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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Struktura ptačích společenstev na výškovém gradientu Kamerunské hory / Bird assemblage structure on elevational gradient of Mt. Cameroon

Mudrová, Karolína January 2013 (has links)
Altitudinal gradients represent useful tool for investigating diversity patterns and processes affecting species richness and turnover along steep gradient of conditions at relatively small scale. The aim of my study was to compile a complete checklist of birds for elevational gradient of Mt. Cameroon rainforests (300 - 2300 m a.s.l.) and to analyse distribution of species diversity, species turnover, elevational ranges and relationships between elevational distribution of species and their range size, body weight or diet type. Species richness on the elevational gradient of Mt. Cameroon decline monotonically with some plateau at 600 - 1000 m a.s.l. Changes of community composition along the gradient are caused mainly by species turnover at low elevations, which contrast to pattern above 1200 m a.s.l. where the betadiversity is influenced mainly by continual species loss (nestedness). Species elevational ranges increase with increasing elevation, which is in agreement with elevational Rapoport's rule. Species breeding at higher elevations have smaller geographical ranges, restricted to isolated islands of montane rainforests. Numbers of insectivorous species are rapidly decreasing with increasing elevation, proportion of nectarivorous species is rather invariable and number of granivorous species...
12

Co určuje rozšíření trávníkových druhů na bývalých polích: struktura krajiny, podmínky prostředí, druhové vlastnosti nebo náhoda? / Landscape structure, habitat properties, species traits or chance: What determines distribution of grassland plants in abandoned fields?

Knappová, Jana January 2012 (has links)
Semi-natural grasslands are among the most threatened habitats in Europe, endangered mainly by cessation of former management practices and conversion into other types of land use. Extensive research has been carried out in European grasslands in last decades, to explain origins of diversity and to provide guidelines for its conservation. However, the very slow response of perennial plants to landscape changes often impedes to accurately evaluate why species occur just where they occur and not elsewhere. Abandoned fields are perceived as potential habitats for species from declining grasslands. Indeed, many species are able to spontaneously colonise abandoned fields, but many other species are absent from communities that develop there. An important question remains what limits their successful establishment. By answering this question, we can gain also important insights into factors determining species distribution in grasslands because colonization of recently abandoned fields by grassland species is the ongoing process which is not obscured by historical changes in landscape structure. The very basic aim of this thesis was to evaluate the status quo of dry grassland plants in fields abandoned in last two decades. And in the second step, to identify what are the main constrains of successful...
13

Dynamika druhů fragmentovaných suchých trávníků na úrovni krajiny / Dynamics of species of fragmented dry grasslands at the landscape scale

Hemrová, Lucie January 2013 (has links)
Past extensive changes in land use have resulted in fragmentation of species habitats. Changes in landscape structure have provoked discussion about the prospects of species of fragmented habitats in the future agricultural landscape. Landscape dynamics of plant species is basically a result of extinction and colonization rates. Many studies have confirmed the former expectation that a number of habitats suitable for a plant species in a landscape stay unoccupied. The differences in species distribution and proportion of suitable habitats occupied by a given species are hypothesized to be due to the area and isolation of suitable habitats and colonization and survival ability of a given species. To understand species dynamics in a changing landscape, first we have to reveal the relationships between the distribution of species and their proportion of occupied habitats, habitat age, habitat configuration and species colonization and survival ability. After the complete understanding of the determinants of species dynamics we will be able to predict reliably species prospect in the future. The very basic aim of this thesis was to reveal the determinants of landscape dynamics of dry grassland species in terms of their distribution and frequency in the landscape. The importance of correct identification...
14

Návrh managementu břehových porostů u vybraných vodních toků / Proposal of bank vegetation management at the selected streams.

ŠTĚPÁN, Vladimír January 2013 (has links)
My thesis deals with the collecting of basic information and data on riparian vegetation in surroundings of the minor watecourse Rosička through field research and subsequent inventory. In the theoretical part, I outlined the theme of watercourses and their modifications, revitalization and solutions. I also focused on vegetation accompaniment of the flows and their typology. I described the riparian and associated vegetation in detail, focused on their functions and establishment and on taking care of them. The final section of the thesis includes data of my field research. Here can be found the current condition of the species structure and the state of health of the riparian vegetation.
15

Lesní vegetace východního Polabí v polovině 20. století a dnes / Forest vegetation in Eastern Elbe Basin in the mid-20th century and today

