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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...
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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...
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Complex ichtyological investigation of the Lipno Reservoir in 2017
Soukalová, Kateřina ; Kubečka, Jan ; Bartoň, Daniel ; Děd, Vilém ; de Moraes, Karlos Ribeiro ; Jůza, Tomáš ; Souza, Allan T.
The aim of the study was to monitor the overall status of the fish stock of the Lipno reservoir in the key year 2017, when the fishing rules were changed. The catches of multimesh gillnets, fry trawling, seining and electrofishing, and the assessment of European catfish were evaluated. The species composition and relative abundance of fish in all significant reservoir volumes were found, and the year class strength of all species 2017 was quantified. The report also contains recommendations for further fishery management of the reservoir.
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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
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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...
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Complex ichtyological investigation of the Lipno Reservoir in 2016
Soukalová, Kateřina ; Jůza, Tomáš ; Kubečka, Jan ; Bartoň, Daniel
The aim of the study was to monitor the overall status of the fish stock of the Lipno reservoir in the key year 2016, when the fishing rules were changed. The catches of multimesh gillnets, fry trawling, seining and electrofishing, and the assessment of European catfish were evaluated. The species composition and relative abundance of fish in all significant reservoir volumes were found, and the year class strength of all species 2016 was quantified. The report also contains recommendations for further fishery management of the reservoir.
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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
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Factors affecting population dynamics of endangered plant species Dianthus arenarius subsp. bohemicus
Sejrková, Petra ; Dostálek, Tomáš (advisor) ; Ekrtová, Ester (referee)
This diploma's thesis deals with critically endangered species Dianthus arenarius subsp. bohemicus from family Caryophyllaceae. Its distribution range is now limited on its last natural locality in National natural monument Kleneč. As a result of the change in land use (especially the abandonment of grazing), there was a significant reduction in its population size at the end of the 20th century and it was close to extinction. That is why action plan for species conservation was approved, which included number of management interventions at the locality. The most important was the removal of the upper humus horizon, which aims to create free gaps in the sand that allow the emergence and growth of new plants of D. arenarius subsp. bohemicus. The study species is also attacked by herbivores and it was predicted that increasing population might be endangered with increased herbivore population. The aim of this thesis is therefore to describe the population dynamics of the species, to evaluate the effect of the management and to determine how the herbivory affects the population dynamics of the species. The population growth rate decreases over time with vegetation succession. Even eight years after removal the population is still growing. The population growth rate is most affected by change in...
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Mechanisms driving di- and tetraploid coexistence in mixed-ploidy populations of Tripleurospermum inodorum
Nedomová, Anežka ; Čertner, Martin (advisor) ; Dostálek, Tomáš (referee)
Genome duplication plays a significant role in plant evolution. Formation of new polyploids is generally considered to be rare. Nevertheless, under natural conditions mixed-ploidy populations occur in relatively large numbers. Only the observations in the cytotype contact zone can identify all the factors affecting the stability or instability of the population. Number of research focusing on study of cytotype coexistence in natural mixed-ploidy populations is still low. As a model system for the study of mechanisms governing cytotype coexistence was chosen the Tripleurospermum inodorum. Research focused on natural mixed-ploidy populations and also on planted mixed-ploidy populations. Permanent plots were located in south, west, northwest and north Bohemia. Field observations were supplemented by cultivation experiments carried out in the greenhouse. Several phenomena were discovered at the level of whole populations. Cytotype distribution in the plot was random. The spatial structure of natural populations was quickly changing even within a single season. Even between single plot evaluations the cytotype ratios varied. Three percent of all plants were triploid hybrids. Most often detected cytotype in soil seed bank was diploid cytotype. The study of population dynamics shows, that tetraploids are...
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Factors influencing population dynamics of rock outcrop plants
Nováková, Terezie ; Münzbergová, Zuzana (advisor) ; Dostálek, Tomáš (referee)
Because the rock outcrops are inhospitable habitats with unfavorable conditions, rock outcrop plants have evolved special adaptations. Species occurring on such habitats are very often threatened or endemic. It is thus necessary to focus on this group also in terms of its life cycle and population genetics, because the size and evolution of populations and their genetic diversity are important factors for their conservation. For these purposes, we study their population demography. Based on transition matrices we can reveal the future performance of populations. Genetic analysis can help us to reveal the direction and intensity of the gene flow and genetic diversity of populations. This thesis is a literature review summarizing the current knowledge of rock outcrop plant species, their population biology, genetics and other factors influencing it. The second part outlines the research conducted on Aurinia saxatilis subsp. saxatilis and shows the first results of the future diploma thesis.
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