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Abrupt cooling events in the Late Glacial and the Early Holocene
Švanda, Petr ; Vondrák, Daniel (advisor) ; Tichá, Anna (referee)
This bachelor thesis is prepared in the form of a literature review focused on abrupt cooling events in the Late Glacial Interstadial and the Early Holocene (14 700 to 8 200 cal. BP). The aim was to summarize the scientific knowledge on six such climate fluctuations and their causes and consequences. All of these events (GI-1d, GI-1c2, GI-1b, 11 400 event, 9 300 evenet, 8 200 event) lasted more than 50 years and are followed by cooling of more than 1 řC. Literature sources on this topic are based on interdisciplinary studies of various natural archives and the interpretation of so-called proxy data. For each climatic event, an assessment of its effects on ecosystems and human societies at the time was also made. The above findings are finally discussed in the context of the current climate change issues and the possible future of weakening the Atlantic Meridional Overturnig Circulation.
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Citizen science as a tool for monitoring phenological changes in our reptiles
ONDŘEJKOVÁ, Pavlína
The diploma thesis deals with the length of seasonal activity of reptiles in Czech republic and follows their phenological shift in response to temperature changes. The first part of the thesis is devoted to the factors influencing the reptiles' occurrence, phenology, and the importance of citizen science and its possible con-nection with data collection. The second part includes monitoring results regarding the length of activity of individual species over the years and their shift in the be-ginning and end of activity. All species show a lengthening of the season - to ear-lier dates of their first appearance in spring and enter hibernation later. The largest difference in the shift of the beginning and end of the activity was shown by the Eastern slowworm (Anguis colchica). The least significant extension of activity towards the beginning of the year was shown by the Grass snake (Natrix natrix) and towards the end of the year the European pond turtle (Emys orbicularis). Records of reptile sightings were obtained from the Nature Conservation Discovery Database.
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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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Niche width of eukaryotic marine phytoplankton with respect to recent and future climate change.
Junková, Natálie ; Kulichová, Jana (advisor) ; Neustupa, Jiří (referee)
This paper describes the concept of niche breadth of photoautotrophic protists and attempts to introduce us to the basic concepts we may encounter when studying the ecological niche. The review clarifies what a niche is and its components fundamental and realized niche and presents some examples of organisms that are specialists or generalists. It uses diatoms, dinoflagellates and Haptophytes to describe how they can be affected by climate change. Since the number of environmental changes is steadily increasing, it is very difficult to predict the changes in the coexistence of generalists and specialists. The thesis presents some of the main methods used in measuring the width of the ecological niche of protists, which can be MaxEnt, ONE and the most frequently mentioned OMI (outlying mean index) method, which is described in more detail in the thesis. Given the focus of the thesis on photoautotrophic marine plankton, the most frequently mentioned organisms are diatoms, dinoflagellates and Haptophyta. Finally, I summarize the main ocean factors that could be affected by climate change, which are mainly pH, temperature, salinity or the amount of available nutrients (carbon, nitrogen, phosphorus, silicon and iron).
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Quo Vaditis Agriculture, Forestry and Society under Global Change? From understanding past and present Earth´s processes to adaptations for the future
Šprtová, Miroslava ; Bartošová, Lenka ; Acosta, Manuel ; Klem, Karel ; Leventon, Julia ; Červený, Jan
International conference „Quo vaditis agriculture, forestry and society under Global Change? From understanding past and present Earth’s processes to adaptations for the future“, whose scientific sponsor is the European Center of Excellence CzechGlobe, should prove that science has an irreplaceable role in addressing mitigation and adaptation to climate change, in meeting international commitments to climate change and tasks of the EU Strategy on adaptation to climate change.
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The effect of temperature on plant growth: teaching protocols of model experiments
Máhrlová, Zuzana ; Albrechtová, Jana (advisor) ; Mourek, Jan (referee)
This diploma thesis is focused on the creation of model tasks (by means of an experiment) for the study of biology at secondary schools and concerns the effects of temperature on plant growth. The selected tasks utilize the new didactic approach by means of the so called inquiry based education. This method of teaching contributes to the development of individual deduction reasoning and encourages the students to actively think about the subject matter. The thesis provides the necessary theoretical background for the topic together with the description of methods and material needed for the conducting the experiments. Furthermore, the thesis describes the necessary instructions and procedures to conduct the experiment and its use in the secondary school teaching practice and presents the requisite methodical guidelines and worksheets for them. Simultaneously, the thesis verifies the didactic applicability of the experiment and the worked out materials through a questionnaire survey and monitored application of the model tasks at secondary schools. The main result of this diploma thesis is a modern, functional and verified method of teaching for high school about the effects of temperature on plant growth in accordance with modern approaches to education, which include own experiments, their...
