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Changes of biodiversity and composition of insect communities during restoration of tropical environments
Halamová, Pavla ; Tropek, Robert (advisor) ; Čížek, Lukáš (referee)
in English Tropical rainforests are the richest habitats, but most endangered habitats on the world as well. Given the current global trend of deforestation, successful restoration of secondary forests is necessary for maintaining the rich fauna and flora of tropical rainforests. Insects are the most diverse group of animals in the tropics and they have crucial roles in an ecosystem functioning. Restoration interventions in degraded forests are nowadays more common and case studies are involving insect communities, however no review of them has been conducted. The aim of this thesis was to summarize the results of hitherto published studies dealing with the insect responses to the restoration of the tropical rainforests. With the emphasis on logged forests and lands converted for agriculture, the insect species richness, abundance, diversity, and the changes of composition were studied. If ecological conditions are suitable, insect species richness, abundance, diversity, and similarity of composition tend to increase towards primary forests for majority of insect groups. However, we observe some differences across groups of insects, based on the type and severity of disturbance, and on specific conditions on the site. Keywords: insect recovery, tropical rainforest, disturbance, species diversity,...
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Vegetation changes in Czech lowland forests over the past decades
Kopecký, Martin ; Hédl, Radim (advisor) ; Chytrý, Milan (referee) ; Diekmann, Martin (referee)
Vegetation changes in Czech lowland forests over the past decades Martin Kopecký ABSTRACT To explore decadal changes in plant species diversity and composition of typical lowland forests in the Czech Republic, I compared vegetation on plots sampled decades ago with vegetation on the same plots sampled recently. First I evaluated the robustness of the approach used in my thesis. In Chapter 1, we provided the first direct test of the effect of uncertainty in original plot location on results from vegetation resurvey. We found that temporal trends in vegetation diversity and composition were comparable between exactly relocated permanent and only approximately relocated semi-permanent plots. Therefore, we conclude that the resurvey of semi-permanent plots is robust to the uncertainty in original plot location. Then, we showed that vegetation in lowland oak forest shifted from species-rich communities of thermophilous forest toward species poorer communities of mesic forest (Chapter 2). The species typical for thermophilous oak forests and nationally endangered species suffered the most significant decline. We identified as the main driver behind these changes shift from traditional coppicing toward high forest management after WWII. Further, we explored the processes behind temporal shifts in species diversity...
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Forest vegetation in Eastern Elbe Basin in the mid-20th century and today
Pospíšková, Marie ; Hédl, Radim (advisor) ; Novák, Jan (referee)
This thesis describes the shift in vegetation of broadleaf forests in eastern part of the Elbe River Basin between 1958-1968 and 2011-2013. It emphasizes the understorey vegetation. From lowland woodlands in other temperate regions in Europe and North America changes towards eutrophic and mesophytic vegetation are documented, specifically driven by changes in forest management and by atmospheric depositions; in some localities the game impact can be also important. The data were obtained by sampling 190 typological semi-permanent plots, which were precisely located - in 43% the original soil pit was found. The vegetation on study sites shifted towards nutrient-demanding, shade- adapted species, it was partly ruderalized. These changes can be seen on the level of species and communities as well as on phytosociological level. Increase of soil pH and moisture was discovered using Ellenberg indicator values. The number of seedlings and cover of shrubs also increased significantly. Homogenization of sites was significant as well although total number of species and alpha- diversity remained unchanged. These changes are probably caused by changes in forest management and by atmospheric depositions of nitrogen. On subset of plots in game-preserves the vegetation also demonstrated eutrophication but no increase in...
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Biodiversity of chironomid fauna in mountain lakes and streams influenced by acidification and recovery from acidification.
Černocká, Veronika ; Stuchlík, Evžen (advisor) ; Frouz, Jan (referee)
This thesis examines the influence of acidification on the largest group of macroinvertebrates in mountain lakes and running waters - chironomids. The diversity of chironomids has been associated with temperature, the concentration of dissolved oxygen in the water, the amount of nutrients, and also with the ability to survive in conditions (e.g. extreme pH) that are not suitable for other taxa. Because of this the family Chironomidae has become a dominant group of macrozoobentos in many assemblages affected by acidification. The Bohemian Forest lakes and the Tatra Mountain lakes belong to the most frequently studied locations, which were affected by acidification. The peak of acidification was in the 1980s. It turned out that, during the acidification, the number of chironomids changed and also the species composition of their assemblages. The main reason was a change of trophic status, which chironomids reflected more than a change of pH. A decrease in the number of species occurred after the pH dropped below 5. Until then, only their relative abundance had been affected. Chironomids are also influenced by the toxic effect of Al. The most important factor affecting chironomids fauna is not the value of pH, but the change of food supply. Acid stream food webs are often viewed as being...
