National Repository of Grey Literature 54 records found  beginprevious12 - 21nextend  jump to record: Search took 0.14 seconds. 
Implication of snow leopard distribution, population dynamics and landscape genetics, and prey preference for its conservation in Nepal
Shrestha, Bikram ; Kindlmann, Pavel (advisor) ; Sedláček, František (referee) ; Červený, Jaroslav (referee)
This thesis deals with an endangered large mammal species - snow leopard, its distribution, population dynamics, landscape genetics and connectivity, trophic ecology and human-snow leopard conflicts in the Nepalese Himalaya (Sagarmatha National Park (SNP), Lower Mustang (LM) and Upper Manang (UM) in the Annapurna Conservation Area, during Wet and Dry seasons in 2014-2016. In the case of snow leopard study, we used data obtained from camera traps, scat's genetic analysis and monitoring of fresh pugmarks and scrapes while direct count method was used to study for its main prey, blue sheep and Himalayan tahr. In study 1, we assessed the determinants of habitat suitability of snow leopards using MaxEnt model and mapped the distribution of suitable habitat for snow leopards in Nepal. Altitude and Annual mean temperature are important common factors contributing to snow leopard habitat suitability within the area studied, which is indicated by both the percentage contribution of environmental variables and Jackknife test from MaxEnt model. Some other uncommon factors also seem to play a role, as they were important in at least one of the analyses. These were: distance from road, and precipitation of driest month but their importance has to be considered with caution. In study 2, we present our...
Population dynamics of Minuartia smejkalii
Hrušková, Karolína ; Münzbergová, Zuzana (advisor) ; Dostál, Petr (referee)
Serpentine areas in the Czech Republic form minor but important islands in the landscape with specific chemical properties such as high content of magnesium and other heavy metals. Due to this, serpentine is toxic for most plants. Increased demands on the survival and occurrence of plants lead to the emergence of serpentine specialists obligatorily specialized in these extreme habitats. Currently, serpentine areas are threatened by gradual overgrowth of sites, insufficient or poor site management and fragmentation or shrinkage of sites due to anthropogenic activities. Along with the disappearing localities, the serpentine specialists, are becoming highly endangered. Minuartia smejkalii is highly endangered serpentine specialist with an endemic occurrence in the Czech Republic with great need of its conservation. The aim of the work was to collect data on population dynamics of the species and identify habitat and climatic factors affecting population growth. We studied dynamics in all existing 7 populations during the period from 2006 to 2020 were collected. We linked these data to information on population dynamics, habitat and climatic factors and analysed them using Integral projection models (IPM). The study presents the importance of individual habitat and climatic conditions on the dynamics...
Boryt barvířský (Isatis tinctoria) jako potenciálně invazní druh v CHKO Pálava. Vyhodnocení efektivity různých likvidačních opatření
Klepárníková, Michaela
This study is focused on the monitoring of the population dynamics of the dyer's woad (Isatis tinctoria L.) in the National Nature Reserve Děvín-Kotel-Soutěska. In the course of thesis, monitoring areas were established to assess the most suitable liquidation interven-tion in the case of a progressive invasion of the species in the location. The number of plants and their distribution on the area were continuously monitored and compared to the previous period. Results of study are a detailed plots of areas and a tables with num-bers of plants in 2015 and 2016. During the first two years of monitoring, there has not yet been a statistically significant decrease in either of the monitored localities. The reason for this can be the long-term supply of viable seeds in the soil, and according to profes-sional literature it can be assumed that the differences in the types of interventions that occur will take effect after several years. Due to the application of herbicide preparations, we can recommend Dicopur M 750 as the most effective for dyer's woad. Results of this study will serve as a background material for the Administration of Protected Landscape Area Pálava and for Nature Conservation Agency of Brno.
