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The aims of my PhD thesis are to find out occurence of resistance population of pollen beetle, degree of resistance in population and to suggest possible change of the antiresistant strategy. At the same time it was investigated identification of pollen beetle species (Brassicogethes spp., Meligethes spp. and others) and their dominance in oilseed rape. Populations were collected from commonly used fields of oilseed rape, mustard and poppy in the region of central and southern Moravia and Bohemian-Moravian Highlands in 2009, 2010, 2011, 2012. The individuals were exposed active ingredients lambda-cyhalothrin, ethofenprox, cypermethrin, tau-fluvalinate, chlorpyrifos (ethyl) and the preparation Biscaya 240 OD according to methodology of Insecticide Resistancee Action Committee (IRAC) number 011, 021, 025. Decreased effectivenes active ingredients from group pyrethroids a neonicotinoids among individual year were found. There are resistance populations. The Cross Resistance were discovered between active ingredient lambda-cyhalothrin and ethofenprox. Active ingredient chlorpyrifos (ethyl) were the most effective of all active ingredients which were tested. Pollen beetle (Brassicogethes aeneus) was the most frequent species in all compared samples (2009 -- 2011). From the accompanying species B. subaeneus and B. viridescens were markedly more frequent in this study. To find out differences among the individual pollen beetle species during the laboratory tests of their susceptibility to insecticides is very important. It shouldn't used or combined active ingredient lambda-cyhalothrin and ethofenprox and another active ingredient should changed intensively.

Species distribution models (SDM) are widely used tool in biogeography, macroecology and nature conservation. With gradual development, it has become an important means used by, for example, in determining the potentially threatened locations by invasive species, or studying the impact of climate change on biodiversity. With the progressive development it becomes obvious that one of the major factors limiting the species distribution modelling are input data. The presence data are most readily available, but they suffer from an uneven collection, for example, with a predominance of records in easily accessible locations. The aim of this work is to show, that popular climate filtering of presence data input, in order to eliminate uneven sampling, affects the final model in a negative way. For this purpose, there were virtual sorts of different species and different prevalence of recorded occurrences on the territory of the Iberian Peninsula generated. Subsequently, species distribution models with and without climate filters were created by using Maxent. They were evaluated by AUC. The difference between virtual reality, which is presented to the suitability of the virtual species, and the resulting model was tested by paired T test. Comparison of the AUC confirmed that the species distribution models based on climate filtering have better discriminative ability. However, it only points to the skilful work with the selected sample bias that already does not reflect reality. In contrast, comparison of the differences between virtual reality and the models with and without climate filtering using a paired T test shows greater congruence between unfiltered models and virtual reality. Thus it was proved that the climate filtering does not lead to higher validity species distribution models.

The work is focused for the use of the monitoring of the content of RP realized ÚKZÚZ in forest soils Novohradské Mountains and the Beskydy mountain, statistical assessment of the level of RP content in soils and their spatial distribution and evaluation of the influence of factors, statistical comparison between the different areas of content, different types of vegetation, soil horizons (analysis of variance, t-test). They assessed the relationship between the content of individual RP and RP between content and soil properties (correlation and regression analysis). The work also contains maps of the spatial distribution of content RP in forest soils of the area.

In this study we deal with comparison of insect monitoring methods on flowering strip, wheat and oilseed rape. The experiment is located at two study sites: Crop Research Institute at Ruzyně and Experiment unit of Czech University of Life Sciences in Uhříněves. The experiment was carried out in 2015. To make monitoring we utilized sweeping net, Möricke yellow traps, transect counting and as a supplementary method we utilized light trap. Monitoring was done in 25 of June, 16 of July and 12 of August 2015. These dates were chosen because of flowering of the strip which was the most important issue in this study. As a result of this the insect diversity in other almost harvested variants was quite low. The most important insect species quantities were collected from Möricke traps in all three variants. But this fact could be naturally based on the attractivity of the yellow color, so we can´t reliably say, if in out of bloom rape or wheat could be present this high amount of insect or if it is only being attracted by color of the trap from the neighborhood. The second method with the highest insect occurrence was sweeping net. Again the highest species diversity was described from the flowering strip. The lowest amount of insects was noted in transect counting. This method has (contrastingly to the others) disadvantage in the high possibility of fail to detect small insect, which are normally noticed by the other methods. Light trap monitored about the highest species number, where the majority of species belong to order Lepidoptera. That sway this method was employed only to enrich the species diversity.

