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Thermoregulation in ant genus Formica, an individual vs. colony conflict
Kadochová, Štěpánka ; Frouz, Jan (advisor) ; Dauber, Jens (referee) ; Domisch, Timo (referee)
This thesis deals with thermoregulation in red wood ants, in Formica rufa group. Our aim was to better understand the mechanisms by which red wood ants maintain thermal homeostasis in their nests. Red wood ants are known to keep high and stable temperatures in their nests from spring to autumn. Most emphasis is placed on the role of the nest mound as a solar collector or on a heat production by microbial community present in the nest material. However, some researchers believe that wood ants are able of active nest thermoregulation in which they can affect the nest temperature by behavioural reactions, mainly by sun basking, increased metabolic heat production or heat transport. The thesis consists of three research articles. The first one is focused on the timing of thermoregulation in red wood ants, the second one investigates in more detail one specific aspect of red wood ant thermoregulation - a sun basking behaviour. These two papers provide data from long-term field observations and experiments. The last paper is based on laboratory experiments where we tested a hypothesis resulting from field observations. Thanks to the field research we found out that ant activity (traffic on ant trails) significantly correlates with nest temperature; once the activity decreased the thermal homeostasis...
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Key factors in soil organic matter accumulation
Vindušková, Olga ; Frouz, Jan (advisor) ; Borůvka, Luboš (referee) ; Šarapatka, Bořivoj (referee)
Soil organic matter (SOM) is highly important for soil quality and the global carbon cycle. SOM content is influenced by a complex interplay of many different factors such as time, climate, parent material, vegetation, and others. The effect of time is often studied using the chronosequence approach using a set of study sites differing in age but comparable in other soil-forming factors. The effect of other factors can be studied by comparing two or more chronosequences. An important assumption of these approaches is that the SOM quantification methods produce comparable results both among sites of each sequence and among different sequences. In this thesis, I explored the key factors in SOM accumulation and dealt with SOM quantification methods. I studied SOM accumulation in two model situations - in post-mining sites after open-cast coal and oil shale mining and in landslides in the Western Carpathians. The results of this thesis are summarized in one book chapter accepted for publication and four papers, out of which three have been published and one is prepared for publication in an international journal with impact factor. The key factor affecting the rate of SOM accumulation after a major disturbance is time. The accumulation rates found in the first 40 to 100 years in both post-mining sites...
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Factors influencing vegetation establishment during spontanous succession in basalt quarries
Petrů, Anna ; Frouz, Jan (advisor) ; Roubíčková, Alena (referee)
Mining and construction industry is a major environmental disturbance creating habitats with extremely coarse material: gravel, cobbles and boulders. Simultaneously, there is an increasing interest in using spontaneous succession during restoration processes on those areas. This leads to a question if vegetation can establish on such coarse substrates. This project assessed the vegetation establishment on substrates with different grain size as well as the hydrological limitations of those substrates. The aim of this study was to find substrate moisture characteristics supporting vegetation establishment. Four herb species (Koeleria macrantha, Epilobium angustifolium, Artemisia campestris var. campestris and Poa nemoralis) typically occurring on xerothermic basalt rocks were sowed on basalt construction aggregates (0-4, 2-4, 4-8, 8-16, 11-22 and 32-63 mm). There were also made mixtures of coarse aggregates (4-8, 8-16 and 11-22 mm) as a base with 10% or 50% additive of fine aggregates (0-4 mm). The final number of individuals, aboveground and belowground dry biomass were measured and subsequently specific leaf area (SLA) was calculated. They were also measured substrate moisture characteristics: field capacity (PVK) and wilting point (BV) from which available water content (ODV) was obtained as...
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The effect of artificial drainage and subsequent restoration on carbon stock and water retention in a watershed
Kešner, Michal ; Frouz, Jan (advisor) ; Kuráž, Michal (referee)
In the 1980s, the meadows around Senotín in southern Bohemia were drained by subsurface pipe drainage. After considerable drought in 1992, this area was subjected to extensive research. In 1995, a part of the drained area was revitalized. The drainage pipeline was interrupted by seven clay screens, over four of them country lanes and shallow depressions were built. The research of this site was realized after revitalization and focused on the water regime of the soil and on the physical, chemical and biological properties of the soil. This thesis describes the state of water regime, physical and chemical parameters of soil in undrained, drained and revitalized areas 20 years after revitalization and compares them with data from research performed in the past. The rainfall and runoff data was measured in the catchment area, and soil samples were collected in the regular network. Research has shown that between 1998 and 2014 there has been a reduction in river runoff. However, a more detailed data analysis has identified the vegetation transpiration as the main factor. There has been no increase in soil retention or soil moisture. None of the investigated soil parameters on the revitalized area (bulk density, carbon and nitrogen content, C:N ratio, pH, and conductivity of the aqueous extract) is...
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European black alder (Alnus glutinosa L. Gaertn.) in symbiosis with Frankia and their growth on post-mining heap soils
Buchbauerová, Lucie ; Frouz, Jan (advisor) ; Roubíčková, Alena (referee)
Alder (Alnus glutinosa L. Gaertn.) is a species of a pioneer plant usually colonizing sites in the early stage of ecological succession, such as spoil heaps after open-cast brown coal mining in the Sokolov mining district in north western Bohemia, Czech Republic. These spoil heaps are very poor in nutrients available for plants, yet alders grow in a mutualistic relationship with actinomycetes Frankia, which live in root nodules of the alder plants. Frankia are able of fixing atmospheric nitrogen (N2) to ammonia (NH3) molecules, which can be then assimilate by alders, via enzyme nitrogenase. Thus, in the early stages of succession, alders have a competitive advantage to other non- fixing plant species living only on nitrates (NO3 - ) and ammonia ions (NH4 + ) present in soils. The aim of this study was to conduct and assess two greenhouse experiments. The first experiment studied the response of alder growth to presence of Frankia and arbuscular mycorrhizal fungi of order Glomerales. The performance of alder growth was significantly higher when alders were inoculated with both Frankia and mycorrhizal fungi in comparison to when alders have grown on their own or only with a mycorrhizal symbiont - both on 14 and 60 years old soils from Sokolov mines. In the second experiment, soil pH and iron (Fe) and...