Loranthus europaeus Jacq. verzus druhy r. Quercus L. resp. Carpinus L. =: Loranthus europaeus Jacq. vs. Quercus L. resp. Carpinus L. genera. /
Kubíček, Jan
A better understanding of host – hemiparasite association can lead to deepening and improving strategies, which would result in a long-term sustainability of their mutual balance or prosperity of urban and forest vegetation growth. The aim of the thesis is to describe and explore periodicity and dynamics of hemiparasite (Loranthus europaeus Jacq.) on various host woody species (Quercus petraea (Matt) Liebl., Carpinus betulus L., Prunus spinosa L.), options of the host support and means of a careful removal of parasite. However, to determine the progress of the infestation in time was the primary aim of the thesis. The research has been carried out in Brno – Kohoutovice and National Park Podyjí. The emergence of both hemiparasite´s and host´s phenophases were mutually compared in the critical conditions. The variation of the growth modules of mistletoe was compared in relation to the host species. The growth and fruit yield of the host and hemiparasite were analysed after the application of fertilizer based on the variations of the mineral content of leaves and soil. Between the years 2011-2015, 1599 stems were monitored for the degree of infestation by mistletoe. The results indicate that the vitality of the hemiparasite depends on the type of host. Fertilizer application improved the growth of the host. Arboricide application on the leaves of the hemiparasite was proven to be efficient. The abundance of hemiparasite increases with the increasing diameter at breast height (DBH), time and mutual interaction. The amount of hemiparasite slightly increases with the lower DBH. However, with the increasing DBH the mentioned phenomenon decreases. The trees with high DBH even show the decrease in the mistletoe infestation in time. Nevertheless, the decrease was accompanied by negative effect – gradual reduction of the crown and loss of the host tree branches. Hemiparasite is able to eradicate the whole stand. Hence, the necessity of paying attention to this issue since the young age of the individual trees. It is necessary to protect trees against stress aspects which can accelerate the negative effect of hemiparasite on the host.
Ekologická studie dračince rumělkového (Dracaena cinnabari) na lokalitách Firmihin a Scand, ostrov Sokotra
Hubálková, Irena
The results of Dracaena sub-populations research are submitted in this dissertation. Dragons Blood Tree is an endemic plant species growing on the Socotra Island. The thesis contains four scientific papers published or submitted for review in journals with impact factor and in peer-reviewed journal. The first article predicts sub-population dynamics on Firmihin where the ha sample plot inventory was carried out. Tree growth and mortality simulation has been created using a time horizon of 100 years. The second article is focused on growth dynamics of seedlings growing ex situ under controlled conditions. One hundred plants from Firmihin and Skand have been measured once a week for two years. The differences in growth dynamics and mortality for both groups of young plants in ex situ were evaluated. The third article also relates to Dragons Blood Tree regeneration and deals with a possibility of in-situ regeneration in the fenced area on Shibehon Plateau compared to Oam al-Cora school grounds. The team from Mendel University in Brno planted hundreds of seedlings in 2006, ever since the monitoring of growth dynamics and mortality continues. The fourth article deals with anatomy of secondary thickening plant organs. Xylem, phloem, parenchyma and vessels area of root, stem and branch was determined using 70 permanent microscope slides and processed by image analysis. The results were evaluated, compared and graphically interpreted.
Changes in the distribution of invasive neophytes in the riparan vegetation of the Berounka river
Randová, Nela ; Matějček, Tomáš (advisor) ; Lipský, Zdeněk (referee)
Riparian vegetation along the water courses is one of the places that are highly vulnerable to the spread of invasive alien plants. Water corridors allow their easy and rapid spread to new area. The diploma thesis occupies with changes in the distribution of the invasive neophytes in the riparian vegetation of the Berounka river during the years 2015-2018. The objective of this study was to find out how changes in the course of each year will be reflected and whether a certain trend of population development can be traced. In connection with this, the thesis occupies with the possible influence of extremely dry years 2015 and 2018 on the occurrence of invasive neophytes. Field research took place on the banks of the Berounka river from the village of Čilá near Skryje to the confluence of the Berounka and Vltava river in Prague-Lahovice during the summer months in 2015, 2016, 2017 and 2018. The riparian vegetation was divided into 500 ± 150 m long segments. There were 90 segments where the occurrence and abundance of 17 invasive neophytes were mapped. In total, occurrence of 14 taxons was registered. The most frequent taxons were Robinia pseudacacia, Impatiens glandulifera and Solidago sp. in the Berounka riverbank vegetation. The highest number of specimen was recorded for invasive neophyte...
