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Selected issues in hydrology and hydrogeology of the Trebon Basin
Nymsa, Zdeněk ; Slavík, Martin (advisor) ; Nedvěd, Jakub (referee)
In the last few decades, the average temperatures in the Czech Republic have been increasing, which has led to increase in evapotranspiration. Previous studies have shown that increases in evapotranspiration during the summer months can lead to significant reductions in flows and even to drying up of small watercourses. Additionally, snow cover has also been on the decline in recent years, resulting in no flow enhancement in spring months and therefore lower soil moisture problems ensue. Due to the possible decrease in precipitation and/or increase in evapotranspiration, there is also the risk of less groundwater recharge in the future. The aim of my thesis is to verify the correlation between several selected parameters in the Trebon Basin, namely the relationship between evapotranspiration, precipitation and baseflow and groundwater levels in boreholes. A sub-objective is to verify the long- term evolution of these parameters in the Trebon Basin. Atmospheric precipitation and its variability during the year have not changed since the 1960s, while the magnitude of potential evapotranspiration has statistically significantly increased over this time and its variability during the year has decreased. The difference between atmospheric precipitation and potential evapotranspiration has been...
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Changes in groundwater recharge and base flow in mountain catchments in Czechia due to changes in snow storages
Kožíšek, Matěj ; Jeníček, Michal (advisor) ; Šípek, Václav (referee)
Changes in groundwater recharge and base flow in mountain catchments in Czechia due to changes in snow storages The diploma thesis deals with the topic of replenishing groundwater reserves due to the melting of snow cover. The main motivation is the importance of the topic for understanding the changes in the hydrological regime caused by decreasing snow cover and small number of research papers on this topic. The aim of the work is to find the relationships between changes in snow cover and groundwater recharge and runoff parameters in the warm part of the year. The main part of the thesis is work with the HBV model. The parameters of underground water reserves and the size of the basic runoff are modeled using climate data and snow water value data from selected mountain basins of the Czech Republic. The Mann-Kendall test and Theil- Sen linear trend is used to evaluate trends in data. The relationships between individual parameters, expressed by Spearmann correlation tests are also examined. The impact of climate change and the associated increase in air temperature was reflected in all runoff and groundwater parameters. Trends were observed at the annual and especially the monthly level. The impact of climate change and the associated increase in air temperature (0.24 to 0.4 řC/decade) was...
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Methodology of baseflow assessment
Patzeltová, Lucie ; Hrkal, Zbyněk (advisor) ; Vencelides, Zbyněk (referee)
This thesis provides an overview of methods used for determining the baseflow as one of the essential components of Water balance. Knowledge of the baseflow is important for determining the size of natural groundwater resources, as it gives valuable information on the possibilities of their exploitation. The thesis provides an overview of the historical development of the methodology in this field. Selected methods are compared based on the difficulty of their application, data input requirements and the quality of outputs. Several case studies dealing with the application of selected procedures are presented. Furthermore, the Kamenice river basin is presented as a pilot area. Based on its natural conditions and the form of available data inputs from the Hřensko measurement profile, a suitable method for calculating the baseflow is chosen and applied.
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Comparison of selected methods of calculating baseflow in a small basin and evaluate influnence of baseflow to concentrations of phosphorus in total runoff.
ŠVARCOVÁ, Eliška
This thesis is focused on the methods of separation of baseflow and comparing of these metods. It is analyzing concentrations of total phosphorus in the total runoff and influence of baseflow to concentrations of phosphorus in total runoff. The studied area is subcatchment P52 in the catchment Kopaninský flow. Subcatchments P52 is small (64,93 hectares), drained agro-forestry catchment in Českomoravská vrchovina (Czech-Moravian highlands), with a large proportion of forest area (64% forest and 31% of arable land). Studied the period is hydrological period 2009 - 2011. To obtain the necessary results are used daily flow, daily concentrations, daily precipitation of rain gauge station Velký Rybník and monthly precipitation from rain gauge stations of the ČHMŮ (Czech Hydrometeorological Institute) in Humpolec. For the separation of the baseflow and comparison of methods were selected five methods: - method of digital filter according to Chapman (1999), - method UKIH designed by Institute of hydrology (1980), - method RDF proposed by LINE AND Hollick (1979), - method FUKIH proposed by AKOSY AT. AL. (2009) and - method of Kille (1970). All methods are simple to perform and not challenging to input data. When comparing methods, the main problem is that, the results obtained by different methods are very different. Another point of this work is to evaluate the concentrations of total phosphorus in the tatal runoff. Here is analyzed series of daily concentrations of total phosphorus and monthly and annual average concentrations. Low and high concentrations are compared with the values ??of precipitation and clinks are searched between these values. The main problem is that, the concentration of phosphorus are not dependent only on precipitation. The last point is solution of influnence of baseflow to the amount of total phosphorus in the runoff. Here is used the procedure which described BYSTŘICKÝ in its work (2012). There are determined values concentrations typical of baseflow, for direct runoff and total runoff. Groups of values ??are mutually tested and compared. The results show that, the baseflow is negligible contributor of phosphorus to the total runoff, but to achieve more accurate results would be needed to analyse a longer time period (eg 10 years) and compare the results with several different river basins.
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Concentration of nutrients (nitrogen, phosphorus) in groundwater and baseflow
PETRÁŠKOVÁ, Kateřina
The aim of my bachelor thesis is explain genesis and difference of basic nutrients - nitrogen, phosphorus, and describe its cycle and occurrence in water. The second part of this thesis is about groundwater, its cycle and difference in human society. It describe natural and anthropogenic impact (mainly agriculture) influence over quality of groundwater. The next part is about concentration of nitrogen and phosphorus in groundwater in Czech Republic and over the world and its development. The genesis of runoff and its dividing is describe in the fourth part. In this part there are also methods of baseflow separation. The last part is about development and concentration of nitrogen in baseflow.
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Methods of runoff components separation
KUBEŠ, Ondřej
The paper deals with monitoring and measurement of runoff. This is particularly important to identify water supplies in the catchment area, or timely detection of extreme hydrological events such as floods and droughts, and because of the potential rate of spread of pollutants. The value of the runoff is particularly important for irrigation needs for agriculture. Further work is focused on the individual components of runoff, the methods used for their separation and a detailed description of various types of runoff. The practical part includes measurement of the discharge at the Jennínsky stream catchment, located near the border with Austria, the Český Krumlov district. For analyses discharge from the hydrological years 2005 ? 2008 was chosen. And using the three selected methods of separation (method GROUND, method and method MPGM digital filter according to Chapman), which are further described and explained. These methods divide runoff into the baseflow component and direct runoff component. These results are further compared with the method of reccesion curve analyses performed on four events. The work should show the differences in results of various methods.
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