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The project was aimed at comparing suspended load in four model river basins which are about of the same area and where each of them represents different geographical environment within the territory of the Czech Republic. We have chosen the Blšanka River basin, and basins of the rivers of Lužická Nisa, Loučka and Olšava as model territories. We have developed a model of the erosion risk for these basins. The model is based on a multi-criterion scale evaluation of chief erosion factors so that we can compare the potential of river basins for the sediment transport and define the chief risky areas. The sediment transport was evaluated for closing profiles of model river basins. We defined basic types of run-off situations to characterise the relationship between the content of sediments and the water flow. Mains trends in the development of erosion processes and suspended load are discussed in conclusion.

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

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

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

Changes in the hydrological cycle are one of the expected impacts of climate change. Until recently, Central European mountain ranges have not been considered to be affected by water scarcity. Nevertheless, recent years have suggested an increasing risk of drought occurrence also in these regions, which have a major impact on the water supply to rivers that drain them. The master thesis deals with the evaluation of hydrological drought in the headwater areas of three catchments in the Ore Mountains for the period from 1967 to 2018. The main aim is to compare the of hydrological drought characteristics in the catchment areas of upper Svatava River, upper Rolava River and Načetínský brook based on available hydrological and climatic data. In connection with this, the work aims to detect the long-term trends of drought occurrence in selected basins. Furthermore, the emphasis is given on the evaluation of natural conditions, especially the historical and current land cover changes in the study catchments. The results point to a significant change in the seasonality of the occurrence of hydrological drought in the second half of the studied period, when the streamflow deficits concentrate between August and October. Furthermore, increasing trends in deficit volumes were found in the catchment areas of...

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 Odlezelské Lake is a natural, landslide-dammed lake in western Bohemia. Its lake basin is silting intensely and its volume decreases; it will be completely silted in the future. This work aims to evaluate the siltation of the lake primarily by evaluating the suspended load regime of its tributaries and comparison with data from bathymetric measurements. Within this work, data from the station network of the Department of Physical Geography of the Faculty of Science of the Charles University were used, which was statistically processed in order to describe the hydrological and suspended load regime. In addition, flow speeds in the inflow part of the lake were measured during two precipitation-runoff events using ADCP. The results show that most of the suspended load is transported during flood episodes, in contrast to the runoff, there is a significant interannual variability in the suspended load regime. Oppositely, the comparison of the suspended load regime and the bathymetric data proved as impossible due to a high sensitivity of the data.

Water erosion in the Czech Republic is the largest phenomenon that degrades and seriously damages agricultural areas throughout the country. It is influenced by many factors that have changed since the 1950s. Various methods are used to assess the intensity of erosion. In the Czech Republic, the USLE (Universal Soil Loss Equation) is the most widely used equation, which is the cornerstone of the model used in this work. I quantified and localized water erosion in the Odlezel lake basin for individual scenarios of land use change using the WaTEM / SEDEM model. The results show the seriousness of water erosion in relation to landscape management, as the modeled intensity of erosion in 2018 is almost the same as in the period of collectivization. The results of modeling are confronted with changes of individual input factors, with measured data of river sediment export in the Mladotický brook and up to date knowledge about clogging of the lake basin. Key words: water erosion, modeling erosion, WaTEM/SEDEM

Africa is a heterogeneous environment that is affected by natural and anthropogenic processes. This thesis uses a review method to characterize the natural environment of the continent, present possible classifications of natural conditions and to describe the transformation of this environment. The main methodological aim of the thesis was to determine areas threatened by biodiversity loss due to anthropogenic pressures based on a new classification of the natural environment on a continental level. This was executed by methods of environmental stratification and subsequent environmental classification. Thus, this thesis presents a classification of the natural environment on the basis of homogenous units determined by bioclimatic variables and terrain, which are subsequently related to the biodiversity of birds, amphibians and mammals and to an anthropogenic influence represented by anthropogenic biomes. Finally, the share of protected areas is executed in relation to this anthropogenic transformation of the natural environment. Therefore, the thesis is quite a unique approach, as it takes into account a combination of both physical and socio-economic factors at a continental level. The final output consists of a map of the anthropogenic transformation of Africa's natural environment in the...

