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Anatomical and physiological adaptations of high mountain plants in Ladakh
Binter, Jan ; Doležal, Jiří (advisor) ; Sklenář, Petr (referee)
The Ladakh region of the northwestern Indian Himalaya is a high-elevation desert that presents a suite of environmental conditions that constrain plant growth. At lower elevations, aridity and high temperatures constrain plant growth. However, at higher elevations, temperature steeply drops and an increase in precipitation occurs. Therefore, the Ladakh region can be considered a natural laboratory where the adaptive responses of plant traits to moisture and temperature gradients can be observed. Plants in high mountain regions had to evolve and adapt to harsh environmental stress including low temperatures, UV radiation, short growing seasons, etc. Morphological, anatomical and physiological adaptations allow plants in Ladakh to grow at altitudes up to 6150 meters. This limit for plant growth in Ladakh is not set by the permanent snow line or any other mechanical barrier, but instead by the inability of plants to survive at such an elevation. This situation allows us to study the physiological limits of plant adaptations in extreme conditions. Thus, studying plants in Ladakh can bring an important understanding to adaptive ability of mountain plants.
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Changes in ladybird communities along an altitudinal gradient
Matušová, Martina ; Kindlmann, Pavel (advisor) ; Martínková, Zdenka (referee)
Ladybugs are often used in biological control, because of their predatory way of life and potential ability to control many insect pests. So far, a number of studies was performed on this family, on their hunting strategies, other life history strategies, population dynamics, dependence of their distribution in time and space on the abundance of prey etc. However, the temporal changes in species composition and relative or absolute abundance of ladybugs were not yet examined along an altitudinal gradient. This is why I have focused my work on these dependencies. I tested the following hypothesis: overwintering sites in Coccinellidae are usually located at lower altitudes, where the individuals eventually attack their prey on the earliest budding trees; as season goes on, ladybugs follow the trends in environmental conditions and food and move to higher located sites; at the end of the season, ladybugs return back to their overwintering sites. In the research area in the Beskydy Mountains, 12 experimental sites were selected, evenly spaced along an elevational gradient of 350-482 m above sea level at each location. During the season, 12 measurements at two-week intervals were performed, each containing 2x300 sweeps. A total of 3064 of ladybug individuals were collected, belonging to 11 species. The...
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Diversity of bird species along elevational gradient on Cameroon mountains
Dubský, Marek ; Sedláček, Ondřej (advisor) ; Reif, Jiří (referee)
The aim of this thesis is to describe the changes of bird species diversity along elevation gradient on six mounts in Cameroon and nearby Bioko island. The results of the analyses confirm most of the defined hypotheses, especially they show that species diversity declines with altitude and rises with area. The absolutely highest diversity was detected on mount Kupé and mount Cameroon, but above 2100 m above sea level mounts Oku and Manenguba are the most diverse. Other analysis showed that the biggest changes in beta diversity of bird assemblages along altitudinal gradients are on the lowest elevational belts which are on the edges of a degraded habitats and continuous undisturbed forests. Other important changes in bird assemblages happen around altitude 1200 m, where the assemblages of lowland rainforest change to assemblages of mountain forest. Analyses of affinity of bird species to forest habitat showed that the most affined assemblages to the forest are those found on mounts Kupé and Rata. On the other hand bird assemblages on mounts Manenguba and Oku are the one of least affined to the forest biotope. Analysis of habitat generalism and specialism did not show the expected outcome and for clearer results the design of analysis needs to be improved. The results of this thesis contribute to a...
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Diversity and abundances of birds along altitudinal gradients of Cameroon Mountains
Dubský, Marek ; Sedláček, Ondřej (advisor) ; Reif, Jiří (referee)
The aim of this thesis is to describe the changes of bird species diversity along elevation gradient on six mounts in Cameroon and nearby Bioko island. The results of the analyses confirm most of the defined hypotheses, especially they show that species diversity declines with altitude and rises with area. Cluster analysis shows the similarity of individual mountains in particular altitude zones. Despite the original hypothesis, mount Cameroon is found to be most similar to mount Kupé, although high mountain assemblages of mount Cameroon and Bioko island are very alike as well. The absolutely highest diversity was detected on mount Cameroon and mount Kupé, but above 2100 m above sea level mounts Oku and Manenguba are the most diverse. The results of this thesis contribute to a clearer notion about factors influencing species diversity; however, more thorough data (particularly from mount Nlonako) and data extension for e.g. bird abundance would enrich the study and it would enable us to perform more detailed diversity analysis, especially an analysis of competition relationship among species. Key words Species diversity, Cameroon, bird assemblages, elevational gradient
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Fenologie lesních dřevin v měnících se podmínkách prostředí s ohledem na výškový gradient
Vránová, Kristýna
This thesis if focused to assessment of phenological characteristics of European beech (Fagus sylvatica L.) and European larch (Larix decidua Mill.). The observation was performed in two mixed forests of the same age situated at different altitudes 300 and 600 meters, respectively. Main meteorological variables were measured on both sites in order to describe the mezoclimate of the site. Observation of phenological phases was conducted in regular intervals twice a week. The results of the study confirm the strong dependence on both air and soil temperature. Collected data show the importance of temperature at the end of winter and early spring. Starting time of spring phenological phases depends on reaching of species specific temperature limits. The highest variability among individual years shows the time of beginning of budbreak. The temperature increase results in earlier beginning of spring phenological phases as well as shortening of their duration. For similar reason, also autumnal phenological phases are shifted towards the winter time. This fact causes longer vegetation period at the expense of winter dormancy.
