National Repository of Grey Literature 10 records found  Search took 0.00 seconds. 
Species-area relationship in birds: variation across temperate zone environments
Gaigr, Matěj ; Hořák, David (advisor) ; Hanzelka, Jan (referee)
The relationship between area and number of species is one of the oldest and most studied principles in ecology, often referred to as one of the laws of ecology. Ecologists use it primarily to model the expected number of species in a given area. The Species-Area Relationship (SAR) states that the larger the area being, the greater the number of species present. However, area is not the only factor influencing species diversity - habitat heterogeneity is also a frequently studied factor affecting species richness. The number of species in an area tends to be positively influenced by heterogeneity since factors that are positively correlated with heterogeneity have a large influence. These factors include the species diversity of vegetation, the level of energy productivity, the number of microhabitats, the effect of disturbance or the amount of different food sources. Individual temperate habitats differ in the relative contribution of heterogeneity in its impact on observed species abundance. Species abundance is not only influenced by habitat heterogeneity, but also by other factors such as altitude, climate or latitude. The most affected habitats regarding the relative contribution of heterogenity are forest environments. Vertical diversity is the main influence causing high heterogeneity in...
Bird conservation status along a successional gradient in abandoned military areas
Bystřický, Václav ; Reif, Jiří (advisor) ; Hořák, David (referee)
Populations of open habitat bird species has significantly decreased in the Czech Republic during the last decades due to a number of negative factors, such as urbanization and intensification of agriculture. Due to the deterioration of the quality of these biotopes, a number of bird species (not only those of conservation importance) were forced to look for remaining fragments of favorable habitats, which are, for example, abandoned military training areas. The attractiveness of these territories lies primarily in their former closure for military purposes, which has protected these areas against these negative factors. In addition, army's activities created a heterogeneous landscape characterized by a mosaic of biotopes in different stages of vegetation succession - from bare ground, through grasslands, sparse scrubland, dense scrubland to the forest. However, the significance of abandoned military training areas for birds requires deeper investigation. The main goal of this thesis was to describe conservation importance of bird communities in individual biotopes along the successional gradient, for which a survey of 42 abandoned military training areas was used. The results of my work show that the most declining, endangered and protected species of birds sought out early successional habitats...
Synthesis of digital landscape surface data
Šebesta, Michal ; Kahoun, Martin (advisor) ; Křivánek, Jaroslav (referee)
A procedural generation of landscapes often meets a need for real spatial data at finer resolution that data available at the moment. We introduce a method that refines the spatial data at the coarse resolution into the finer resolution utilizing other data sources which are already at the better resolution. We construct weighted local linear statistical models from both the coarse and utility data and use the by- models-learned dependencies between the data sources to predict the needed data at better resolution. To achieve higher computational speed and evade utility data imperfection, we utilize truncated singular value decomposition which reduce a dimensionality of the data space we work with. The~method is highly modifiable and its application shows plausible real-like results. Thanks to this, the method can be of practical use for simulation software development. Powered by TCPDF (www.tcpdf.org)
Využití mapování biotopů pro stanovení ochranářského potenciálu těžeben: vegetační pohled
SLABA, Michal
A geographic information system (GIS) provided framework for gathering and analysing of large dataset comprising all available recent mining sites in the Czech Republic. Biotope mapping was used as a main tool for prediction of conservation potential of mining sites. The proportion, type (natural vs modified by human, woodland vs non-woodland) and distance of biotopes up to 1 km distance from the edge of mining site have been evaluated. The information obtained from various maps was combined with relevés from selected mining sites (at least four relevés per locality) summarized in Database of Successional Series. Participation of target (i.e. grassland, woodland, wetland), and synanthropic species in relevés was calculated for each sampled locality. The results proved that only the distance to non-woodland biotopes up to 21 m from the edge of disturbed site had significant effect on participation of target species in the mining sites. Localities, where proportion of target species exceeded 50 %, were considered as perspective for nature conservation. The effectivity of this new method was verified on another dataset (less than 4 relevés per locality) and reached almost 70 %. This new approach can help with preliminary identification of localities with conservation potential but vegetation survey should be kept as integral part of each ecological restoration as effectivity of proposed method varied also among particular post-mining sites.
Synthesis of digital landscape surface data
Šebesta, Michal ; Kahoun, Martin (advisor) ; Křivánek, Jaroslav (referee)
A procedural generation of landscapes often meets a need for real spatial data at finer resolution that data available at the moment. We introduce a method that refines the spatial data at the coarse resolution into the finer resolution utilizing other data sources which are already at the better resolution. We construct weighted local linear statistical models from both the coarse and utility data and use the by- models-learned dependencies between the data sources to predict the needed data at better resolution. To achieve higher computational speed and evade utility data imperfection, we utilize truncated singular value decomposition which reduce a dimensionality of the data space we work with. The~method is highly modifiable and its application shows plausible real-like results. Thanks to this, the method can be of practical use for simulation software development. Powered by TCPDF (www.tcpdf.org)
Mating systems and ecological correlates in family Rallidae
VRÁNA, Jakub
Correlation among ecological factors and mating systems of Rallidae was analysed. Tested factors included: sociality, fligthless, sexual dimorphism in colouration, sexual dimorphism in weight, occurrence in aquatic and semiaquatic biotopes and occurrence in terrestrial biotopes. Data was obtained from articles and books.
Characteristic of brook lamprey \kur{(Lampetra planeri)} habitats in the Malše River catchment
HLAVÍNOVÁ, Lenka
The aim of the present diploma thesis was to prove the habitation of brook lamprey near Dolní Dvořiště. Biotopes with habitat preferences of brook lamprey were described. During the ichtological investigation of the catchment area of the Malše river in the years 2007 - 2008, brook lamprey was successfully located on sites in Dolní Dvořiště and near Všeměřický quarry. The sites had the same character as trout streams. Length -frequency distribution of the brook lamprey larvae was executed. The species assemblage of ichtofauna of the sites with brook lamprey habitation was described. In the years 2008-2009 other possible biotopes were mapped in connection to the sites in Malše and Tichá where brook lamprey had been located before.
Evaluation of vegetation remnants of former settlements in selected border areas
KALNÁ, Eva
Eva Kalná, 2010:Evaluation of vegetation remnants of former settlements in selected border areas. It was chosen region Zhůří for this work, which is one of the displaced villages at Šumava Mountains, which was part of the Dobrá Voda military training area. First, the work is devoted to the history of the village and then to changes in vegetation both directly and indirectly influenced by humans. The part of theme of this paper is primarily exploring areas of interest in terms of plant species, providing evidence of former settlements and making photographs and map outputs for each species found. The next theme is the evaluate of using the area from 1949 to the present, which over decades has fundamentally changed. Work also focuses on comparisons between the state of use from the 1949 today state habitat.

Interested in being notified about new results for this query?
Subscribe to the RSS feed.