The doctoral thesis deals with the evaluation of influences of causal factors that significantly affect runoff processes in landscape. The research is mainly focused on the examination of land and soil cover impacts and partially pays attention to the effects of surface drainage and snow cover. The main effort was to find out the extent of influences of each individual factor on runoff from a different type of landscape. In order to find the correct answer, a methodical approach was applied to small experimental paired catchments where the research has been continuously undergoing since the year of 2006 (the presented results have been collected for 11 years of observations). The small experimental paired catchments are located at the foothills of the Šumava Mountains and they represent small area neighbouring catchments of similar physical-geographic and hydrographic conditions. The catchments were selected as the comparative ones where the main differences are the landscape and soil cover. Moreover, the character of surface drainage is regarded to be an important variable. In the catchment area of the Zbytinský Brook, there predominates the grassland which is largely drained by the subsurface drainage system. In the catchment area of the Tetřívčí Brook the dominant cover is formed by the forest...

This thesis deals with rainfall and water runoff regime in the catchment area of river Klabava. The aim of this thesis is to find changes in the rainfall-runoff regime during the period of observations (1950-2014) and if so, were these changes caused by climate changes or human activities. The research part includes description of rainfall-runoff process and Klabava catchment area description. In the applied part there is an analysis of precipitation - runoff regime for long-term time series of average and minimal annual, monthly and seasonal discharges and annual, monthly and seasonal precipitations using single and double mass curves and statistical tests testing absolute homogeneity, relative homogeneity and trend (by Mann-Whitney-Pettit, Alexandersson, Mann-Kendall tests). The tests were performed by freely available software AnClim designed for these purposes. Mann-Kendall test was performed by MULTMK/PARTMK available as a MS Excel macro for free. Plus, there is basic discussion of floods in Klabava river basin and flood seasonality. The homogeneity tests haven't found many changes at all, most of the detected changes concern the minimal runoff time series. The precipitation annual amount was detected with a raising trend, while the runoff time series seem to have no trend at all. Achieved...

This thesis deals with the evaluation of hydrological properties variability of soils in forest catchment Tetřívčí brook in the source area Blanice based on selected hydropedological characteristics with respect to soil type, vegetation cover and character of slope. The selected hydropedological characteristics are maximum capillary water capacity, full water capacity, soil infiltration capability - infiltration rate and cumulative infiltration and retention potential of soils. In sum of seven soil subtypes found in forest (coniferous, deciduous and mixed) and meadow (cut and non-maintained) and on the different slope (three categories) were studied in the catchment area. This thesis is built on bachelor thesis, which dealt with the variability of hydropedological characteristics in the experimental pair comparison basins of Tetřívčí and Zbytinský brook. In the thesis were used mainly the measured data obtained from repeated field campaigns in pre- selected sites and data from the database of experimental catchments of Zbytiny. In the selected sites were made soil probes, soil samples were taken using Kopecky cylinders and infiltration measured by a single-cylinder infiltrometer. By laboratory determination and calculation, selected hydropedological characteristics were obtained. The results were...

The connectivity of fluvial processes or hydrological connectivity are terms often used to describe internal linkages in landscape that intensify/reduce water and sediment fluxes as well as the substances they contain. It is based on the concept of landscape connectivity defined, in particular, by fragmentation of landscape and barriers that obstruct the movement of material. While researches focusing on water erosion or runoff focus on the volume of different fluxes, connectivity reveals new information on catchment functioning as well as reactions to various types of stimuli, and thus represents a more complex phenomenon. This master thesis informs about the topic as a whole, it describes the main forms of its modelling and specific influences that have major impact on presented results. Three approaches of modelling were tested. The main concept lies in evaluation of the index of connectivity, firstly, with approach proposed by Borselli et al. (2008) and implemented in software ArcGIS and secondly, in software SedInConnect 2.0. The third approach is modelling connectivity in software LAPSUS 5.0 that belongs to landscape evolution models. Modelling in LAPSUS proved that using even this indirect method for evaluation of hydrological connectivity is a suitable approach. Selected area for modelling...

jezero je nejmladším přírodním jezerem v Česku. Od jeho vzniku dochází intenzivnímu zanášení jezerní pánve a jezero spěje k mapování jezerní pánve, analýza jejích změn a zanášení jezera. Byla zpracována tři etrická měření - letech 2003 a 2014 byly hloubky odečítány z echolotu a měření příčných profilech, v roce 2017 byl použit modul RiverSurveyor na dálkově automatickým ukládáním dat. Všechna měření byla zpracována interpolaci byla využita metoda ordinary kriging. Pro analýzu změn jezerní pánve byla použita i data z porovnání zjištěných dat vyplývá, že objem jezerní pánve se zmenšil mezi lety 1972 a 2017 o 40 . Na základě změn objemu byly stanoveny rychlosti zanášení jezerní pánve, které se ale při porovnání různých měření liší. Podle dat z let 2003 a 2017 až v

