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Carbon sequestration by forest ecosystems in canging climate.
Hlaváčková, Lucie ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The global carbon cycle is in the focus of the scientists' interest, because understanding carbon sinks and their relationships can show the solutions of problems related with increasing CO2 concentration in the atmosphere in the future. I focused on the role of forests ecosystems in this carbon cycle. All forests cover almost one third of the Earth's land area. By photosynthesis they bind big part of atmospheric carbon to their biomass. Sink strength of forest can differ according to the type of biome, forest stand age and actual climatic conditions. Forest biomes can be generally divided according to the latitude to three groups: tropical forest biomes, temperate forests and boreal forests. The size of carbon stock decreases in this order. Other parameters, such as net primary production and respiration differ in dependence on the particular ecosystem. Tropical rain forests represent great carbon stock, but their deforestation causes massive C emissions back to the atmosphere. Boreal forests aren't considered as important carbon sink, but they influence local climate. Some speculations can also appear about the old forests. It is possible to find authors, who claims, that old forests are no more carbon sinks, so that their carbon balance is neutral. Many surveys prove that they bind less carbon...
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Issue of Deer ked from the Perspective of Monitoring
Bjelková, Karolína ; Horák, Jakub (advisor) ; Holuša, Jaroslav (referee)
This bachelor thesis concerned issue of deer ked from the perspective of monitoring to wild game on the skin pulled from hunted animals and human specimens showing two locations for themselves binding - Mala Morava and Libava. Deer ked is hematophagous ectoparasite of cervids, which in recent years expanded its area of occurrence from Europe to America. The aim of this study was to determine the prevalence and intensity of infection and to evaluate the influence of the nature habitant, weather factors or determination of sex by the host.For identification were examined 95 animals in body area, on the nape and genitals. The overall intensity of the attack were analysed in relation to age, gender, weather and landscape characteristics of point of capture. Results of occurrence of deer ked are described and evaluated demostrate the prevalence of infection almost 100%, but the rate pressure of animals ranged from 0 to 10 deer ked 100 cm-2. The highest occurence was found in males, and simultaneously was also associated wit a host of areas on the body where the most parasites were found on the genitals, 7-10 pieces. The significant influence had the temperature. The influence of rainfall was insignificant. It was found that the highest occurrence is on the animals, which use habitant fields and meadows, probably due to positive effects of solar radiation and thereby raise the surface temperature of the skin. Localization of body aeas can be used to setting means for effectiveness insecticide against these parasites.
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Issue of deer ked from the perspective of efficiency of repellents
Hallová, Elen ; Horák, Jakub (advisor) ; Lukášová, Karolína (referee)
This bachelor thesis summarises information about hematophagous Deer ked (Lipoptena cervi), which attacks animals living in the wild and also humans. This topic is interesting particularly because of the global threat to human by haematophagous insects while continuous expansion of its distributional range. There is described external morphology and sexual dimorphism using electron microscopy. Due to an increased cases of incidences of Lipoptena cervi on humans there is description of production of a natural insect repellent and test of its effectiveness at selected sites outdoors with the help of test methods on human volunteers. Briefly, the thesis analysed the possibility of transmission of infectious diseases Lipoptena cervi. Biorepelent repeled Lipoptena cervi 100% even though it is a hematophagous, Lipoptena cervi has not yet been established as a carrier of pathogens, infections and other diseases on humans.
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The benefits of the proposed methods of calculating the financial damage to the water feature of the forest, which was established in direct connection with the location and the realisation of the buildings
Bureš, Petr
Problem situations in damage to forests as a result of construction activities is the total of its quantification, because of not only to damage to the forest and the land intended for the performance of the function of the forest, but also to damage to the water feature of the forest. The emergence of the crop damage and forest grounds occurs at the same time damage to the management. Broken water conditions on the forest grounds, inter alia, that the environmental damage (or one of its components), are also material injury for the owner of the forest, because it directly affect the amount of the additional costs linked to its management in the forest. The existing decree MZe ČR no. 55/1999 Coll. on the method of calculating the amount of loss or damage caused to forests assesses only the injury or damage to the forest and the land intended for the performance of the functions of the forest, but does the forest and its other non-production function as a forest ecosystem. The damage (the material injury) on the water feature of the forest is not the above mentioned decree dealt with.
