effects of revitalization measures. The current state of the Klíšský brook is described and on the basis of the obtained data, data are collected as a basis for a possible revitalization study of selected sections of the stream. The negative anthropogenic influences acting on the given locality are also summarized. The performed hydromorphological survey and further analyzes are the basis material for further preparation of individual complex revitalization measures. Keywords: hydromorphology, fluvial-morphological characteristics, channel route, riparian belt, flood plain, restoration, restoration efect
The assesment of soil erosion processes by using WaTEM/ SEDEM and USPED models
Vysloužilová, Barbora ; Kliment, Zdeněk (advisor) ; Kadlec, Václav (referee)
The water erosion is considered as the most important factor having impact on the agricultural land degradation. In the past, many methodes of soil erosion processes by using mathematical models has been developped. The mostly applicated is the universal soil loss equation USLE. The USLE equation has been used as the basis for new erosion models WaTEM/ SEDEM (Van Rompaey a kol. 2001, Van Oost a kol. 2000, Verstraeten a kol. 2002) and USPED (Mitášová a kol., 1996). The two of them are applicated in the experimental catchement of Černičí. The WaTEM/ SEDEM model is able to count the river sediment export as well. The intensity of erosion processes is increasing during extraordinary rainfall - rainoff events. This diploma thesis is evaluating their causes, frequency and course from two points of view: the course of runoff and the sediment transport. The water quality is also evaluated. KEY WORDS: erosion, extraordinary rainfall - runoff event, USPED, WaTEM/ SEDEM
Ecological survey and assessment of streams within European Standards. Application in the Rolava River basin.
Beranová, Zuzana ; Matoušková, Milada (advisor) ; Kliment, Zdeněk (referee)
This thesis deals with implementation of Water Framework Directive (2000/60/EC) in the Czech Republic. The study area was the Rolava River basin in the Ore Mountains (northwest of Bohemia). The ecological status assessment was applied to both - the main stream and relevant tributaries. Available hydrobiological and hydrochemical data enhanced with the field hydromorphological survey using the Hydroecological monitoring (HEM, Langhammer, 2007) were applied in this thesis. Results of the field survey were compared with two ecomorphological methods: LAWA-FS (LAWA, 2000) and EcoRivHab (Matoušková, 2003, 2007). As a final result, it was found out the water body on upper course of the Rolava River achieved good ecological status. Water body on lower course of the Rolava River and of the tributary the Nejdecký Brook were classified as not achieving good ecological status. The Rolava catchment has very specific conditions and huge potential to achieve the good status in the future.
Role of evaporation in the hydrological balance of small catchment
Šereš, Michal ; Kliment, Zdeněk (advisor) ; Matějíček, Luboš (referee)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SCIENCE INSTITUTE FOR ENVIRONMENTAL STUDIES ROLE OF EVAPORATION IN THE HYDROLOGICAL BALANCE OF SMALL CATCHEMENT bachelor thesis - MICHAL ERE Abstract This bachelor thesis called Role of evaporation in the hydrological balance of small catchment uses the measured data from an experimental drainage basins Zbytiny in the source area of Blanice in umava mountains. Its aim is to find appropriate ways of calculating a more accurate determination of the proportion of evapotranspiration for water balance of small watersheds with different land use cover.

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