Modeling population dynamics of plants and possibilities of connecting population data with data on environmental conditions
Hrušková, Karolína ; Münzbergová, Zuzana (advisor) ; Dostálek, Tomáš (referee)
Dynamics of plant populations is influenced by climate and habitat conditions. To understand performance of plant populations and to find out their possible future development, it is important to identify these drivers and to describe their impact. Based on data of performance of individuals in a population, models are used to predict the population development. Nowadays there are efforts to include environmental drivers and climate changes into population models, which make estimations of population development more exact and realistic. It is important to define a suitable management on locations with endangered species and to target the management on critical transitions between life stages which impact the population development the most. These models indicate the most vulnerable transition stages of a life cycle. This bachelor thesis is a literature review which provides a brief summary of the current population models and it is trying to give their brief characteristics. It also provides examples of drivers which influence the dynamics of plant populations and describes possibilities of connecting environmental data and species population dynamics. The final part of the thesis briefly explains the research which is being done on the species Minuartia smejkalii. The influence of climate and...
Winter irruptions of birds in Europe
Souček, Michal ; Lučan, Radek (advisor) ; Hořák, David (referee)
Besides regular migrations, a phenomenon called "eruption", "invasion" or "irruption" exists in bird migratory behaviour. Although this phenomenon has been known since 19th century, its basic mechanisms are still not clear or are subjects of discussion. This bachelor thesis summarises in a form of review up-to-date knowledge and theories about winter irruption with information about all winter irruption occurrences in Czech Republic. Key words: Aves, irruption, winter invasion, migration
Population biology of rock outcrop plant Aurinia saxatilis ssp saxatilis
Šimáková, Terezie ; Münzbergová, Zuzana (advisor) ; Dostál, Petr (referee)
The rock outcrop plants are neglected group of plants, even though they include endangered or endemic species. Despite this fact, there is only a few of studies focusing at this topic. The aim of this thesis is to focus on this group of plants in terms of its population dynamics. Aurinia saxatilis ssp. saxatilis was chosen as a model species. It is a species of the Czech thermophyticum. Three populations were chosen and studied over three years. The population dynamics was compared between the populations by integral projection modelling (IPM) and matrix population modelling (MPM). The results of these two analytical approaches were compared to one another, too. The population growth rate (λ) predicts that one of the populations is stable, whereas the other two populations are declining. The highest elasticity is mostly for the seeds survival in the seed bank. The population growth rate does not differ distinctly between the two statistical approaches, IPM and MPM. In all cases the IPM λ is lower than the MPM λ. Within the IPM analysis, the influence of the substrate type was also studied. The analyses, however, did not indicate any major differences between the substrates. For maintaining the populations, it is necessary to protect the new seeds and seedling recruitment and to create the new space...
Spatial correlations in population dynamics of spruce bark beetle (Ips typographus): Example of Mantel test usage
Šimera, Ondřej ; Kindlmann, Pavel (advisor) ; Ferenc, Michal (referee)
Spruce bark beetle (Ips typographus L.) is the most common and abundant beetle from the Scolytidae family in European forests. It is the most important biotic factor causing disturbances and affecting forest ecosystems. Thus, it recently became a subject of discussions, how to manage the forests properly in order to find an adequate equilibrium among economical, turistic and natural values of the forest. Many studies have shown a positive effect of bark beetle outbreaks on biodiversity and natural forest regeneration. It is hard to tell if these outbreaks are regular or not because there are many factors which can elicit them. However, just these factors can help us predict the probability of unforseen population outbreak. One of these methods can be monitoring of surrounding areas because these areas tend to be synchronised. For this purpose, multiple mathematical models can be performed, such as the Mantel test, which determines the correlation between two matrices. Keywords: Spruce bark beetle, Ips typographus, population dynamics, spatial correlations, Mantel test

National Repository of Grey Literature : 54 records found   beginprevious12 - 21nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.