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Lichens and eutrophication
Jadrná, Iva ; Svoboda, David (advisor) ; Malíček, Jiří (referee)
Eutrophication is a process of organic nutrients enrichment in an ecosystem, especially nitrogen and phosphorus. This bachelor thesis is dealing with the influence of eutrophication on lichens, especially with the effect of nitrogen compounds in the air and the effect of the combination of nitrogen compounds with phosphorus on epiphytic lichens. Eutrophication is defined and information is provided on changes in abundance and diversity of lichen cover. The mechanisms of eutrophication tolerance in lichens are also described. Key words: lichens, epiphytes, eutrophication, ammonia, ammonium ions, nitrogen oxides, phosphorus
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Management of the protected areas in sand habitats
Šímová, Kamila ; Münzbergová, Zuzana (advisor) ; Pivnička, Karel (referee)
Management of the protected areas in sand habitats is a thesis interested in the management techniques in relation to the sand habitats. In Central Europe, sand habitats are a rare and threatened grassland biotope. In the Czech Republic, we can find natural sand habitats localities, which are threatened by the human impact and anthropogenic localities, which tend to increase in number. Diversity and richness of the natural stands is gradually decreasing due to the high sensitivity of the species to any change of the local environment. These changes are mainly caused by the human activity. The negative effects are eutrophication, acidification and accelerated succession. The management of the sand habitats should contain many succession regulation tools and techniques reducing eutrophication. I discuss mowing, removal of the expansive plant species, pasturage, burning and sod disturbance or sod cutting. Each of these methods has specific impacts on the ecosystems and the best management combines them to achieve the best performance of the protected area. The most preferable method seems to be sod cutting, due to its high effectivity. However, there are many questions about sod cutting that need to be answered in a future study, such as how the population dynamics after sod cutting will look like, what the...
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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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Changes in epiphytic lichen biota in the Czech Republic with emphasis on current situation
Hronová, Nikola ; Malíček, Jiří (advisor) ; Palice, Zdeněk (referee)
During the last two centuries a significant change of lichen communities has happened in the Czech Republic. Important factors which had influencing the lichen biota in the past and recently are summarized in this bachelor thesis. Acid rain caused by high imissions of SO2 a NOx was the most important factors of change of species and remaining acidification of substrates is still influencing lichen communities. Until the end of 80's of 20th century acid rain was a dominant factor influencing lichens. Afterwards, thanks to drop of its intensity in 90's of 20th eutrophication and availability of nitrogen in landscape became dominant influencing factors. All these factors mainly affected the communities of macrolichens, and especially cyanolichens to such an extent that some species in the Czech Republic became extinct. Recently the increasing availability of nutrients has been supporting the spread of nitrophilous species. Due to decrease of SO2 emissions to values from the end of 19th century some areas have been recolonized and some endangered species have returned. The transformation of lichen communities has also been significantly affected by forest management and land use. Based on changing climate and change of natural habitats a further decline mainly of suboceanic species is expected. A more...
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The Project of a Small Water Reservoir in the Níhov Cadastral Area
Matoušek, David ; Doležal, Petr (referee) ; Menšík, Pavel (advisor)
Diploma thesis ‚The project of a small water reservoir in the Níhov cadastral area’ has goal to introduce to reader the small water reservoir as the important landscape element. Small water reservoir is cornerstone of local ecological stability, which has important income for microclima in the closes surrounding. Furthermore, the function of constant improvement water quality in the basis or contribute to increasing of ground water level. Thesis is divided into two parts. In the first theoretical part thesis describes the topic of small water reservoirs briefly. The first part shortly describes the details of designing process or inner process within the reservoir. In the second practical part is created basic project documentation based on the data collected and measured in the affected area. The project was created in cooperation and upon request of investor the representation of the village Níhov.
