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Reakce sazenic břízy bělokoré (Betula pendula Roth.) na stres suchem
Orlovský, Vít
Climate change, with its accelerating intensity, is the primary factor to which forest and urban stands need to respond. Particularly more frequently, recurrent periods of drought, coupled with rising average annual temperatures, mainly in urban development, represent a significant plant stressor. As silver birch (Betula Pendula Roth) is a frequently used tree in urban plantings, the aim of this work was to assess the physiological response of silver birch seedlings after the completed leaf development to stress by drought. Evaluation of the response of the seedlings to stress confirmed the assumption that water potential decreases as the drought increases. Due to the stress of the drought, we saw an 86% decrease in water potential measured at noon compared to the beginning of the experiment. From the results of a 17-day experiment, we found that stress from drought caused a 96% decrease in the rate of photosynthesis and stomatal conductance. So birch seedlings reacted very sensitively to drought stress by trying to avoid reducing water potential. When comparing the variability of the responses of individual seedlings, the physiological parameters showed a marked difference in their response to stress by drought. For example, for rate of photosynthesis, the coefficient of variation for stressed seedlings reached 97% at the end of the experiment. The PRI reflectance index, which indirectly characterises the carotenoid content, showed a coefficient of variation of even 306%. All this information provides us with clear evidence of the ability of individual birch seedlings to react to drought stress in a different way. Based on our measurements and subsequent results, we can conclude that the variability of silver birch seed material is able to respond to the demands implied by the projected climate change.
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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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Plant adaptation to climate change
Koláříková, Veronika ; Münzbergová, Zuzana (advisor) ; Sklenář, Petr (referee)
Climate change represents important selective force for plants. They have to deal with this change otherwise they are facing the risk of extinction. Understanding the mechanism which plants use to avoid the risk is essential for effective conservation of biodiversity. The climate change can exceed the tolerance of plants to abiotic factors. The plants can react to the changes by migration, phenotypic plasticity, evolutionary adaption or by a combination of these strategies. Phenotypic plasticity and evolutionary adaption are manifested by a change of physiology, morphology and/or phenology of plants. This work summarizes the findings of these ecological and evolutionary strategies and also presents methods used for studying species response to climate change. Powered by TCPDF (www.tcpdf.org)
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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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Representation of the problem of climate change in the print media
Trunečková, Daniela ; Novák, Arnošt (advisor) ; Hájek, Roman (referee)
This diploma thesis on Representation of the problem of climate change in the print media is a content analysis of Czech quality daily newspapers, namely Hospodářské noviny, Lidové noviny, Mladá fronta DNES and Právo. It deals with the way the selected daily newspapers presented debate on global climate change in 2013-2014. The theoretical part informs readers about the basic concepts and definitions and introduces them to the problem. The empirical part answers the question of whether the media coverage of global climate change in Czech quality daily newspapers is consistent with scientific findings of the international climate discourse represented by Intergovernmental Panel on Climate Change (IPCC) or whether it relies equally on opinions of the small group of so called climate skeptics who question the general consensus of the scientific comunity regarding the causes and consequences of climate change or the need of adequate measures. The results of research indicated that most of analyzed articles informed about climate change the same way as the main climatological research. The largest number of skeptical articles appeared in Lidové noviny. A considerable number of articles didn't comment on the causes of climate change, their seriousness or decisions regarding action.
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Alpine glaciers retreat after little ice age and its relation to climate changes
Dutková, Alena ; Sládek, Ivan (advisor) ; Zelenka, Přemysl (referee)
This thesis deals with climatic changes and its influence on mountain glaciers in Alps since the little ice age to present. Knowledge published in domestic and foreign literature is applied to the example of Morteratsch glacier in swiss Alps and high elevation meteorological station Sonnblick in austrian Alps. Alpine mountain range is one of the most researched and the longest populated mountain ranges in the world. For this reasons we have for use long time period of meteorological and glaciological datasets.
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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 use of diatoms (Bacillariophyta) in paleolimnology
Aubrechtová, Martina ; Kulichová, Jana (advisor) ; Píšková, Anna (referee)
This thesis is a literature review summarizing methodology and the possibility of use of diatoms (Bacillariophyta) for paleoecological reconstructions of extinct lacustrine ecosystems. In addition, the theoretical part of the thesis is devoted to basic characteristics, evolutionary history and ecology of the group, lakes and the fossil record. In the practical part, two samples of sediments of a fossil lake that has been discovered and studied within the Morava Project in Strážnické Pomoraví are compared.
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Winter teritoriality im passerines in relation to environmental and climatic conditions
Glückseligová, Pavla ; Musil, Petr (advisor) ; Reif, Jiří (referee)
This thesis is focused on winter territoriality of passerines. It summarizes general knowledge of territories, territorial behaviour and broader knowledge about winter territoriality. Winter social behaviour of individual species, their territoriality, migratory strategy and food preferences were summarized for Western Palearctic bird species. Furthermore, effect of climate change on passerines and their migratory behaviour, timing of breeding and their relationship to food abundance and conspecific competition. In the last chapter, there is discussed effect of climate change on species displaying wintering territoriality. Increasing temperature can affect food availability, competition for sources and consequently reproduction success.
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