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Problematika deforestace brazilské Amazonie
Fialová, Andrea
The main aim of this bachelor thesis is an evaluation of deforestation issue in Brazilian Amazon. The importance and distribution of forests on the planet and elucidated term deforestation and its involvement to global problems and the definition of main causes and consequences of deforestation are explained in the theoretical part. Specific part first characterizes Amazon rainforest and his importance, geographic location and climate conditions. Then it summarizes causes and consequences which are caused by deforestation in this region and show the evolution of Brazilian government policies and their influence on rainforest. Finally, information obtained, are evaluated and there are suggested solutions, especially in a relation to particular causes of deforestation.
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Content of cesium-137 in forest ecosystem in selected locations
SEBEROVÁ, Pavlína
The human and the whole environment are irradiated from the different sources (natural or artificial). The natural sources of radiation are cosmic and sun rays or the natural radiation of the Earth. The artificial sources mean cyclotrons, X-rays, particle accelerators, nuclear reactors and others. Natural cesium is located very rarely on Earth, but it has many artificial isotopes (for example Cs-137 and Cs-134). The Cs-137 is an artificial isotope produced by human. The first source of the Cs-137 became the nuclear tests and attacks used in the World War Two. In the 1960s (related a study of nuclear weapons) there were found out storing of Cs-137 in the surface soil layers. Even the peaceful use of the nuclear energy could cause the nuclear crash accompanied by a leakage of radioactive substances. The most tragic crash was an explosion of the nuclear power station Chernobyl in Ukraine. That crash contaminated the whole Ukraine and close states, but also Scandinavia. The spread of the Cs-137 depended on the rainfall and the air flow. Human has been affected by the radioactive elements even after the long time since the crash. Forest ecosystem seems to be the place with the largest amount of Cs-137 located. The Cs-137 may get into the human body though food; it has a very long half-time (30ys), it is stored in the top soil layers and through the root system of plants gets into the plants or mushrooms. The aim of this thesis is to determine and compare the content of the Cs-137 in the selected commodities in the forest ecosystem of Šumava using semiconductor gamma spectrometry. The research question was specified: Is the content of the Cs-137 in the selected commodities of the Šumava forest area significantly different? Based on an analysis of literature and consultation with the State Office for Nuclear Safety there were chosen areas, where was the highest fallout of radioactive elements. Therefore I sampled the area called Kvilda, Zadov and Churáňov. Further locations with the commodities of the forest ecosystem are Bavorov, Svinětice and Baranaviči. There are samples of soil, moss, spruce bark, cones and lichen. Not all commodities could be collected in all locations because there were picked in a small area and not all commodities occurred there. To determine the mass activity of the Cs-137 samples I used a semiconductor gamma spectrometry. The obtained spectra were evaluated through software GAMAT. The range of the values of mass activity of the Cs-137 in all samples is between 3-700 Bq.kg-1. The highest activity was measured in soil, where values reached up to 700 Bq.kg-1. High activity was also measured in moss in Kvilda, 513 Bq.kg-1. Samples of spruce bark, cones and lichens have low values activity. It was not reached out the value of 300 Bq.kg-1. Answer to the research question is that contamination of Sumava Cs-137 in selected commodities forest ecosystem is significantly uneven.
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The Use of the Forest Ecosystem in Preschool Science Education.
BOLEHOVSKÁ, Alena
This bachelor thesis in its theoretical part deals with environmental education and its inclusion in educational process in a nursery school. Alternative ways of education and their attitude to environmental education are shown here. Theoretical part also includes available natural science literature summary. In the practical part of the thesis there is a four-part project Forest ecosystem in natural sciences in nursery school, which was applied in practise. Research questions were asked during realisation of the project. Main aim was to detect actual level of knowledge. Results of the research are presented in charts and tables.
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