National Repository of Grey Literature 237 records found  beginprevious130 - 139nextend  jump to record: Search took 0.00 seconds. 
Soil organic matter dynamics at reclaimed and unreclaimed post-mining sites
Bartuška, Martin ; Frouz, Jan (advisor) ; Borůvka, Luboš (referee) ; Vopravil, Jan (referee)
Soil organic matter dynamics at reclaimed and unreclaimed post-mining sites The subject of this thesis is to explore soil organic matter sequestration in post-mining soils and its relation to other ecosystem properties. The results of this study are summarized in four manuscripts, which have either been published or submitted for publication in international journals. On freshly mined-out overburden measurements of respiration revealed that the deep microflora community may substantially contribute to the microbial community in soil heaps, especially during early stages of succession and such influence early stages of pedogenesis. Microscopic observations also indicated massive breakdown of the sediment implying decomposition of fossil organic matter. For study of accumulation of soil organic matter, associated changes and interactions between chemical and biological soil properties over time, data from sets of plots of known different age(chronosequence) amended by data from repeated measurement after an extended period, allowed us to observe actual changes in soil chemistry, the carbon stock and soil properties. By this combination of these methods two separate studies were conducted at post-mining sites near the town of Sokolov in the Czech Republic (1999 and 2010). Soil pH decreased with site...
The role of soil macrofauna in organic matter decomposition and stabilisation
Špaldoňová, Alexandra ; Frouz, Jan (advisor) ; Tajovský, Karel (referee) ; Smrž, Jaroslav (referee)
Slowdown of plant litter decomposition is one of the many ways how to increase the amount of organic matter in soil and thus contribute to both the restoration of organic matter in soil and reduction of the amount of carbon dioxide in the atmosphere. Here we focused on the long-term effect of soil macrofauna on organic matter decomposition and stabilization. In two long-term microcosm experiments, common isopod (Armadillidium vulgare) greatly affected both leaf litter decomposition and organic matter chemistry. Microbial decomposition was lower in excrements than in litter or unconsumed leaf fragments. At the same time, moisture and temperature fluctuations and addition of nutrients increased decomposition much more in litter than in the excrements. Chemical analyses revealed preferential loss of polysaccharide carbon and accumulation of lignin with some modification to aromatic carbon in excrements when compared to litter; the two substrates also differed in lignin quality. Additionally, we observed that phenolics content in leaf litter is considerably affected by both microbial and isopod feeding activities. In the third long-term microcosms experiment, we compared consequence of bioturbation of the epigeic earthworm (Lumbricus rubellus) and mechanical mixing of organic matter into soil on carbon...
Analysis of air pollution in Ostrava: operation of industrial enterprises
Pěčka, Petr ; Hůnová, Iva (advisor) ; Frouz, Jan (referee)
Air pollution is one of the major environmental issues. It can cause adverse health effects such as cancer, cardiovascular diseases and high mortality rates. High population density is a huge contributory factor of air pollution in cities and urbanized areas. The third biggest city of the Czech Republic, Ostrava the subject of this thesis, is one of the most densely polluted areas of the country. The main air pollutants of concern are suspended particles and poly aromatic hydrocarbons. Ostrava's high proportion of heavy industry is a major source of air pollution compared to the rest of the Czech Republic. Other sources of air pollution are transport, local heating and possibly a pollution transfer from a neighboring industrial region in Poland. This thesis deals mainly with long term time series, including air pollutants (PM10, SO2, NOx), and meteorological variables. Information about the opening and closing of industrial plants can be considered as an added value to this work. The purpose of this data thesis is to compare the concentration levels before and after the closing or opening of particular industrial plants in the city of Ostrava during the last 35 years. So far no one has utilized these data sets for comprehensive analyses. Key words: Urban area, Emission, PM10, SO2, Industry
Soil chemical and microbial properties in reclaimed and unreclaimed grasslands
Čížková, Barbora ; Frouz, Jan (advisor) ; Cepáková, Šárka (referee)
For successful restoration of unstable ecosystems in the dumps recreating a fully functioning lan dis needed. Dump substrates often have poor grain composition, extreme pH or are toxic. They also lack important recent organic matter, which improves the overall quality of the soil and is therefore necessary for the development of quality and fertile soil. Therefore, restoration of ecosystems in the dumps is initially very slow. A number of reclamation measures was invented to accelerate this process - for example, heaping up of topsoil to dump substrates. With organic matter present in the topsoil soil formation is faster and often with their physical and chemical properties differ significantly from then developed soils. There has already been number of works written considering development of soils on the Velká podkrušnohorská výsypka so far, none of which, however, did not affect grasslands. The aim of this work was to obtain complete information about the development of chemical and microbial properties of soils that were recultivted by reclaimed topsoil and grassed and then to compare them with developments in the areas of overgrown spontaneous succession. It was found that the total carbon content increases with time only in the reclaimed areas and maximum of the increase is in the depth of...
Correlation of changes in mycorrhizal community and diversity of rare species on abandoned fields
Svobodová, Martina ; Münzbergová, Zuzana (advisor) ; Frouz, Jan (referee)
Economic and social changes of the last 20 years have led to many places to leave a large number of agricultural fields. At present, the efforts to restore species-rich grassland communities in these abandoned agricultural fields. Abandoned fields are seen as potential habitat for endangered species of semi-natural dry grasslands. Currently, a large effort to restore them back to the species-rich dry grasslands. Due to the long-term agricultural practices degrade soil communities and thereby lose their original function in abandoned fields. For the restoration of agricultural areas under cultivation back to the species-rich dry grasslands appear to be a key factor in arbuscular mycorrhizal fungal communities. The negative effect of agricultural practices on AMF communities has serious implications for the diversity and structure of plant communities of abandoned fields. Therefore, the aim of this work understanding the importance of AM fungi for possible restoration of plant communities on abandoned agricultural fields. In this paper we compare two different types of inoculum (grassland, fallow land ) to support the survival and growth of target plant species of dry grasslands on a abandoned field two approaches - sowing and planting. We assumed that the inoculum of species-rich dry grasslands...