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The effect of N fertilization on plant growth during primary succession
Müllerová, Věra ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Nitrogen as the fourth most educated element of living organisms and the limiting factor of the aquatic and terrestrial ecosystem is still a major problem for scientists around the world. Today, developed countries are able to store their inputs in the form of depositions in the same values, but there is a question of long-term effects of chronic nitrogen add-ons. The aim of the thesis is to compare the effect of long-term and one-time fertilization on various plant species, especially on grass and nitrogen fixation plants in relation to the age of the soil on which they grow. This connection will be investigated by the ANOVA method in a practical experiment on selected plants growing on different old soils that have been or have not been fertilized for long periods with nitrogen. As model organisms, I chose a nitrogen fixing device, Lotus corniculatus, and Festuca rubra an unstable plant, which is also a representative of the grass. One-off fertilization had a positive effect on the growth of above-ground biomass on all plants. We have a different impact according a type of plant on long-term fertilization. In this case, I recommend more detailed testing of a wider sample of plants.
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The effect of drainage and restoration on vegetation of wet peaty meadows.
Krejčová, Jana ; Frouz, Jan (advisor) ; Syrovátka, Oldřich (referee)
The aim of this thesis is to summarise the current knowledge of the effects of amelioration entervention especially drainage on wet meadow vegetation. First part of this thesis consisting of literature review of scientific papers and other studies summarises the influence of water on soil. It describes how the loss of water and degradation of soil influence the plant communities of wetlands. Drainage of wetlands was very common due to the intensification of agriculture in the past. The amelioration intervension resulted in the loss of peat horizon in soil and reduction of biodiversity. This review explains the reasons to common drainage in the past. In conclusion of the review, the thesis evaluates the efficiency and possibilities of wetland biotopes restoration. The second part of the thesis describes the specific research in the village Senotín (running between 2015 and 2016) which compared the results of the studies from 1996 and 2016. The effectiveness of restoration was examined and compared on the basis of phytosociological images of vegetation which are presented on three different types of areas.
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Model optimizing of the biogas plant operation after testing operational phases
Raška, David ; Matějíček, Luboš (advisor) ; Frouz, Jan (referee)
Biogasplants are installations for converting of biomass to produce biogas, which is a valuable energy source if a proper management of ananaerobic process is kept. In the Czech Republic are mainly agricultural biogas plants. This workis focused on evaluation of data obtained from a specific biogas plant, which islocated in the town Úpice. This plant processes biodegradable waste. Data are evaluated qualitatively, also with use of cluster analysis using statistical program R as well as by a proposed linear regression models in Matlab software. Results were applied for suggestins of several measures for the management of biogas plant and for creation of non-linea rregression model, which can be further developed. . Keywords: Biogas, plant, anaerobic, fermentation, biodegradable, waste, data analysis, differential model
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Wood ants of genus Formica as important ecosystem engeneers
Jílková, Veronika ; Frouz, Jan (advisor) ; Tajovský, Karel (referee) ; Bonkowski, Michael (referee)
This thesis consists of one chapter accepted for publication in a book and four papers published in international journals with impact factors. All of the contributions deal with the role of wood ants in energy and nutrient fluxes in forest ecosystems. Wood ant nests are known as hot spots of carbon dioxide (CO2) production and are also thought to affect methane (CH4) flux. Stable high temperatures are maintained in ant nests even in cold environments. This study is focused on quantification of CO2 and CH4 flux in wood ant nests, contribution of ants and microbes to CO2 production, properties of nest material that affect CO2 production and the role of ants and microbes in the maintenance of nest temperature. The research was conducted in temperate and boreal forests inhabited by wood ants (Formica s. str.). Gas fluxes were measured either by an infrared gas analyser or a static chamber technique. Ants and nest materials were also incubated in a laboratory. Material properties potentially influencing CO2 flux, such as moisture, nutrient content or temperature were determined. According to the results, CH4 oxidation was lower in wood ant nests than in the surrounding forest soil suggesting that some characteristics of ant nests hinder CH4 oxidation or promote CH4 production. Wood ant nests clearly are hot...
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Various methods of soil transfer and inoculation in restoration ecology
Hurychová, Hana ; Frouz, Jan (advisor) ; Roubíčková, Alena (referee)
Soil translocation is a method used in restoration ecology to either salvage habitats threatened by human activity or to restore disturbed habitats. There are various factors affecting the success rate of translocation operations which include the proper selection of a receptor site, method of soil manipulation, soil stockpiling and adequate aftercare. Different methods of soil stripping distinct in their success rates and application for use in habitat restoration, mainly in regards to their effect on the resultant community composition and financial costs. Translocations can result in decrease of biodiversity, but may be a viable option for locations of high conservation value where conservation in situ is not possible, allowing for quick restoration of mature ecosystems. Thorough surveys prior to and after the operation and sufficient allocation of resources are a key factor for successful translocation of soils and the associated biota. Additional research in the fields of invasions, comparison of methods and data analysis of translocation projects may improve the utilization of this technique in the future.
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