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Vliv světla a sucha na fotosyntézu a vodní provoz podrostních bylin temperátních doubrav
Vitásek, Roman
Woody plants, especially trees, affects the site microclimate. With their physiological manifestations, they influence hydrological and light conditions and, consequently, the composition and abundance of species from the plant community. A dense tree layer lowers the air and even more the surface temperatures. Its mitigating effect is most pronounced on hot summer days. While transpiration lowers air temperature, trees compete with understory for water. While the shade lowers surface temperature of understory, plants, as autotrophic organisms, need enough light for their survival. Therefore, the question arises, which density of forest canopy is optimal for the survival of understory during the global change that brings along increased temperatures and elevated levels of drought. I investigated how understory herbs cope with drought under simulated sparse and dense forest canopy. The focal species, European wild ginger (Asarum europaeum L.) and liverwort (Hepatica nobilis Schreb.), were divided into four groups: two of them were fully watered and two of them droughted. Each of the water regimes were divided in two groups, simulating sparse or dense canopy of woody overstory. The physiological response of plants (such as the rate of light-saturated photosynthesis, stomatal conductance, intrinsic water use efficiency, concentration of non-structural carbohydrates and water potential) on manipulated light and drought conditions was monitored under various levels of drought stress. The mortality was always higher under deep shade than under light conditions, despite different water management strategies of stomatal regulation. The European wild ginger has characteristics of an isohydric type of plant. During drought, it copes with the negative water potential by reducing stomatal conductivity, at the expense of the ability to actively fight water stress by creating assimilates. Under favorable conditions, this species stores starch that allow it to survive even with a significantly reduced rate of photosynthesis. The liverwort is more anisohydric in its behavior. With the increasing intensity of drought and increasing transpiration, it keeps the stomata open and by active photosynthesis it creates soluble carbohydrates for the production of osmotically active secondary metabolites. It has a very low level of stored starch, which can have a negative effect during prolonged drought. The results indicate that light plays an important role for plant survival under water stress. The changing climate brings along not only increased temperatures but often increased levels of summer drought. Therefore, growing in the understory of the dense forest does not always help the plant to survive warming climate.
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Hodnocení reakce odrůd pšenice seté k suchu metodami molekulární biologie
Sodomová, Karolína
This thesis deals with the issue of drought, which is occurring more and more frequently with ongoing climate change. During longer or intense periods of drought in the agricultural landscape, significant losses in the yields of field crops can occur. Here, the effect of drought in laboratory conditions on two preselected varieties of winter wheat was monitored. It is the most cultivated crop in the Czech Republic, and therefore it is important to know the mechanism of its defense against a stressful environment. The response to stress was evaluated by molecular biology methods. Through the Real Time PCR method, the expression of selected genes was monitored, thanks to which the reactions of the Bohemia and Tonnage varieties were compared. The results show that Bohemia loses water more slowly when exposed to drought stress. At the same time, a higher expression of protective genes can be observed in the Tonnage variety. This indicates its lower tolerance to drought. It can therefore be argued that in an agricultural landscape where droughts occur more often, it will be more appropriate to grow a more tolerant variety to reduce yield losses, which in this experiment is the Bohemia variety.
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Srovnání přístupu k adaptačním opatřením na změnu klimatu v lesích ve vybraných státech na úrovni národních plánů a politik
Papalová, Alexandra
The topic of the bachelor's thesis is Comparison of the approach to climate change adaptation measures in forests in selected countries at the level of national plans and policies. In this context, the bachelor thesis deals with adaptation measures that are applied in order to mitigate the effects of climate change on forests and forestry. The bachelor thesis is written in the form of research. The thesis first deals with basic concepts such as climate change and its effects in general, the effects of climate change on forests and forestry, and adaptation to climate change. Subsequently, it deals with the characteristics of natural and socio-economic conditions and their vulnerability, the distribution of forest ownership and change in forest cover in Finland, Spain and Kenya. The last part is devoted to applied adaptation policies and national plans to climate change in the mentioned countries.
