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Vegetation of heat pipelines and participation of invasive species
SVĚTLÍKOVÁ, Petra
Both climate change and plant invasions are phenomenons affecting vegetation structure and its functioning. This study compares vegetation of heat pipelines with surrounding vegetation and investigated survival of thermophilic species in the zone on heat pipelines. Reactions of plants on global warming, including possible invasive behaviour of alien species, are briefly discussed.
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Invasive fish species in the Czech Republic
Lusk, Stanislav ; Lusková, Věra
In the Czech Republic, the following fish species are evaluated as invasive: Carassius auratus, a species showing a significantly negative influence on the occurrence of native species Carassius carassius and Tinca tinca in natural habitats. Certain manifestations and properties (such as the invasive way of dispersal, numerous populations, great ecological tolerance etc.) typical of invasive species can also be seen in Pseudorasbora parva, Ameiurus nebulosus, and Proterorhinus marmoratus. In some of its manifestations, even Cteropharyngodon idella can affect biodiversity in a negative way. One cannot exclude the future invasion or introduction of any alien species evaluated as invasive, particularly those of the genus Neogobius that occur in the Slovakian part of the Danube, and Perccottus glenii that has already invaded the Tisza River drainage area and the lower part of the Danube.
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The natural seasonal changes in the food choice and digestive tract of wild ruminants
Kamler, Jiří ; Homolka, Miloslav
Herbivore populations all over Europe have been strongly influenced by human activities. A combination of harvest, changes in forest structure, supplementary feeding, predator extirpation and others factors have led in most cases to increases of their populations and a severe impact on the composition and structure of the forest vegetation. The food choice of free living ungulate species is strongly influenced by season and animal species and changes in diet composition and quality cause the changes in the digestive tract. Effective management of ungulate populations and forest ecosystems should be based not only on detailed information about the impact of deer browsing and the number of deer to harvest but also on the density of deer species, the food supply, the structure of diets consumed by individual species, attraction and quality of the individual components of food supply the total quality of food taken and seasonal changes in digestive tract.
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The wood plants in the mown meadow: the analysis of morphology, age, growth and surviving of woody plants on species-rich meadows in the White Carpathian. Bc. Thesis, in Czech.
MAZŮREK, Petr
This study deals with the presence of woody species in species-rich, savanna-like meadows (with scattered Quercus spp. trees) in National Nature Reserve of Čertoryje, Bílé Karpaty Mts., SE Czech Republic. The first part is a community-oriented study of variation of woody species composition on meadows with different land-use management (regularly mown, recultivated,abandoned etc.). Indirect ordination analysis (DCA) was used to relate woody species composition to land-use history (seven meadow types) and species composition of the surrounding vegetation. Further, attempts were made to explain the occurrence and survival of woody species by their life-history traits (root:shoot ratio, regeneration ability after mowing etc). The second part of the thesis tries to identify the most prominent climatic factors affecting the growth of two common oak species in Čertoryje (1) by establishing the mean relationships between tree ring residual chronology and climate through bootstrap moving correlation and response-function analysis, and (2) by distinguishing ``pointer years{\crqq}, which correspond to abrupt changes in growth pattern and reveal the tree-growth response to extreme climatic events, such as summer drought. Since the oaks are ring porous species with abrupt transition between earlywood and latewood, both parameters were measured and used to obtain subseasonal climatic information.
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Sukcese hmyzenek (Protura) a vidličnatek (Diplura) na haldách chemické továrny
Rusek, Josef
Primary succession of Protura and Diplura was studied on deposits of a former chemical factory at Petrovice u Karviné, NE Moravia, Czech Republic, in 1978-1979, 1993 and in 2002-2004. Chemically loaded deposits were 15, 25 and 60 years old in 1979 and a primary succession without plant re-cultivation took place there. The succession was delayed on small humps and slopes where the deposited substrate was covered by terrestrial algae, lichens and mosses. Protura did not enter the primary succession before a moss cover occurred on the 15 years old heap and they were represented only by .i.Acerentulus traegardhi./i.. Three species of Protura were established in the 20 years old grass-covered stage as well as on the 49 years old heap. They occurred in low densities up to the 74 years old stage (and older), in which a proturan community of 4-6 species was established.
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Determination of content substances for selected species and varieties of roses.
Slavíková, Eva ; Sus, Josef (advisor) ; Súkeníková, Tereza (referee)
This bachelor's work is focused on comparing the most significant content substance, vitamin C, in fruits of chosen rose kinds species and varieties. Herbal products are often seen by people as products of "second choice", when failure of allopathic treatment occurs, which is focused especially on suppressing symptoms of illness, but it ignores health of the human body as whole. That's why are herbal products often alternative for therapy of chronic diseases. The base of this work is extensive literary research and results of laboratory measurings. Literary part of this work includes description of botanical classification of rose plants. There is stated basic characteristic of individual rose species and their morphological features. In following chapters is composed overview of effective substances in rose fruits and their effect on human health. In practical part of this work are included results of laboratory tests for determining ascorbic acid content for chosen samples of rose species and it also includes results of weighing and measuring of fruit samples of chosen rose species. There are also stated chosen rose species and shortly their origin and description, in the beginning of practical part. For practical part were chosen samples of species. Results of practical part are compiled into statistic tables and graphs and it confirms high content of ascorbic acid in rose fruits. This content is in range of cca 300 - 900 mg.100 g-1. Due to growing interest in alternative treatment options and "clean" natural product, it can be assumed, that many plants of Rosaceae family will keep its place in treatment practice. Those plants will be used not only for treatment of acute and chronic diseases, but also for cosmetic products production, thanks to its large effects and process options.