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Ecological biomonitoring of peatlands - the NCV index, acidification and eutrophication
Henková Mauleová, Lucie ; Neustupa, Jiří (advisor) ; Šťastný, Jan (referee)
Biomonitoring is a method of ecosystem properties determination based on its biological properties, especially composition of the biota. Based on various aquatic-oriented biomonitoring systems, it is possible to quantify, for example, water purity or trophic index for water management purposes or to characterize the ecological status of the ecosystem for scientific and conservation purposes. While water quality-oriented biomonitoring systems are widespread and routinely used, ecology state-oriented (quantifying qualities like succession stage or stability) are less exploited and their wider use in the future could help understanding and management of some aquatic ecosystems. One of the ecology-oriented biomonitoring systems is NCV index (natural conservation value index) oriented to wetlands which it evaluates through their desmid biota, measuring species diversity, rarity of represented species and ecosystem maturity for which they are typical, and rarity of represented species NCV index aims to describe the value of the ecosystem in terms of its replicability.
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The impact of eutrophication on fish in running waters
Jeníšová, Karolína ; Horká, Petra (advisor) ; Frouzová, Jaroslava (referee)
Eutrophication belongs among be the most serious factors threatening freshwater ecosystems. Eutrophication is a result of excessive nutrient loading which comes mostly from both the point-source and diffuse pollution and agriculture, increased sediment loading from soil erosion, but also due to a presence of various types of impoundments, which, particularly in some areas, represent a significat part of nutrient supply. Although the effect of eutrophication on freshwater fish communities has been thoroughly studied in standing waters, very little attention has been paid to running water ecosystems. Among the processes with the most pronounced impacts on fish communities are increased phytoplankton growth and loss of macrophytes, low oxygen levels or anoxia, occurrence of toxic forms of nitrit and ammonia and elevated turbidity and subsequent light reduction. Whilst the diversity of fish communities is not usually affected, changes in structure of fish communities and decreased ecological quality has been detected with the increasing level of eutrophication. The most sensitive fishes are salmonids as they have high oxygen demands and are very sensitive to a toxic forms of nitrogen. Moreover they are visual predators highly affected by the increased turbidity of water environment. Percids are mainly...
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The influence of agricultural activities on the stream water quality in natural reservation
NOVOMĚSTSKÁ, Markéta
The aim of this thesis is to evaluate the impact of agricultural activity on hydrochemical parameters of surface waters in connection with the occurence of specially protected species within the surface waters of a monitored area. A model was chosen for the evaluation of the situation - Bedřichovský potok, which is located in Novohradské hory. The river consists of lower and upper sub-waters. Forest management is applied within upper sub-basin, while agricultural management on arable land, meadows and pastures is used in the lower sub-basin. The monitored parameters were indicators of eutrophication of surface waters: Nitrate nitrogen (N-NO3-), Phosphate phosphorus (P-PO43-), and conductivity of undissolved material (NL105). The results showed that the agriculture management (especially on arable land) burdens the soil with nutrients and consequently erosion enters the substances, bringing them to the surface and ground water as a result. There was an increase of substances in the water after rain.
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The Effect of P Enrichment on Exudate Quantity and Bioavailability - a Comparison of Two Macrophyte Species
KUBEŠOVÁ, Jaroslava
A study on rhizodeposition rates and rhizodeposits bioavailability (microbial respiration, N mineralization and phosphatase activity) of two macrophyte species with different life strategies (stress-tolerator and competitor) was conducted. Research was carried out in tropical marshes of Belize; results from the field were supported by 13C partitioning mesocosm study. The stresstolerant Eleocharis spp. released more C from roots than Typha domingensis and this C was more biodegradable. The two species responded to P enrichment differently. While Eleocharisspp. invested more assimilated C to the belowground (roots, rhizomes and rhizodepositions) after P fertilization, in T. domingensis the belowground C investment decreased. The effect of plant species was larger than the effect of P enrichment. Eleocharis spp., adapted to growth under low nutrients, invests more carbon into exudation a promotion of its microbial communities in the rhizosphere while competitive T. domingensis spends more fixed C on its own growth and metabolism.
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