National Repository of Grey Literature 54 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Edge of habitability: bird community on dump sites after uraninite mining
KOREJS, Kryštof
Biota on post-mining areas is a well-examined topic in restoration ecology. However, most scientific attention focuses on large-scale opencast mining sites or spoil heaps. This study attempts to offer an insight into ecological conditions on a unique ecosystem represented by dump sites after uranium mining, using birds as a study group. We examined differences in bird abundance, species richness, community structure and habitat preferences between nine moderately sized dump sites and eight control areas. Our study can function as a pilot survey of birds of uranium mining sites, offering a broad overview of population-level effects of hostile conditions. Our findings can guide restoration practices with respect to this specific type of ecosystem.
Species diversity of vascular plants in alpine vegetation of the Western Carpathian mountains on different spatial scales and its connection to soil pH
Anderlová, Nikoleta ; Sklenář, Petr (advisor) ; Macek, Martin (referee)
Alpine regions are hotspots of species diversity and are therefore at focal center of scientific interest. The research aiming to understand the influences and patterns that shape this unique environment, is complicated by mulitple metodological issues stemming from unclear definitions of used terms as well as the existence of various methodological approaches and their constrains/limitations. The breadth of the topic of species diversity, which can be viewed from multitude of perspectives, is also adding to complications. This work summarizes the most important information in available literature and addresses important correlations and trends in environmental variables and species diversity of alpine meadows in the areas of Malá Fatra, Nízke Tatry, Roháče, and Belianske Tatry. At the center of attention is the widely accepted theory of higher species richness in areas with basic, calcareous substrates compared to areas with acidic, silicate substrates in Europe. To confirm this theory at different spatial scales in alpine environment, hierarchical sampling was chosen. A total of 96 samples containing data on the presence/absence of plants and relevant environmental factors, including pH measurements, were obtained. The structure of these data was visualized using ordination techniques such as PCA...
Drivers of ectomycorrhizal fungal species richness on large spatial scales
Petr, Andrej ; Kohout, Petr (advisor) ; Šímová, Irena (referee)
Ectomycorrhizal (EcM) fungi form mutualistic relationships with some woody gymnosperms and angiosperms that play an important role in the functioning of most terrestrial ecosystems. Using enzymes capable of sequestering nitrogen and phosphorus from complex organic compounds, EcM fungi make these elements available to their host plants, which in turn provide them with the carbon compounds on which EcM fungi are vitally dependent. However, different species of EcM fungi differ from each other in their ability to sequester nitrogen and phosphorus from organic compounds, as well as in their carbon requirements from plants. The importance of the EcM symbiosis for the ecosystem therefore depends on the species richness of the EcM fungi, which is influenced at large spatial scales by a number of interacting factors, in particular the density and diversity of host plants, climate and soil properties. As EcM fungi generally exhibit low host preference, the density of host vegetation and the associated higher nutrient availability for EcM fungi has a greater influence on their species richness on a global scale than the phylogenetic diversity of host plants. In addition to these environmental factors, however, the distribution of EcM fungi is strongly related to their biogeographic history. In the context of...
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...
Long term dynamic of vegetation succession on post-mining sites.
Skalníková, Andrea ; Mudrák, Ondřej (advisor) ; Janíková, Eva (referee)
Spontaneous succession of vegetation can be one of the restoration approaches of disturbed sites after coal mining. It is therefore important to know the course of successional changes and whether it can be replicated. The spontaneous succession of vegetation on disturbed sites is usually based on monitoring of multiple sites of a different stage of succession. By their comparison the course of the succession over time is inferred. This approach of the study is called chronosequence (space-for-time substitution). Another option is to repeat monitoring of permanent plots, but it requires a long period of time to observe successional changes. Rarely are these approaches combined. In this thesis, I analyse the main trends in the succession of plant communities and their plants functional traits on five localities of various age during the 15 years. I have examined whether the localities follow similar successional trends. Data (plant coverage) were collected by annual resampling of 50 (ten per locality) permanent plots of 5 m x 5 m since 2007. By performing a multivariate CCA analysis, we analysed the species composition of the plant community, and by performing an RDA analysis, we analysed the changes in weighted averages of plant functional traits. In both cases, the localities and their...
