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Changes in extremity and seasonality of floods in the Zdobnice River basin
Čermák, Daniel ; Langhammer, Jakub (advisor) ; Šobr, Miroslav (referee)
The object of the bachelor thesis is to analyze the change of extremity and seasonality of floods in the Zdobnice basin. The literary research comprehensively presents floods with description of the biggest historical floods in the Czechia and in the Zdobnice basin. The literary research also includes the physical-geographical characteristic of the studied area. The practical part is based on the daily flow data analysis, obtained from CHMI (Czech Hydrometeorological Institute). Runoff analysis is performed on the base of these data, with focus on extreme flows. To compare the seasonality change, data series is divided into two periods (1945-1969 and 1970-2014), which point of change was determined by Pettit's and Buishand's homogeneity test. Seasonality change is compared by directional statistics, polar graphs, curves of cumulative frequency and flood index. As a result of these methods, it is found that in the second period, the flood risk is greater in earlier parts of the year. It has been also found, that there are more flood events in July. Key words: Floods, discharge, hydrological extremes, historical floods, seasonality, Zdobnice
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Seasonal variability of plant secondary metabolism (Artemisia sp.)
Koutská, Barbora ; Weiser, Martin (advisor) ; Dostál, Petr (referee)
Plant secondary metabolites (SM) are widely used by humans in many ways (pharmacy, biotechnology etc.). For making their use even more effective, it is important to know the seasonality of these chemicals in plants and what affect those changes. Three Artemisia species (Artemisia annua, A. absinthium, A. vulgaris) were cultivated during one vegetation season (from April to September 2016). Plant growth parameters and the beginning of their generative stages were observed, and leaf samples were collected regularly. Samples of some plants were collected repeatedly. A generalist herbivore (migratory locust), was used as a proxy for studying changes in plant secondary metabolism during the vegetation season. The results proved presence of defence secondary metabolites in plants except A. vulgaris species where the role of SM in defence was not shown. Levels of SM changed nonlinearly during the vegetational season and were time-dependent. Plant size did not influence the levels of SM in plants. Levels of SM were low at the beginning of the experiment followed by rapid increase and remaining on maximal levels. The plants which lost their biomass repetitively grew slowly and bloomed later than the plants which were clipped only once. A delay trend showing seasonality of the plant SM was not proved. In...
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Rainfall-runoff relations in the Klabava catchement
Kadeřábek, Michal ; Šobr, Miroslav (advisor) ; Kliment, Zdeněk (referee)
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...
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Seasonality of reproduction in tropical birds
Kačírek, Vojtěch ; Sedláček, Ondřej (advisor) ; Tomášek, Oldřich (referee)
The aim of of this paper is to summarize the knowledge of reproduction seasonality of tropical birds. Work includes characteristics of individual tropical environment and changes in abiotic conditions, focusing on the question, in what sense are tropics aseasonal and what is not. The work includes an overview of methodologies for collecting data during field research focused on monitoring reproduction in birds. The main part of this work is to compare the differences between biogeographic regions, regions and their stimuli, which most commonly lead to the creation of seasonal reproduction, followed by a comparison of individual functional groups of birds (food guilds). Powered by TCPDF (www.tcpdf.org)
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Evaluation of historical flood, Sázava River, 1909
Jelínková, Karolína ; Šobr, Miroslav (advisor) ; Kliment, Zdeněk (referee)
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
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Succession of insect communities inhabiting carcasses of small vertebrates, with emphasis on the beetles
Kadlec, Jakub ; Šípek, Petr (advisor) ; Růžička, Jan (referee)
This master thesis deals with succession and succession mechanisms of beetles (Coleoptera) on carrions of small vertebrates. As a model sample of small carrion a small mouse of weight 20 grams was chosen. In 2014 two experiments occurred. The first one studied the succession of a beetle community in dependence on seasonality and time of death of the sample. The second experiment was aimed to survey the blocking effect of an early insect succession on the final beetle community composition on carrions. It turned out, that during decomposition of the carrion the overall amount of beetles raised equally to the guild of necrophagous beetles. Change of the species spectrum during succession was not statistically confirmed. On the other hand, the effect of seasonality was clear as during the season the abundance and the amount of species increased. The proportion of trophic guilds changed significantly, necrophagous beetles were the most dominant part of the community towards the end of the season. Equally, the taxonomic composition of the community also changed during the season. The seasonal dynamics of carrion beetles was clear; Nicrophorus vespillo (Linnaeus, 1758) and N. investigator Zetterstedt, 1824 showed their peaks in spring and summer while N. humator (Gleditsch, 1767) and N. vespilloides...
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Disperzní a letová aktivita pakomárů stojatých vod (Diptera: Chironomidae)
VEBROVÁ, Lucie
I first review the significance of dispersal for individuals and populations including the role of the most significant environmental drivers on separate phases of dispersal. Emphasis is put on aquatic insects inhabiting small standing waters. The following manuscript summarizes a quantitative study of diel and seasonal flight patterns of adult Chironomidae in the Cep II sandpit in southern Bohemia. It provides one of the first comprehensive treatments of the effect of weather conditions and seasonality on the flight activity of adult Chironomidae, phenology of most common species and differences between terrestrial and aquatic species.
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Seasonal futures trading
Krupa, Michal ; Pfeifer, Lukáš (advisor) ; Štípek, Vladimír (referee)
This bachelor thesis deals with a topic of seasonal futures trading. It is seasonality which brings higher percentage success of trades and unlike the technical analysis it is based on fundamentals of the markets. Still it is not possible just to rely on the seasonal patterns, how it is shown in the practical part and it is necessary to filter these trades with another predetermined rules. This thesis brings complex view on commodity trading and discuss opportunity for income diversification in these unstable times. Finally, there is a mention how to use the concept of seasonality in another area of the national economy.
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