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The Global ETD Search service is a free service for researchers
to find electronic theses and dissertations. This service is
provided by the
Networked Digital Library of Theses and Dissertations.
Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Biochemické markery funkce půdního mikrobiálního společenstva a vliv antropogenního stresu / Biochemical markers of soil microbial community and functioning and antropogenic stressKukla, Jaroslav January 2020 (has links)
The soil microbial community has a major impact on ecosystem processes on a global scale. Anthropogenic stress has a significant effect on the composition, biomass and activity of the microbial community. In addition, this effect depends not only on the anthropogenic activity, but also on the environmental conditions. Modern analytical and molecular methods, including the use of biochemical markers, can be well used to monitor changes in the microbial community. These methods do not monitor the community directly, but detect the substances that are secreted and transformed by microbes and, last but not least, those that are part of them. The amount of these biochemical markers reflects the biomass, condition and taxonomic composition of a particular microbial community. In the presented work, these markers were used to monitor the response of microorganisms in various ecosystems which are affected directly or indirectly by human activity. The results of the dissertation are presented in four articles. Three of them have been published in international journals with IF and one is prepared in the form of a manuscript for publication. The first publication presents the results of research exploring the impact of traditional agriculture in Papua New Guinea on the soil microbial communities, soil...
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Obnova rostlinných společenstev po odstranění invazního rodu Reynoutria / Restoration of plant communities after eradication of invasive Reynoutria speciesMártonová, Marie January 2010 (has links)
Reynoutria spp. rank among highly invasive taxa in the Czech Republic. Therefore, a considerable effort is focused on its eradication. This is usually done by application of non- selective herbicide based on glyphosate. However, only little is known about the spontaneous recovery of the native vegetation after the eradication, as well as whether the restoration can be facilitated by additional management. In my master thesis I (i) describe the process of restoration after Reynoutria spp. eradication, (ii) evaluate the influence of factors which could potentially inhibit the succession (such as glyphosate, allelopathy, changes in soil conditions due to Reynoutria spp. invasion), and (iii) evaluate the influence of native-species seed addition on establishment of target plant communities. The process of vegetation recovery was followed on 17 sites in a forest and in ruderal forest-free area from 2007 to 2010. Over the three years of the study, the sites in the forest- free area were covered by diverse vegetation, secondary succession on sites in a forest progressed more slowly. Any soil changes were detected. The process of succession was limited probably because a dead biomass was left on the sites after the eradication. The seed addition was also not crucial for the restoration of plant communitites.
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Druhová diverzita pastvin a luk na malé prostorové škále / Species diversity of meadows and pastures on small spatial scaleBartoš, Michael January 2011 (has links)
Grazing seems to be not only means of conserving species diversity of grasslands but also - in many cases - of its increasing. This thesis tries to find out the mechanisms of grazing that result in increased or decreased species diversity. The experiment was proceeded in Slupenec, a part of Český Krumlov, where horse pastures are situated. In order to compare grazing and mowing I collected phytosociological data from plots 1 x 1 mš. I also collected data about soil moisture, composition and pH in order to find out the main gradients in vegetation. The vegetation data from plots 20 x 20 cmš were collected before and after grazing on three pasturelands. In the chosen locality, higher level of plant species diversity have been proven on pastures in comparison with meadows. There is significantly higher percentage of plots contributing to the higher level of ß diversity on pastures than on meadows. At the same time the variability of vegetation was in most cases explained by the categorial variable pasture / meadow. Concerning selectivity of grazing, it has been proven that horses prefer grazing on species with greater cover abundance. The plots with lower rate of grazed species have got higher ß diversity. In terms of functional traits of plants, it has been proven that higher percentage of no-rosette...
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A Middle Woodland House and Houselot: Evidence of Sedentism from the Patton Site (33AT990), the Hocking River Valley, Southeastern OhioWeaver, Sarah A. January 2009 (has links)
No description available.
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Das Auftreten acidophiler/calcifuger Pflanzenarten in Kalk-Halbtrockenrasen / The occurence of acidophile/calcifuge plant species in semi-arid calcareous grasslandsFühner, Christoph 02 November 2005 (has links)
No description available.
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