The possibilities for mire restoration from soil seed bank: The extinct mire near the fishpond Příbrazský rybník
ČÍŽKOVÁ, Eva
As a result of the increasing demands of human society, natural habitats are being used, disturbed and destroyed. Human activities also significantly affect peatland habitats, which leads to their loss, as a reasult of which these habitats are endangered in many European countries, including the Czech Republic. The loss of peatlands is evident both locally and globally, so in recent decades increasing efforts to restore these habitats. The soil seed bank, which was produced before their disturbance, can be used to restore the species composition of degraded habitats. However, in this way it is possible to restore only those plant species that produce a persistent seed bank in the soil. Furthermore, it is necessary to realize that the soil seed bank is very heterogeneous, both in the number of viable seeds and the number of species. In this diploma thesis, the soil seed bank from extinct peatland habitat, which is located by the Příbrazský pond in southern Bohemia, was examined in ex-situ conditions. The subject of the research was mainly the species composition of plants grown from the soil seed bank, which was taken at different places in the locality and at different depths of the soil horizon. From the examined soil seed bank of the extinct peatland habitat, 54 species of plants grew, thereof 13 of them are evaluated as endangered or near threatened in the Czech Republic, which means that the soil seed bank is able to increase the species richness of the locality. Examining the soil composition of the soil bank, which was taken at different depths of the soil horizon, it turned out that the numbers of individuals and species able to germinate from the soil seed bank gradually decrease since the extinction of the peatland habitat, so it is more advisable to use a not too old soil seed bank in the upper layer of the soil horizon. Furthermore, it was found that the species composition of the soil seed bank is dissimilar in different places of the site, which suggests that it is advisable to restore the extinct habitat at a place whose soil seed bank contains the target plant species.
Vliv managementu na složení rostlinných společenstev a na ohrožené zájmové druhy NPR Vyšenské kopce
VACEK, Michal
The study assessed the impact of grazing on the composition of plant communities and endangered plant species. We studied the effect of grazing using (grazed and ungrazed control) permanent plots established 20 years ago in a semi-natural calcareous grassland in the National Nature Reserve Vyšenké kopce, and established new permanent experimental treatment plots for mowing. We compared the species composition and the numbers of species between managements and compared the results based on monitoring in different seasons of the year.
Vliv tvaru potravních zdrojů na společenstva afrického koprofilního hmyzu
HELCLOVÁ, Michaela
This research focuses on communities of tropical dung-inhabiting insects and their relation to spatial parametres of their habitats, namely the dung pat shape and surface area. Study was carried out in South Africa. The aim of the study is to test differences in functional structure of coprophilous communities, its abundance and species richness across normal dung pats and dung pats with four times larger surface area. The results suggest that preference for habitat with different areas plays a crucial role for avoiding competition between dung-inhabiting insects.
Coexistence of plant species in fragmented landscape
JANEČKOVÁ, Petra
Semi-natural grasslands are hotspots of biodiversity in the present-day landscape. The thesis focuses on various effects and processes affecting plant species coexistence at two different scales. At the local scale, the effects of management and fertilization were assessed in relation to abiotic gradients and species functional traits. At the landscape scale, the patch spatial configuration, land use and plant functional traits may influence species distribution. The diversity pattern in fragmented landscape is also modified according to availability of suitable patches and landscape heterogeneity.
Pasture of horses as an essential tool in biodiversity conservation
Dudková, Andrea ; Malíček, Jiří (advisor) ; Sedláček, Ondřej (referee)
In recent decades, the approach of active management, preventing overgrowth and simplifying the species composition of non-forest biotopes, has dominated in nature conservation. Dominant plants, suppressing competitively weaker species, are therefore reduced for example by grazing of large herbivores. It turns out that horse grazing has considerable potential for enhancing biodiversity. The aim of this bachelor's thesis was to summarize the main aspects of horse grazing based on literature research and come to a prediction of its future use in nature conservation. Studies on the use of horse grazing in biodiversity conservation show that it works well to suppress competitively strong grasses and supports the presence of flowering dicots and associated insects. The disadvantage of grazing horses is that they do not consume woody plants and thus cannot suppress the growth of bushes. On larger areas (>20 ha), year-round wild horse grazing is used, while domestic horses are suitable for seasonal grazing on smaller sites. Due to the positive results of horse grazing in promoting biodiversity, the more successful suppression of competitively strong grasses compared to other herbivores and the lower level of human effort compared to mowing, it can be expected that cases of using horse grazing in nature...

National Repository of Grey Literature : 54 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.