Secondary metabolites, allelopathy and their significance in the invasion of Heracleum mantegazzianum
Jandová, Kateřina ; Dostál, Petr (advisor) ; Frouz, Jan (referee) ; Valterová, Irena (referee)
One theory concerning the invasiveness of exotic plants suggests that they exude allelopathic compounds that are novel in areas being invaded. Here, I tested for allelopathic effects of root exudates of the invasive plant Heracleum mantegazzianum (giant hogweed) in a series of experiments both in vitro and in the garden, and compared them with effects of its native congener H. sphondylium (common hogweed) and two less related native species. Moreover, I addressed intraspecific variability of allelopathy by comparing effects of 41 different maternal lines of H. mantegazzianum sampled from several areas and populations within the Czech Republic. Not only the effects, but also the identity of allelopathic compounds was investigated. In order to test also for the interaction of allelochemicals with soil microorganisms, I analysed the composition of soil microbial communities expressed as phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) together with nutrient conditions and light availability at invaded sites in the Czech Republic. The results show that H. mantegazzianum is able to exert phytotoxic effects in vitro as well as in the garden experiment; however, its effects did not differ from the inhibition caused by the native species tested. Variation partitioning among areas,...
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...
Obnova druhově bohatých luk na výsypkách po těžbě uhlí, vliv růyných technik a velikosti obnovované plochy
Kolářová, Petra ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Common problems and characteristics of sites affected by the mining are land occupation, pollution, land degradation, hydrologic changes and landscape change what belong to the major environmental problems in many countries. Despite the regulation prescribed by the Mining Act which brought significant progress in post mining land reclamation, emphasise mostly in recovery of production capability of landscape, many recent studies state it may not be so effective in restoration of diversity and ecosystem services. In order to properly assess newer approaches in spoil heaps recultivation our research is focused on the restoration of species rich meadows using near-nature methods, specifically the transfer of turves and seeds-containing hay transfer supported by management (mowing and mowing with mulching). Additionally, the research is focused on influence of the plot size on restoration success and on effect of management on soil development. Both of the applied near-nature methods of species rich meadow recultivation are effective in species provisioning and thus succession acceleration. More successful is the method of transferred turves where it was possible to establish more than 60% of the species from the donor site. The species richness on sites and its spreading is dependent on implemented...
Interactions of soil fauna and vegetation during sucession on spoil heaps after brown coal mining
Roubíčková, Alena ; Frouz, Jan (advisor) ; Smrž, Jaroslav (referee) ; Tajovský, Karel (referee)
Earlier research on the spontaneous succession on spoil heaps near Sokolov, NW Bohemia, has documented major changes in vegetation during middle successional stages, that correspond with occurence of some groups of soil macrofauna (earthworms and wireworms - Elaterid beetle larvae). We have tested the interactions between these soil animal groups, plants and soil in several experiments: In two laboratory and two field experiments earthworms positively affected growth of late successional plants (Arrhenatherum elatius, Agrostis capillaris, Centaurea jacea, Festuca rubra, Plantago lanceolata, Lotus corniculatus, and Trifolium spp.), during the laboratory experiments a decrease in soil pH and increase in microbial respiration, oxidable C, total N, and exchangeable P, K, and Ca content was detected in presence of earthworms. In a laboratory experiment earthworms also negatively affected germination of small seeds in comparison with large seeds. Concurrently, earthworm performance is affected by the biotic and abiotic conditions at the site; their biomass increased when kept in pots at sites 28 and 48 years old with high tree coverage and decreased in pots at younger sites. Wireworms negatively affected biomass of Calamagrostis epigejos in both laboratory and field experiment, their reduction in field...
Interactions between plants and soil biota and effect of energetic crops on these interactions
Heděnec, Petr ; Frouz, Jan (advisor) ; Pergl, Jan (referee) ; Mortimer, Simon (referee)
My PhD thesis is focused on study of plant-soil interactions. Chapter 1 is focused on general introduction to the interactions between plants and soil biota in terms of relationships between soil organisms and aboveground biomass as well as root biomass. Chapter 2 is focused on food interaction of Folsomia candida and soil microscopic fungi (Penicillium chrysogenum, Penicillium expansum, Absidia glauca, and Cladosporium herbarum). Fungi were grown separately on Petri dishes or on different litter type (oak, alder and willow) separately as well. Laboratory experiments showed that food preference was more influenced by different litter types than fungal species. In chapter 3 was studied long-term production of hybrid sorrel and its effect on the composition of the soil meso and macrofauna, basal soil respiration, microbial biomass and composition of cultivable fraction of soil microscopic fungi in comparison with oilseed rape and cultural meadow. There was found that long-term production of hybrid sorrel affects the composition of soil fauna, while the microbial activity of the soil was more affected by agriculture practices, especially tillage. In chapter 4 was studied the effect of native (Salix viminialis and Phalaris arudinacea) and introduced (Reynoutria sachalinensis, Silphium perfoliatum and...

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