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Drivers of avian diversity on an altitudinal gradient of Mount Cameroon
Djomo Nana, Eric ; Hořák, David (advisor) ; Šálek, Miroslav (referee) ; Waltert, Matthias (referee)
Altitudinal gradients constitute a powerful test system for understanding distribution of species around the globe. Tropical mountains are quite rich in species even after controlling for environmental productivity, and are ideally suited for studying patterns of species distributions because they have had sufficient time for species to produce a response to environmental changes that affect their life histories. In this thesis, I investigate basic ecological mechanisms potentially behind avian distribution patterns along an altitudinal gradient in West-Central Africa. I used data collected with four methodological approaches (point counts, mist netting, random walks and artificial nest experiments) along an altitudinal gradient on Mt. Cameroon from October 2011 to September 2013. This work is focused on two interrelated themes: selection pressures on life histories (Chapters 1, 2, 3 & 4), and avian assemblage structures (Chapters 5 & 6). In the General Introduction, I present an overview of the study area with conservation implications of the study and my study objectives. In Chapters 1, 2 & 3, I investigate how selection pressures, i.e., nest predation and parasitism by haematozoa, affect bird assemblages. I used artificial nest experiments to assess nest predation rates in Chapters 1 & 2, and my...
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Aspects of the movement in the alpine environment, with emphasis on altitude sickness
Szotkowská, Lucie ; Kašpar, Ladislav (advisor) ; Pokorný, Ladislav (referee)
This thesis is focused on aspects of mountains activities as a ski touring, hiking and mountaineering. This field of sports are associated with the risk of altitude sickness. The thesis examines key parameters that contribute to the emergence of altitude sickness. The other examinees parameters are weather conditions, influence of high altitude, physical training and physiological manifestations of individual person. The aim of this thesis was find out which sports are the most affected by high altitude sickness. And what are the most common symptoms of altitude sickness. It was based on the literature and questionnaire.
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Lipid composition of biological membranes and life-histories in songbirds
Šimonová, Kateřina ; Tomášek, Oldřich (advisor) ; Sam, Kateřina (referee)
Differences in the composition of cell membranes are considered to be the physiological mechanism responsible for different metabolic rates, life span and consequently, different life-histories. The membrane pacemaker theory suggests that higher membrane unsaturation may be an important factor responsible for higher metabolic rate and shorter life span of organisms. The alternative hypothesis, on the other hand, assumes that membranes can function as structural antioxidants, and thus that higher membrane unsaturation may be associated with longer life span. The aim of this work was to test how changes in the fatty acid composition of membranes depends on body size, latitude and altitude, within which different life-histories and metabolic rate were observed. Temperate and tropical lowland songbird species were chosen for the models testing the effect of latitude, and only tropical species of songbirds were chosen for the models testing the effect of altitude. Part of the work was molecular sex determination. Using gas chromatography and mass spectrometry, the amount of individual fatty acids contained in red blood cell phospholipids was obtained from blood samples. The results showed that the composition of the membranes in most cases correlates with body size, which also correlates with almost all...
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The altitudinal dependence of long-term surface air temperature changes
Krauskopf, Tomáš ; Huth, Radan (advisor) ; Pokorná, Lucie (referee)
The altitudinal dependence of long-term surface air temperature changes Abstract In this work there is summarized the scientific literature which is focused on the spatial distribution of long-term surface air temperature changes, specifically on the altitudinal dependence of warming rate. In this text this dependence is analyzed both globally and in several major mountain regions. The greatest attention is paid to the Swiss Alps, where is the largest network of weather stations and there should be achieved reliable results. Furthermore, this work refers to mechanisms that cause different rates of warming at different altitudes, such as snow-albedo feedback or changes in the frequency of fog and cloud. The aim of the practical part is then to analyze surface temperature trends in the Czech Republic and to assess the altitudinal dependence of long-term surface air temperature changes in our country. Keywords: climate change, temperature, trends, altitude
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Climatic determinates of elevation ranges in tropical vertebrates
Vobořilová, Kateřina ; Hořák, David (advisor) ; Šmíd, Jiří (referee)
Tropical regions are amongst the most diverse ecosystems on Earth. The significant species richness of these ecosystems is evident in the number of vertebrate species due to their distribution along altitudinal gradients. The distribution of vertebrates throughout altitudinal gradients is a natural phenomenon by which vertebrates respond to diverse abiotic conditions. Together with the geographic distribution of mountains, biotic influences, thermal physiology of individual vertebrate groups or climatic changes, these abiotic conditions create specific conditions for vertebrates. All of these factors may contribute to the spread of vertebrates to lower or higher altitudes. They may also influence altitudinal migration, depending on the adaptation of individual vertebrate species. In this thesis I focused on how individual abiotic determinants such as temperature, precipitation and air humidity, as well as climatic changes, can positively or negatively influence the distribution ranges of four vertebrate groups along elevational gradients of tropical mountains. Keywords: temperature, precipitation, cloudiness, tropics, elevation, geographical distribution, species richness