Although gully erosion represents an important process of land degradation, only a few studies in the Czechia have quantified the gully erosion rate yet. Because of the complex and nonlinear dynamics, the estimation of the gully erosion rate requires a long term and technically difficult research. However, a recent methodological approach in dendrogeomorphology allows to reconstruct a gully development and assess gully erosion rate. Based on geodetic survey, a detailed mapping of four gullies in the Polomené Mountains was carried out. Subsequently, the gully erosion rate was evaluated by the analysis of 73 exposed roots of broadleaved trees. The first erosion episode was detected in 1981, however, most of the roots were exposed in the last 15 years. Gullies have been forming non-continuously showing median erosion rates between 10.0 to 13.4 mm/year. Even though topographic parameters and land use changes in drainage basin area may affect the intensity of erosion, most of the erosion episodes have been probably triggered by extreme rainfall events. This study exemplifies that intesive gully erosion may occur even on forest soils. Vegetation cover influences a morphology of gully slopes, but its ability to prevent intensive gully erosion is limited. Keywords: gully, erosion rate, exposed roots,...

The aim of this thesis is to devise a method for objective classification of floodplain based on spatially accurate data from UAV that allows identification of the fundamental features of floodplain and channel arising from or affecting by the floods activities. Background research is focused on floodplain forming processes; types of flood on our territory and its geomorphological effects, as well as a brief description unmanned aerial vehicle and their applicability in natural science and the flood. Proposed method was carried out on the test section - a part of meander of Javoří stream in Šumava Mountain - then was tested on complex meander belt of the same stream. Proposed method is based on applicability of standard objective classification. Elementary products from photogrammetric analysis - 2D orthophoto and 3D digital surface model - are used as basic input data. Another aim of theses is to discuss applicability of this method for assessment of fluvial form, its limits and potential development. The results indicated that success of classification will increase significantly the involvement of 3D data to classification, which from standard data from the UAV, despite the lack of absence multispectral bands doing a very valuable source of information for mapping and analysis, for example, the...

Muddy floods phenomenon Department: Department of Physical Geography and Geoecology, Faculty of Science, Charles University in Prague Supervisor: doc. RNDr. Zdeněk Kliment, CSc. Abstract: Muddy floods represent a movement of accumulated material from agriculture areas during floods trigerred by heavy rainfall (with intensity that exceed 30 mm/hour). Areas where moody flows occur are typical with steep slopes, loess, thalweg cultivation and growing crops with erosion dangerous. The most intense moody floods occur particularly in central Belgium, France, Netherlands and Slovakia. The moody floods are caused by growing suburbanization, enlarging area of farmland, tamping during agricultural mechanization or transformation grassed areas into cultivated land. Great attention should be paid to measures against erosion because water erosion with heavy rainfalls increase amount of accumulated material, what amplify negative impact of moody flows. The most suitable solution is combination of agrotechnological, technical and organizational measures. The negative consequences of moody floods are e.g. soil degradation, flooding up nutrients, carrying topsoil or transportation of accumulated material into populated area, where high economical and emotional damage may be inflicted. It is necesery to take floods triggered...

This Bachelor thesis deal with the problems of floods on river Sazava. There are described types and characteristic of floods. The thesis sums up methods of historical flood research. It reviews all known floods on Sazava since 1515 up until 2006. While researching these floods, some previous works about Sazava and also historical documents from archives were used. From the found events, the seasonality of floods is made. The floods in 1909 was researched in more detail in the Kacov profile. The cause-factors of the floods and their process are studied closely as is the process of the flood itself. For the Kacov profile, the specific curve was calculated and the flood wave was described. The progression times of the flood were evaluated. Key words: flood, historical flood, Sázava, Kácov, sezonality, 1909