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Vyhodnocení fenologických fází dospělého bukového porostu na Ekosystémové stanici Štítná nad Vláří
Střecha, Jaroslav
At the Štítná nad Vláří Ecosystem station in the White Carpathians, phenology cameras have been taking pictures inside an adult beech forest from a meteorological mast, together with the collection of meteorological data since 1960. Phenology records regularly recurring changes in plants, the so-called phenophases, in relation to the external environment and especially the weather. Therefore, forest ecosystems function as an important bioindicator of climate change. From the phenologial observation in 2018–2020, beech phenophases were evaluated in two ways. Visual evaluation and analysis of the vegetation index from the phenology camera image. Image analyses record the phenological stage earlier than the observer. There was an increase in the average annual temperature, resulting in a longer growing season. The growing season was extended by up to 82 days. This trend of climate change, together with the occurrence of years with a lack of precipitation, will have a negative effect on the vitality of beech and forest ecosystems.
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Optimalizace využívání krajiny na farmě rodiny Šťastných ve Svatoslavi
Hudec, Vít
People have been working the land since time immemorial, and it is no different in the area of interest. The family farm specialises in rearing cattle for meat on its land. Forests, pastures, watercourses, woodlands, all this can be found on their farm. It is located in the Vysočina region northwest of Třebíč. In recent years the land has undergone significant changes, the woody vegetation is dying, and the pastures are suffering from drought. The area characterisation of the area of interest has shown that the soils and weathered subsoil on the slopes have a high infiltration rate, while the valleys with low infiltration capacity have been drained in the last century. There have also been changes in climatic conditions, with a 1,1 °C increase in average annual temperature over the last 10 years, a 25 mm decrease in annual rainfall and a change in rainfall distribution. Based on a synthesis of all the information about the area, the paper proposes a set of measures to help the landscape respond flexibly to climate change. The result is an inventory of catalogue sheets relating to each element in the landscape, which will guide farm owners in their management.
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Návrh naučné a turistické stezky na ostrově Sokotra
Kaplánek, Tomáš
The thesis focuses on designing an educational trail and tourist routes on the island of Socotra. The educational trail is located in the forest of dragon's blood trees (Dracaena cinnabari) on the Firmihin plateau. The route is approximately 6 km long with an elevation gain of 300 m. Ten information boards have been designed to describe the dragon's blood trees and the environmental issues affecting this area. The information provided includes issues such as land degradation, erosion, climate change and its impacts, inhibition of natural tree regeneration, and how local people influence this ecosystem. The same topics are also described in a 24-page brochure created in both Czech and English. Additionally, four tourist routes have been proposed in the work, which are color-coded, with three located in the Haggeher Mountains and one in the Homhil area. Information on the educational trail and tourist routes is also provided through the ArcGIS StoryMaps web platform.
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Vliv světla na fotosyntézu bylin v podrostu doubrav
Zvyniatskovskyi, Yan
The forest environment is increasingly changing. Climate change brings along not only changed macroclimate. Stand microclimate is changing as well due to changes in tree species composition and the natural reduction in tree cover because of increased mortality. Understory herbs are sensitive to changes in the tree canopy cover. In sparse stands, more light reaches the understory compared to dense stands. Different understory herb species have different ability to use light and adapt to changing conditions. Short-term changes in their photosynthesis lead to long-term changes in species composition and their abundance. This bachelor thesis investigated the effect of different light availability on the photosynthetic parameters of understory herbs. I compared 8 taxa from four groups of Ellenberg ecological indicator values (EIV). The research was carried out in a stand of thermophilous oak-hornbeam in the Pálava Protected Landscape Area (PLA), on plots with different levels of tree canopy thinning. Herbs growing under fully stemmed stands plastically reduced respiration compared to herbs in the thinned forest, which allowed them to survive even under dense forest cover. However, they were still able to achieve high rates of photosynthesis under full illumination for short periods of time, i.e., they actively utilized short episodes of direct sunlight. Species characterized by EIH as shade-loving respired less in the dark than species with higher EIH in relation to light, suggesting a link between light availability and long-term abundance of herbaceous taxa. The results of this study suggest how the herbaceous understory of temperate forests might change in the context of climate change, with potential implications for forest typology.