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Changes in ladybird communities along an altitudinal gradient
Matušová, Martina ; Kindlmann, Pavel (advisor) ; Martínková, Zdenka (referee)
Ladybugs are often used in biological control, because of their predatory way of life and potential ability to control many insect pests. So far, a number of studies was performed on this family, on their hunting strategies, other life history strategies, population dynamics, dependence of their distribution in time and space on the abundance of prey etc. However, the temporal changes in species composition and relative or absolute abundance of ladybugs were not yet examined along an altitudinal gradient. This is why I have focused my work on these dependencies. I tested the following hypothesis: overwintering sites in Coccinellidae are usually located at lower altitudes, where the individuals eventually attack their prey on the earliest budding trees; as season goes on, ladybugs follow the trends in environmental conditions and food and move to higher located sites; at the end of the season, ladybugs return back to their overwintering sites. In the research area in the Beskydy Mountains, 12 experimental sites were selected, evenly spaced along an elevational gradient of 350-482 m above sea level at each location. During the season, 12 measurements at two-week intervals were performed, each containing 2x300 sweeps. A total of 3064 of ladybug individuals were collected, belonging to 11 species. The...
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The changes of species composition of soil phototropic microorganisms on the altitude gradient in E Ladakh
Janatková, Kateřina ; Němcová, Yvonne (advisor) ; Hrouzek, Pavel (referee)
Abundance and diversity of microbial phototrophic communities (cyanobacteria and eukaryotic microalgae) were investigated at two localities in main mountain ranges of Ladakh (Tibetan Plateau and Eastern Karakoram), India. Samples were collected along a two representative altitudinal gradients at each locality (E Karkoram 4620 - 5100 m asl., Tibetan Plateau 5346 - 5833 m asl.) in alpine and subnival zones in the vicinity of cushion plant Thylacospermum caespitosum (Caryophyllaceae). At each altitude 6 soil samples were taken from below cushion and 6 samples from outside the cushion. The epifluorescent microscopy and DGGE-method were used to determine diversity and biomass of phototrophs in the studied soils. Physico-chemical analyses (pH, texture, organic matter, nitrogen, ammonia and phosphorus content, concentration of chlorophylls and carotenoids) were also performed on the samples. The effect of altitude, mountain ranges and T. caespitosum on the composition and biomass of phototrophs and physico-chemical parameters of soil was tested by multivariate redundancy analysis and variance partitioning procedure. This study shows that the semiarid and arid soil of high elevation in Ladakh Mts. is suitable place for the development of microbial phototrophic communities and is important part of the ecosystem. The...
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Population structure and dispersal of butterflies in tropical rain forests of Papua New Guinea
VLAŠÁNEK, Petr
The thesis describes the community composition, population structure and dispersal in a lowland rainforest community, extended to changes in butterfly composition along an altitudinal gradient. It tests the feasibility of mark-release-recapture studies in the understories of lowland primary forests, describes dispersal in relation to host plants and compares dispersal and demographic parameters with temperate species. Focusing on primary as well as secondary sites the thesis analyzes species richness and similarity between sites along an altitudinal gradient. It also tests ecological correlates for endemism in New Guinea butterflies, particularly their geographic and altitudinal range, as well as their optimum altitude.
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Trophic relationships between insectivorous birds and insect in Papua New Guinea
TVARDÍKOVÁ, Kateřina
The thesis describes diversity of birds along a complete altitudinal gradient and in forest fragments in lowlands of Papua New Guinea. It focuses separately on the diversity of different feeding guilds, and discusses their links to habitat and food resources. More specifically, it focuses on forest insectivorous birds, their predation pressure on arthropods, feeding specializations and preferences, and some of the ways how insectivores search for food.
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Extrémní šířkové přírůsty smrku na gradientu nadmořské výšky na Šumavě a jejím podhůří
ČEJKOVÁ, Alžběta
Extreme radial growth reactions were analyzed over a 79-year period (1922-2000) to compare response of Norway spruce (Picea abies [L.] Karst.) along an altitudinal gradient (376-1221 m a.s.l.) in the Šumava Mountains, the Czech Republic. The comparison of the pointer years showed a specific pattern for altitudinal zones. Negative pointer years were usually induced by summer drought at low elevations and by wet-cold summer at high altitudinal zone. These two main limiting factors were probably combined at the middle altitudinal zone. Detailed understanding of the extreme tree ring pattern along the altitudinal and geographical scale may be used as one of the additional indicators of dendrochronological dating and provenance identification of spruce sample among altitudinal zones in the Šumava Mountains.
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