The diverse region of southern Africa is affected by several changes of the natural environment. This thesis characterizes the region of southern Africa and evaluates the state and development of these natural conditions and environmental problems in four main categories of physical geography - climate, vegetation, soils and water. A literature review is compiled and processed focusing on studies by field experts, which describe the main issues in these categories. Particular problems which the region encounters are described on a global, regional and local scale. The main problems are: changes in temperature and precipitation, land cover change, deforestation, desertification, threats to biodiversity, soil erosion and water availability. Overall, changes of the natural environment in southern Africa are caused by climate change and anthropogenic activity. However, human activities cause a greater impact as a result of their "indirect influence" on climate conditions and "direct influence" on vegetation conditions. Key words: Africa, southern Africa, natural environment, climate, vegetation, soils, water

The main task of this diploma thesis is to evaluate function of system of open drainage channels and its impact on runoff from Tetřívčí brook forest catchment in Šumava mountains region, upper basin of the Blanice River. Catchment area is only 1,62 km2 and total length of all channels is over 12 km, so it's very important feature of this catchment. The first task was to explore to explore all the channels and set them to the map. Most of used data were measured manually, only precipitation and water level in main stream were measured by automatic gauges. It's not possible to compare results with state without channels, what is the main obstacle for data analysis. Measured channels normally contribute to total catchment runoff by 6 % to 39 %. About 20 % of channel length participate in runoff process in dry periods, in wet periods it can be even 90 % of channel length, what indicates functionality of drainage system. Actual soil saturation in the catchment is very important factor, it's expressed either by index API 5 (based on precipitation) or by groundwater level in 5 measured in separate drills. It's proved by channels responses in well-saturated periods. Runoff in measured channels raises up significantly after even very small precipitations of 1,7 mm. All results are suggesting, that total...

This thesis is focused on fluvial dynamics in gravel bed mountain stream. As model basin was chosen Roklanský brook catchment in Šumava mountains, some methods was used on a part of its tributary Javoří brook. We wanted to make an analysis of Roklanský brook catchment by characteristics and course of channel, river floodplain and fluvial erosion and accumulation forms, to find context and factors natural and anthropogenic influenced character and dynamics of the fluvial system. There were used methods based on field mapping channels and fluvial forms, grain size distribution, lidar data, historical aerial photos by 1949 to 2015, bankfull discharge and study old maps and other historical documents from archives. The results show that fluvial system of Roklanský brook has high rate of dynamics. We get known that placement of accumulation and erosion forms relates with longitudinal slope of channel and geological forms. The train of channel changes often, in past according to anthropogenic intervention. In floodplain of Javoří brook is a lot of potential channels. We get known height of water level which causes significant channel changes. Key words: gravel bed streams, fluvial dynamics, field mapping, historical aerial photos, lidar data, bankfull discharge, historical maps, Šumava mountains,...

Assessment the effect of revitalizing measures of chosen peat bogs in the upper Vydra River basin on their water regime Abstract: Despite a number of research projects, the influence of peat bogs on the hydrological regime remains a largely unexplored topic. In the past, several peat bogs in the Šumava National Park were exposed to a very strong anthropogenic pressure. Subsequently, revitalizing measures were applied to mitigate the impact of human interventions, to stop the degradation of these precious habitats, and to reform the disturbed peat bog water regime. This thesis is focused especially on fluctuations of water table level and on the hydrological regime in the catchments of Rokytka and Cikánský Brooks. Thesis further develops the topic solved in author's bachelor thesis called "Peat bog revitalizing measures and their effect on runoff dynamics in the Otava River headstream area." It contains experimental research of the influence of drainage canals and revitalizing measures on water table fluctuation. It also aims to identify the extent to which meteorological factors contribute to changes in groundwater level and to assess the present state of revitalization measures and their influence on the runoff regime. Key words: peat bogs, revitalizing measures, Šumava Mountains, water regime

In this thesis are based on the scientific literature defined selected hydropedologic characteristics and is described their impact on motion and amount of water.in the soil and also on the runoff process. In this thesis are quoted methods that can be used for measuring motion and amount of water. Data obtained on several field campaigns and continuous measurement of soil moisture sensors Virrib was processed. Field campaign took place in catchments of Zbytinský and Tetřívčí stream, which are paired comparative experimental catchments. The continuous soil moisture was measured at three places, which differ in their vegetation and soil cover. Data Analysis was concentrate to evaluate soil moisture measured by Virrib, which were compared to soil moisture determined during field campaigns. The continuous soil moisture was measured at three places, which differ in their vegetation and soil cover. The results show that differences and similarities in the vegetation and soil cover greatly reflect on soil moisture. Subsequent comparison of two differently obtained soil moisture should show that the values obtained from Virrib are representative. But comparations of values discover, that in Virrib measurement can be found some inaccuracies. Keywords: hydropedological characteristics, runoff process,...

