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The influence of environmental factors on amphibian assemblages
Kára, Martin ; Pivnička, Karel (advisor) ; Frouz, Jan (referee)
Like a large part of western Europe also from the Czech landscape is dramatically disappearing amphibians. This negative trend occurred due to several factors, some of which is undoubtedly the most significant loss of suitable breeding areas. During the years 2009 and 2010 I monitored a total of 31 tanks in a part of the former districts of Liberec, Jablonec nad Nisou and Semily, in which were multiplied frog (Rana temporaria) and toad (Bufo bufo). On these localities I've watched a few environment variables, which I assume that may affect the successful development of amphibians from egg stage to metamorphosis. The success of development, I determined by counting congeries in the spring and then finding the number of tadpoles in the tank survived the conversion. The results of multiple linear regression shows that the developmental stages of brown frog react negatively to the increasing altitude and increasing the number of eggs per unit area of the tank. On the contrary, they thrive better in larger, at least partially shaded tanks, which are subject to fluctuations in water level. For toad are suitable not very deep, partially shaded tanks, with a stable water level, vegetation and aquatic vegetation free shores. Also managed to find the eggs and tadpoles of toads react negatively to the...
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Population structure of the gray wolf (Canis lupus)
Říhová, Jana ; Hulva, Pavel (advisor) ; Pivnička, Karel (referee)
Gray wolf (Canis lupus), is historicaly the most widespread carnivore with the former range including most of the northern hemisphere. The ambivalent relationship of humans to this predator resulted in extermination of this species in many areas, on the other hand led to the evolution of the dog, unique domesticant with vast phenotypic variation. The effort of conservation biology in last decades resulted in the shift of perception the role of big carnivores in ecosystems, with consequent recolonization of many regions by wolf, including the Czech republic. This changes brings the elevation of interest in this taxon by both experts and laymans. Present review aims to assemble published information regarding distribution, phylogeography, population structure, social and spatial behaviour of the gray wolf. The chapters describing the domestication process of the dog and hybridization with his wild ancestor are included.
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Basis for conservation assessment of Plant diversity of dry basic habitats within the forest environment in the Doksy region
Martinec, Pavel ; Sádlo, Jiří (advisor) ; Pivnička, Karel (referee)
Theme: Basis for conservation assessment of Plant diversity of dry basic habitats within the forest environment in the Doksy region Abstract: The subject of present study is high species richness of vascular plants on localities of dry basic habitats in Doksy region. This habitats are enclosed by nutrients poor habitats of coniferous forests, restricted to small areas and spatially isolated. The dry basic habitats represent high valuable areas for nature conservation due to high α-diversity and occurence of rare plant species with scarce populations within flora of Czech Republic. The aim of study is to collect and review known data about dry basic habitats of Doksy region and their biodiversity. Consequently find optimal approaches in analysis of biodiversity and approach in interpretation for nature conservation. Actual status of flora and vegetation depend on environmental factors, biotic interaction, evolution and historic development. The perspective theoretical approach in species diversity analysis shows the species-pool hypothesis (Taylor et al. 1990) which assorts and describes these factors. Keywords: biodivesity, vascular plants, Doksy region, species-pool hypothesis, nature conservation
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Management of the protected areas in sand habitats
Šímová, Kamila ; Münzbergová, Zuzana (advisor) ; Pivnička, Karel (referee)
Management of the protected areas in sand habitats is a thesis interested in the management techniques in relation to the sand habitats. In Central Europe, sand habitats are a rare and threatened grassland biotope. In the Czech Republic, we can find natural sand habitats localities, which are threatened by the human impact and anthropogenic localities, which tend to increase in number. Diversity and richness of the natural stands is gradually decreasing due to the high sensitivity of the species to any change of the local environment. These changes are mainly caused by the human activity. The negative effects are eutrophication, acidification and accelerated succession. The management of the sand habitats should contain many succession regulation tools and techniques reducing eutrophication. I discuss mowing, removal of the expansive plant species, pasturage, burning and sod disturbance or sod cutting. Each of these methods has specific impacts on the ecosystems and the best management combines them to achieve the best performance of the protected area. The most preferable method seems to be sod cutting, due to its high effectivity. However, there are many questions about sod cutting that need to be answered in a future study, such as how the population dynamics after sod cutting will look like, what the...
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The use of otoliths for growth and population dynamics studies of Percidae and Cyprinidae in Most water reservoir
Tůmová, Eliška ; Frouzová, Jaroslava (advisor) ; Pivnička, Karel (referee)
This Master thesis compares growth of Percidae and Cyprinidae in flooded mining pit Most with water reservoir Vír, which is stable, fifty years old. Fish were cought using toils by workers from Hydrobiology institute, Academy of Sciences, Czech Republic, which are exploring fish stock. Otoliths, scales, and operculas from both families, Cyrinidae and Percidae, were removed from fish for age determination and growth back-calculation in individual years. Due to surplus of nutrients and food in flooding mining pit is assumed a huge growth difference in the first two years of life. The aim of this thesis is not only to describe the difference in the expected growth of individual species, but also to estimate its causes. At the same time will be in a very contrasting conditions compared different methods of age determination. Key words: otolith, fish age, fish population, fish growth, water reservoir, flooded mining pit, growth back-calculations
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Insects as human food
Augustinová, Šárka ; Frouz, Jan (advisor) ; Pivnička, Karel (referee)
Insects as a traditional source of food widespread in tropical and subtropical regions offer significant nutritional, economical and ecological gains not only to rural communities. Western bias against insects led to gradual reduction of usage of insects as food without any compensation for lost sources of nutrition and other benefits. Current efforts of the Western world to prevent starvation of population and undo the consequences of inconsiderate human interventions into the environment are often futile and ineffective. One of possible answers to these global problems could be reestablishment of insects as a food source for the native population. Insects offer a renewable source of protein with nutritional values as high as 3186kJ per 100g of solids which exceeds the values of most species traditionally cultivated. The protein content varies throughout the various insect species from 30% in wood-worms to 81% in wasps of the genus Polybia. Moreover, the quality of these proteins is very high and the high values of the amino acids contained outperform the FAO recommended designs. Many species contain important minerals such as calcium, sulfur, iron, phosphor, magnesium and zinc and are as well rich in B vitamins, niacin, riboflavin and thiamin, which are often not incorporated enough into standard meal...
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