Angl. resumé

Dry grassland are among the most endangered plant communities mainly due to the overgrowth of a number of localities. That is why from the beginning of the 21st century pasture with mixed herds of sheep and goats is restored on the most valuable dry grassland sites in the Bohemian Karst as the way of maintaining these habitats. Concurrently, research sites each 1x1 m in size were set up at four pastured localities, and were paired with control sites equipped with a fence for the research of grazing effect on vegetation. The main aim of this work was to evaluate the effect of grazing on the diversity of bryophytes at the forty pairs of the above-mentioned areas in three types of calcareous dry grasslands. In addition to the inventory of bryophytes, data on the most important abiotic and biotic factors of the environment were recorded on individual sites. The total number of bryophyte species found at the research sites is 46. 37 species were found at the grazing areas and the same number was at the fenced areas. Minimal differences in the number of species of grazed and unspoilt areas were also found in the comparison of individual localities. The grazing effect was shown up more significantly on species richness in the comparison of individual types of communities, especially in broad-leaved dry grassland (T3.4). There was a 40% increase in the number of species on grazing areas. The environmental factors have a positive effect on the species abundance mainly due to the higher slope of the terrain and the correlation with the larger occurrence of the stones, the smaller coverage of the herb layer and the litter. These conditions prevailed in areas with rock outcrop vegetation with Festuca pallens (T3.1), where the largest species richness of bryophytes in area was found. In the obtained data, the influence of grazing on the species composition of bryophytes on grazed and unspoilt areas was also assessed with the statistical methods and the Sörensen test of beta-diversity. The results show that grazing significantly influences the species composition towards open grassland and supports the growth of the bryophytes T3.1 plant community at the expense of the T3.4 plant community

CARBON AND NITROGEN POOLS AND FLUXES OF TWO FOREST ECOSYSTEMS IN THE ORE MOUNTAINS With increasing atmospheric CO2 concentrations, forest ecosystems are considered for their sequestration ability. However, there are differences between coniferous and deciduous tree species in their impact on the carbon (C) and nitrogen (N) fluxes within forest ecosystems, which influence soil carbon and nitrogen pools. In natural beech and monoculture spruce stands on research sites of Czech Geological Survey in the Ore Mountains, C and N fluxes and pools were investigated. There were investigated ecosystem inputs (C, N, in throughfall, litterfall) as well as outputs (soil respiration, concentrations of C, N in seepage water discharge). Further, C and N pools of living biomass and soils were determined. Throughfall DOC was significantly higher in the spruce stand, on the other hand litterfall C flux showed the opposite relationship. At output, DOC, DON and NH4 + discharge fluxes from O horizon were significantly higher in the spruce stand whereas in the beech stand higher NO3 - flux from mineral soil was recorded. Soil respiration was quite similar in the both stands, however different parts of original sources of respiration among tree species were different. Beech stand has larger pools of carbon and nitrogen in...

Lichens are a classic example of mutualistic symbiotic associations, yet the views on lichen symbiosis have changed considerably during the last fifty years. Nowadays, lichens are generally understood to be microecosystems consisting of several symbiotic partners which contribute in different ways to the prosperity of the whole system and which differ by the strength of their bond to other symbiotic partners. The level of knowledge of the individual partners (mycobionts vs. photobionts vs. bacteria) varies greatly in terms of their specificity, diversity and in the forces that shape this diversity. The main aim of this work was to reveal the diversity of organisms participating in lichen symbiosis and to better understand the biological forces which shape this diversity. We worked with a relatively common lichen group, zeorin-containing red-fruited Cladonia species, and specifically, we focused on the mycobionts, photobionts and bacteria that participate in this association. During the course of the study, it became apparent that species delimitation, which is a fundamental requirement for accurate diversity estimates, is another topic that requires further research. Our analyses revealed that species circumscription of most of recently recognized Cladonia mycobionts cannot by supported by...