Pospíšková, Marie January 2014 (has links)
This thesis describes the shift in vegetation of broadleaf forests in eastern part of the Elbe River Basin between 1958-1968 and 2011-2013. It emphasizes the understorey vegetation. From lowland woodlands in other temperate regions in Europe and North America changes towards eutrophic and mesophytic vegetation are documented, specifically driven by changes in forest management and by atmospheric depositions; in some localities the game impact can be also important. The data were obtained by sampling 190 typological semi-permanent plots, which were precisely located - in 43% the original soil pit was found. The vegetation on study sites shifted towards nutrient-demanding, shade- adapted species, it was partly ruderalized. These changes can be seen on the level of species and communities as well as on phytosociological level. Increase of soil pH and moisture was discovered using Ellenberg indicator values. The number of seedlings and cover of shrubs also increased significantly. Homogenization of sites was significant as well although total number of species and alpha- diversity remained unchanged. These changes are probably caused by changes in forest management and by atmospheric depositions of nitrogen. On subset of plots in game-preserves the vegetation also demonstrated eutrophication but no increase in...
16

Změny lesní vegetace Šumavy a jejího podhůří během druhé poloviny 20. století / Forest vegetation changes in the Bohemian Forest during the second half of 20th century

Prach, Jindřich January 2012 (has links)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
17

Změny vegetace vlhkých luk ve Slavkovském lese / Vegetation changes of wet meadows in Slavkovský les

Šimák, Martin January 2018 (has links)
This thesis focuses on the changes of vegetation of the wet meadows in Slavkovský Les during past decade. It uses data on vegetation gained from 100 permanent plots. By the analysis of the species composition and diversity it aims to elucidate the changes of the wet meadows over the last ten years. It aims to define, which are declining and which are becoming more common. Applied management should have a great impact on the observed vegetation changes so its effect is studied in the thesis as well. The knowledge of the suitable management should lead to conservation of the local biodiversity. The abiotic environmental factors are important as well as they can influence the species composition. These factors were studied by the application of Ellenberg indicator values on the species present in the study. These changes were compared in time and in a combination of time with a management type. Thus, we should be able to say how the environment has changed in the past decade and whether the type of management has any effect on the changes. Furthermore, the thesis explores whether changes in species composition over time may be explained by species traits. The results indicate that the species diversity and composition have indeed changed during the past decade. Apparently, the higher amount of...
18

Řízení nákladů v podniku / Cost Management in the Company

Yablonskyy, Yevhen January 2012 (has links)
The diploma thesis is focused on costs, calculation and primarily analysis of calculation systems and formula. The thesis is divided into two main parts – theoretical and practical part. The theoretical part is focused on explanation between financial and management accounting, description of basic terms and expense classification. Attention is given to system of calculation, its items, and calculation formula. Mention belongs to modern access of calculation – ABC. Practical part is focused on company Prefa Brno a.s., which main part of business is production and sale of building products and components. Shortly is mentioned characteristic of company, its history, present, sales and SWOT analysis. The main orientation of diploma thesis is on calculation system of the company, its descrtiption, methods of set-up and anylysis. Closing part of thesis includes summary of basic pieces of knowledge from analysis of calculation formula (system), which is compared with method of target casting, which belongs to modern methods of strategic management accounting. In the last part is given calculation in the case of additional item of material rate and quantification of impacts.
19

Druhová diverzita pastvin a luk na malé prostorové škále / Species diversity of meadows and pastures on small spatial scale

Bartoš, Michael January 2011 (has links)
Grazing seems to be not only means of conserving species diversity of grasslands but also - in many cases - of its increasing. This thesis tries to find out the mechanisms of grazing that result in increased or decreased species diversity. The experiment was proceeded in Slupenec, a part of Český Krumlov, where horse pastures are situated. In order to compare grazing and mowing I collected phytosociological data from plots 1 x 1 mš. I also collected data about soil moisture, composition and pH in order to find out the main gradients in vegetation. The vegetation data from plots 20 x 20 cmš were collected before and after grazing on three pasturelands. In the chosen locality, higher level of plant species diversity have been proven on pastures in comparison with meadows. There is significantly higher percentage of plots contributing to the higher level of ß diversity on pastures than on meadows. At the same time the variability of vegetation was in most cases explained by the categorial variable pasture / meadow. Concerning selectivity of grazing, it has been proven that horses prefer grazing on species with greater cover abundance. The plots with lower rate of grazed species have got higher ß diversity. In terms of functional traits of plants, it has been proven that higher percentage of no-rosette...
20

Analýza úrovně znalostí běžných druhů našich obratlovců u dětí z různých typů škol a zájmových uskupení / Analysis of knowledge level in common local vertebrate species at children from different school types and hobby groups

Švecová, Kateřina January 2013 (has links)
Analysis of knowledge level in common local vertebrate species at children from different school types and hobby groups This thesis deals with the research of practical knowledge and skills of students of primary and secondary schools. It targets exploring of cognition of local common species of vertebrates (fish, amphibians, reptiles, birds and mammals). It takes up this research (Lang, Pravda, 1971). It takes a large part of their methodology and compares the results with selec- ted reference species. The results are presented in graphs and chart tables. Key words: Knowledge of local vertebrates, questionnaire survey, primary school, secondary school, high school, hobby group, genus name, species name.

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