CHANGES OF RAINFALL-RUNOFF REGIME IN THE ŠUMAVA / BOHEMIAN FOREST REGION Abstract: The goal of this thesis is the evaluation of changes in rainfall-runoff regime in the Šumava region from time and spacial point of view. The thesis includes research and applied part. The research part is dedicated to the methods of evaluation of runoff changes and their possible causes in the Šumava region. In the applied part there is an analysis of precipitaion - runoff regime for long-term time series of average annual and monthly discharges and also annual and monthly precipitations for selected gauging stations in Czech, German and Austrian part of Šumava using absolute and relative homogenity tests and Mann - Kendall test for long-term trend. The results of this thesis showed significant changes in rainfall and runoff seasonality. One of the main aims of this thesis is the identification of possible orographical effect or the difference between windward and leeward part of Šumava. In conclusion the achieved results are evaluated, discussed and compared with subject publications. Key words: absolute homogeneity, land-use, Mann - Kendall test, runoff, basin, discharge, relative homogeneity, season,precipitation, trend, Šumava

The aim of this Bachelor's thesis is to analyze trends in the development of runoff and selected features of surface water quality in the drainage basin of the Blšanka river. The thesis consists of a research part and a practical part. The research part examines scholarly literature and describes changes in the runoff and water quality depending on climate change as well as changes in the land use. The practical part processes the data from the Blšanka drainage basin from the end of the 1970s until today. The trends evaluated by the Mann-Kendall's test include the development of the average monthly flow rates, the average monthly temperatures from weather station in Žatec and the monthly amount of precipitation from the four stations situated in or near the area of the drainage basin. The practical part outlines the development of selected indicators of water quality in Trnovany. Next, it also evaluates changes in the land use in a specific part of the Blšanka drainage basin between the years 1995, 2004 and 2013. Keywords: changes in runoff, climate change, water quality, land cover, Mann-Kendall, Blšanka TRENDS IN THE DEVELOPMENT OF RUNOFF AND SURFACE WATER QUALITY IN THE BLŠANKA RIVER BASIN

Athabasca River Basin is located in an area which is affected by many factors. During the last century, the global warming manifests here, resulting primarily into increasing temperatures and glaciers melting in the headwaters area. Much of the middle reaches watershed is used for agriculture, for irrigation of which water from the Athabasca River is pumped. In recent years, controversial development of bituminous sands mining is carried out in the basin. Although it represents a real energy source, the mining requires large amounts of water, which is largely drawn from the Athabasca River. The work therefore analyzes the runoff change in the upper, middle and lower reaches during the last forty years. Along with the time series air temperature changes and precipitation totals, which can also explain runoff changes, are analyzed. Powered by TCPDF (www.tcpdf.org)

During the last 200 years third of all watercourses in Czech republic were modified, stress were massively degraded especialy in the urban areas. The increasing urbanization of the landscape has led in recent years to increased researsch ecology of urban environment, this created the need for quality assesment of watercourses. This bachelor thesis deals with anthropogenically modified flows, quality and change of physical habitat watercourses in urban areas. The main objective of this work is the evluation and presentation of the results of the field survey that was conducted in the Botič river basin using the metodology HEM and HEM-F. Field survey was conducted in the lower reaches of Botič below the Hostivař dam (river km 0,00 to 13,30 km). This section has been most modified in the past, notably in the context of urbanization. In addition to the hydromorphological condition were also mapped fluvial-morphological effects of flood 2013. Based on the evaluation results of the field survey the majority of segments were classified as poor or bad.

This study is focused on the evaluation of selected rainfall-runoff episodes in terms of temporal and spatial distribution of rainfall and runoff in the upper basin of the Blanice River. HEC - HMS model with two variants of spatial discretization was used to achieve the results of the holistic approach. The main input data was quantitative precipitation estimation, which better assessed the spatial variability of rainfall fields than interpolated ground measurements. The model simulated five episodes. Contrary to expectations, southern headstream area of the basin showed lower coefficient of runoff in comparison with its northern part. Precipitation cores of epizods occurred over the northern part of the basin at the outlet. Outputs from the model were evaluated in relation to measurements carried out in the experimental basin Zbytiny. Key words: Blanice River, HEC-HMS, hydrologic modeling, quantitative precipitation estimation