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Species traits determining species composition on abandoned fields
Jarošíková, Cecílie ; Münzbergová, Zuzana (advisor) ; Klimešová, Jitka (referee)
Though succession is a widely studied process, there are only a few reports dealing with changes in plant functional types in the course of succession. Even fewer studies are dealing with agricultural, wet meadows, which are under continuous impact of mowing. The aim of this work is to fill this gap. The studied area is situated in south part of CHKO Slavkovský Les (region of Karlovy Vary, West Bohemia). In previous works grasslands on arable field after 15, 35 and 55 years after abandoned and continual grasslands in last 100 years were detected from historical agriculture maps. The releves on all types of grassland were made and the species pool was investigated. I this work I investigate the functional types and live-history traits of these species and I also look for Ellenberger values and changes of abiotic environment. The result suggests that the late - successional species are long-lived and have slower live cycle (they mature later). Their seeds are less persistent and have worse dispersal ability. Their seedlings are more viable and the species invest more to aboveground biomass than to underground. Late-successional species also flower earlier and shorter time, what seems to be an adaptation to mowing. I found no relationship between successional age in which the species occur and seed mass,...
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Forest vegetation changes in the Bohemian Forest during the second half of 20th century
Prach, Jindřich ; Kopecký, Martin (advisor) ; Sádlo, Jiří (referee)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
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The structure of dispersed vegetation around the village Ostretin
Hloušková, Jana ; Janeček, Vladimír (advisor) ; Vítámvás, Jan (referee)
Scaterred vegetation is a significant element in a landscape which has many functions. The main functions are ecological, soil-protective, microclimatic, productive, medical, and hygienic. This thesis is focused on species composition in scaterred vegetation. The aims of this thesis were to find out the species composition and also the habitat characteristics during the past dendrologic research. Also, it was important to determine which factors affect the species composition. A study was held in September and October 2015 around a village Ostřetín in region of Pardubice. 19 tree species and 9 bush species altogether were found in 70 locations. To the largest group of bush species belong Sambucus nigra, Rosa sp., Crateagus sp. and Prunus spinosa. As for the trees species, the most numerous groups were Alnus glutinosa, Prunus domestica, Pinus sylvestris and Picea abies. All the collected data were statistically evaluated using generalized linear model. Neither water nor altitude influence were conclusive. On the other hand, factors as area, canopy, vertical stratification and presence of dead wood were significant meaning they affected the species composition. Comparison of similar studies shown that the species as Rosa sp. and Sambucus nigra are significantly dominant bush species in scaterred vegetation. On the contrary, frequency of tree species is different in many cases.
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Species requirements on the structure of European mountain Norway spruce forest
Suderová, Natálie ; Čada, Vojtěch (advisor) ; Janda, Pavel (referee)
The aim of this bachelor thesis is to summarize conteporary studies about the biological and ecological characteristics and demands of the plant, animal and fungi species inhabiting montane Norway spruce forests, especially those of the red-list species.
An extensive systematic review was conducted as a part of this study, with a systematic research of Web of Science database, finding science studies containing key words referencing to high montane spruce forest and biotope demands of organisms. Out of a total 475 studies found in a Web of Science database, 57 studies were chosen with objectiv criteria, and 44 were cited in the bachelor thesis.
Bachelor thesis chapters were dedicated to functional groups of organisms, as often found in studied literature, i.e. vascular plants, fungi, lichenes and epiphytes, arthropods and nematodes, birds, mammals and amphibians.
Several structural key elements were found to be significant for the abundance, biodiversity and species composition of organisms inhabiting high montane spruce forest. These key elements are forest structure, deadwood, admixture tree species and environment pollution.
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Assessment of potentially toxic element contents in forest soils of selected regions with differing level of pollution
Džermanská, Lenka ; Borůvka, Luboš (advisor) ; Přemysl, Přemysl (referee)
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.
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Rezistence blýskáčka řepkového (Brassicogethes aeneus Fabricius, 1775) k různým druhům insekticidů
Tóth, Pavel
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.
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