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Hunting and fishing in the light of selected environmental issues
Rudolf, Vít ; Stejskal, Vojtěch (advisor) ; Sobotka, Michal (referee)
1 Hunting and fishing in the light of selected environmental issues Abstract The diploma thesis focuses on the hunting and fishing in the light of selected environmental issues. Both hunting and fishing are activities that may serve as freetime activities, but their main purpose is nature conservation and as such should respond to the changes in nature brought about by climate change. The aim of this diploma thesis is to provide the reader with a basic insight into the legal regulation of hunting and fishing and to assess the current legal regulation in terms of preparedness for the changes in nature brought about by ongoing climate change. The second objective is pursued by answering three questions: "Does the Czech legislation sufficiently care about biodiversity conservation?", "Does the Czech legislation effectively combat invasive and non-native species?" and "Is Czech legislation prepared for the changes in animal behaviour that will inevitably occur in the context of climate change?". The diploma thesis is divided into five chapters. The beginning of the diploma thesis focuses on the issue of climate change, where the emphasis is mainly placed on laying out the problems related to the loss of biodiversity, the introduction of non-native species and changes in animal behaviour. Next, the diploma...
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How climate change affects biotopes protected under Natura 2000 in southern Bohemia?
Vaškovský, Adam ; Křenová, Zdeňka (advisor) ; Trnka, Miroslav (referee)
Warnings of the intensity and widespread negative impacts of ongoing climate change are becoming more urgent. EU countries have created a unique network Natura 2000 to protect Europe's biodiversity and are legally obliged to protect the sites so that their conservation targets do not deteriorate. The key question is whether the static Natura 2000 system will continue to fulfil its purpose in the future, or whether climate change will lead to significant losses of European biodiversity. To date, there are still very few studies that address the modelling of climate change impacts on Natura 2000 sites. In this paper, using a new method combining climate envelope models with procedures applied to assess climate change risks to agroecosystems, I assessed the impact of climate change on eight selected natural habitat types (NHTs) occurring in south Bohemia. Agroclimatological indicators generated by the AgriClim model were used as predictors of the occurrence of suitable climate for NHTs. For modelling, I used three machine learning algorithms (generalized additive model, artificial neural network and random forest) and two ensemble learning techniques (averaging and stacking), of which I chose random forest as the most suitable for the resulting predictions. The modelling results show that for the...
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International Organisation for Migration and African Union and their actions towards sustainable development in East Africa
Králová, Helena ; Tesař, Jakub (advisor) ; Kučerová, Irah (referee)
This thesis focuses on the African Union (AU) and the International Organisation for Migration (IOM), analysing their respective roles in implementing sustainable development in East Africa from 2015 to 2020. The essential research questions investigate how international organisations influence the process of socialisation and the acceptance of norms related to climate change, migration, and sustainable development. Furthermore, this research uses concepts of social constructivism, such as the norm cycle and socialisation, and outlines the two organisations approaches to regional actors in East Africa. In this qualitative analysis, a case-study approach is adopted to help understand how different international organisations promote norms related to the same topics in the same region. To conduct the investigation, documents published by both international organisations are examined using critical discourse analysis. The results showed that the International Organisation for Migration draws attention to the positive contribution of migration to sustainable development and the living conditions of migrants. IOM focuses on a multi-stakeholder approach in its strategy. The study suggests that the African Union emphasises the role of states perceived as the main driving force and focuses on the local...
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