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Documentation of the nature reserve Miletinska bazantnice (Czech Republic)
Stejskalová, Klára ; Skalický, Milan (advisor) ; Martinková, Jaroslava (referee)
The aim of this study is to document the floristic species diversity through research in the natural reserve Miletinska bazantnice. Documentation was carried out on the territory concerned during the growing season of 2015. There was a determination of vascular species. The research was mainly focused on endangered and protected species.
The whole area is part of sites of European importance under the Habitats Directive Natura 2000 Miletinska bazantnice was declared a nature reserve in 1954 with an area of 75, 43 hectares and is part of a small-scale specially protected area. Typical features of the area are remnants of natural Podzvicinsko geobiocenosis and therefore the reason for its protection.
Further it describes the history, characteristics of the territory and the natural conditions that are typical for the locality. These include soil science, climate, hydrological, geomorphological, geological and phytogeographical. On the territory of the nature reserve are recorded two memorial trees. It´s oaks (Quercus robur) called Zizkovy duby.
At present territories were found in protected and endangered species and classified under the Red and black list of vascular plants of the Czech Republic (Grulich, 2012) and Decree of the Ministry of Environment of the Czech Republic no. 395/1992 Coll. Into the category of rare taxa that require additional attention include species such as Carex otrubae, Cerastium lucorum, Daphne mezereum, Galium boreale, Listera ovata and Primula veris. The only species Platanthera bifolia is ranked in the category of endangered under both the Red and black list of vascular plants in the Czech Republic and under Decree.
In the field survey, attention was also paid to invasive species, sorted by Catalogue of alien plants of the Czech Republic (Pyšek et al., 2012) and categorized archeophytes (Arctium tomentosum, Cirsium arvense, Convolvulus arvensis, Chelidonium majus)
and neophytes (Arrhenatherum elatius, Impatiens parviflora) and described their risks (Mlíkovský and Stýblo, 2006)
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Arctic tundra dendrochronology
Lehejček, Jiří ; Svoboda, Miroslav (advisor) ; Monika, Monika (referee)
Historically unprecedented environmental change in the Arctic ecosystems is often given into the context of its past and possible future development. In the region where instrumental meteorological observations are scarce archives need to be investigated in order to address this issues. The comprehensive synthesis one of the archives: long-live circumpolar evergreen Juniperus communis L. shrub is presented here. 20 individuals from southwest Greenland were investigated at the cell anatomy level to understand the ecology of the species and unhide its potential for environmental and climate reconstructions. The findings are as follows:
i) Stop of exponential cross-sectional conduit-lumen widening with increasing age is in contrast with conduit-lumen nature of trees. This indicates that shrubs do not need to saturate their water and nutrient demands via traits of classical hydraulic conductivity law but rather developed different mechanisms. Extreme weather conditions result in prostrate growth form. However, different weather factors probably influence shrub growth differently: While snow and wind act mechanically (a), temperature influences the form of growth physiologically (b). a) So long as the young shrub stem has high resilience to bend back to an upright position after snow melt and so long as it can withstand the wind during the vegetation season it most likely grows upright and the conduit-lumens widen. b) Temperature, resp. freeze-thaw events are responsible for the shrubs preference of safety (finite size of conduit-lumens) over hydraulic efficiency, thus not allowing for more primary growth. All of these (and other) factors are apparently working together and the transition of vertical to more horizontal growth is gradual. As a consequence, the conduit-lumen sizes may not have to be further increased (due to ecophysiological restrictions possibly also must not) because water is no longer transported against gravity.
ii) Observed age/growth trend has to be taken into consideration for further employment of the wood anatomical parameter in paleoenvironmental studies. That is, shrub cell parameters can only be used for this purposes if correctly detrended. This allows for more accurate as well as longer reconstructions because youth trend was often neglected in reconstructions based on shrub annual-rings.
iii) The south-western Greenland Ice-Sheet (GrIS) melt rates reconstruction is presented for the whole 20th century. This part of GrIS is considered as the most active. According to the presented reconstruction current GrIS melt rates are not uncommon for the last century being comparable to first decades of 20th century. This finding is particularly important contribution to the debate on Atlantic meridional overturning circulation (AMOC). Too high fresh water inputs into the Northern Atlantic from GrIS melting may slow down or even stop the AMOC which would result in more continental climate in Europe. Presented results indicate that this threshold lies higher than observed current melt rates of GrIS.
Fascinating Juniperus comunnis species has shown to be able to address many ecological as well as environmental open questions and due to its longevity and abundant distribution has a great potential to become an important player in the Arctic research.
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