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Relationship between the UV index and selected parameters
Tomanová, Helena ; Pokorná, Lucie (advisor) ; Metelka, Ladislav (referee)
Relationship between the UV index and selected parameters Abstract Ultraviolet radiation (UV radiation) is a shortwave radiation with wavelengths from 100 to 400 nm. This radiation has both positive and negative effects on living organisms and human health. Therefor the so-called UV index (UVI), characterizing the biological effect of UV radiation on human health was defined in 1994. This thesis aims to evaluate the link between selected factors (total ozone column, solar elevation angel, cloudiness and altitude) and the UVI values. Observed data at four stations in Czechia (Hradec Králové, Košetice, Kuchařovice, Labská bouda) and SYNOP reports from the four nearest stations during the period 2010−2017 were used. The Sun elevation (angle of Sun ray) has the strongest effect on the UVI values. The highest UVI values are generally reached at high angels when the Sun rays go the shortest path through the atmosphere. The increase of the UVI is exponential, from an angle of 30ř the increase is approximately linear. The UVI values increase on average by 0.8 at the Hradec Králové station and by 0.9 at the Labská bouda station for angle increasing by 5ř. The effect of clouds is significant and depends on the height and the clouds amount. High level clouds reduce UVI negligible, overcast sky by only 15 %. Medium and...
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Lipid composition of biological membranes and life-histories in songbirds
Šimonová, Kateřina ; Tomášek, Oldřich (advisor) ; Sam, Kateřina (referee)
Differences in the composition of cell membranes are considered to be the physiological mechanism responsible for different metabolic rates, life span and consequently, different life-histories. The membrane pacemaker theory suggests that higher membrane unsaturation may be an important factor responsible for higher metabolic rate and shorter life span of organisms. The alternative hypothesis, on the other hand, assumes that membranes can function as structural antioxidants, and thus that higher membrane unsaturation may be associated with longer life span. The aim of this work was to test how changes in the fatty acid composition of membranes depends on body size, latitude and altitude, within which different life-histories and metabolic rate were observed. Temperate and tropical lowland songbird species were chosen for the models testing the effect of latitude, and only tropical species of songbirds were chosen for the models testing the effect of altitude. Part of the work was molecular sex determination. Using gas chromatography and mass spectrometry, the amount of individual fatty acids contained in red blood cell phospholipids was obtained from blood samples. The results showed that the composition of the membranes in most cases correlates with body size, which also correlates with almost all...
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Hodnocení ekologických limitů a zdravotního stavu hlavních edifikátorů lesních ekosystémů v oblasti Králického Sněžníku
Šmída, Jiří
The thesis deals with the valorization of ecological limits and health status of Norway spruce (Picea abies), European beech (Fagus sylvatica), sycamore maple (Acer pseudoplatanus) and silver fir (Abies alba) in old forest stands on research plots in the Králický Sněžník Mountains from 4th to 9th vegetation tier. Results are aggregate data, which demonstrate ecological limits for individual tree species. In higher altitudes, the blemishes of strains are more common. The average heights of trees are at higher altitudes lower. Norway spruce can be found in all vegetation tiers and its production optimum is from 4th to 6th VT. The average height of European beech is 30 meters in 4th, 5th and 6th VT. In the 7th VT European beech occurs overtopped level only, because of harsher climate and short growing season. Sycamore maple has an ecological optimum in the 5th VT. Silver fir occurs in forest stands, in 4th VT only.
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Bird Communities Along the Altitudinal Gradient on Mt. Cameroon: Perspectives from Mist Nets
Petruf, Miroslav ; Sedláček, Ondřej (advisor) ; Lučan, Radek (referee)
in English Mt. Cameroon is a hotspot of diversity and endemism in Africa. Recent research of avian bird communities along the elevational gradient on Mt. Cameroon based on point counts has shown low-elevation plateau of species richness. At the same time, range-restricted montane populations of birds on Mt. Cameroon are unusually abundant if compared to lowland species. I analysed data on community composition, species richness and abundance of birds using an alternative quantitative method - 200 m of understory mist nets erected for three consecutive days across seven elevational plots along the forested gradient of the Mt. Cameroon. First, I looked at the technical limits of this method and confirmed the general opinion that they are better at detecting small birds below 33 g, and that they mostly detected fewer individuals after the first day and always detected fewer new species after the first day of mist-netting. Mist nets detected high proportions of ground-feeding and understory birds and low proportions of birds foraging in higher strata in the lowland forest, which has a scarce understory and a dense canopy. Mist nets recorded similar proportions of birds foraging in all forest strata in the vastly open mid-elevation forest, which has a dense herbaceous understory. They detected higher...
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