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Impact of volcanic activity on environment and climatic conditions during geological history of the České středohoří Mts.
Zajícová, Jana ; Kvaček, Zlatko (advisor) ; Teodoridis, Vasilis (referee)
The influence of volcanoes on climate is very often debated, not only in the scientific community. However, the question remains, how much may the volcanic activity contribute to the significant ganges, that could cause a response of environment, which lies in the immediate vicinity. These changes could arise as a response on prolonged exposure of the negative influence, which would last much longer than decades, like it is at present. From this reason the situation in the České středohoří Mountains, where the volcanic activity lasted for several million years during the Paleogene period, is studied. This area is extraordinally rich in deposits of so-called volcanic floras, which accompany the neovolcanic activity. The age of the localities are between late Eocene to late Oligocene and it is a long time enough for recognizing some changes in the floristic composition to help elucidate the given problem.
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The effect of climate change and land use change on the long-term population trends of birds in the Czech Republic
Koschová, Michaela ; Reif, Jiří (advisor) ; Voříšek, Petr (referee)
There are number of future projections of species' geographic ranges developed under conditions of ongoing climate change. However, only a few studies have assessed what are the characteristics of species explaining interspecific variability in the projected range shifts. Examination of such relationships is important for development of effective conservation strategies mitigating the effects of climatic changes. For this purpose, I calculated the predicted shifts of European ranges in Czech birds based on maps in A Climatic Atlas of European Breeding Birds and explored relationships between these predicted shifts and several ecological traits. We found significant effects of the type of European distribution and habitat requirements. Concerning the type of European distribution, the largest shift is predicted in the central species and the northern species compared to widespread and southern species. According to the habitat type, the largest shift showed forest birds in contrast to the urban species which will shift slightly. The former pattern is probably attributable to spatial constrains different among these specific groups (central species are less limited compared to widespread species). The latter pattern could be explained by higher sensitivity of forest species to climatic changes...
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Development of the mammal assemblages during Quaternary climatic changes
Havlová, Tereza ; Mazuch, Martin (advisor) ; Nývltová Fišáková, Miriam (referee)
During the Quaternary there was a cyclical alternation of warm and cold periods - interglacials and glacials. Over the past 2.5 million years there was eighteen or twenty these cycles. These climate changes influenced by, except other, Milankovic cycles caused at sea level, extent of glaciation or distribution of vegetation zones. All these factors affected the communities of mammals, their distribution, migration and extinction of some groups of mammals. Area of continental and mountain glaciers expanded as well as levels of the ocean decreased during the glacials. Many species of mammals penetrated into new territory with the emergence of land-bridges a mammals from isolated areas could interact during cold periods. There was a retreat of glaciers and sea level rise and the migration routes through the land bridges was interrupted during the interglacials. Many, mostly island, populations were isolated and they were often developed to new endemic species. Key words: glacial, interglacial, climate changes, distribution, migration, extinction
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Long-term changes in winter and spring runoff in mountain catchments in Czechia
Klinkovská, Simona ; Jeníček, Michal (advisor) ; Vlach, Vojtěch (referee)
Climate changes occurring on Earth influence most of the natural processes. This also includes snow storages which have been decreasing in many mountain regions over the last decades. Besides increasing air temperature, changes in snowfall fraction, snow storages and snowpack duration also occur. For snow dominated mountain catchments, runoff timing from snowmelt is essential. Due to air temperature increase, runoff occurs earlier. Additionally, evapotranspiration increases as well. This thesis summarizes current knowledge regarding snowpack and runoff changes in mountain catchments. It further analyzes changes in 14 Czech mountain catchments over a 50-year period (1965-2014) using a Mann-Kendall trend test which identifies trends in selected time series. The trend analysis was followed by quantification of trends using Sen's slope estimator. The results showed that the day of 50% of total annual runoff occurred earlier in all catchments. Increased winter runoff was found in the Krkonoše catchments. Significant and extensive negative trends were detected in May for most of the catchments. There were almost no significant trends detected in the Beskydy catchments. Key words: snow, snowmelt runoff, trends, climate changes
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