National Repository of Grey Literature 418 records found  beginprevious268 - 277nextend  jump to record: Search took 0.01 seconds. 
HAS THE CLIMATE CHANGE IN CENTRAL EUROPE BEEN ACCELERATING OR DECELERATING?
Maryško, Kryštof ; Huth, Radan (advisor) ; Pokorná, Lucie (referee)
6 Abstract The thesis deals with detailed analysis of the climate change rate throughout the European continent with an emphasis on Central Europe in the period 1951-2005. The main aim was to find out whether the rate of climate change is getting lower or higher during the monitored period and identify when the changes in the rate occurred. Changes of three climatic elements - minimum air temperature, maximum air temperature, and precipitation, were described for climatic seasons of the year. Other climatic elements were also available, however, amount of data is insufficient for such a detailed trend analysis for the entire second half of the 20th century. First part of the thesis summarizes current knowledge of changes in climate change rate, which is so far rather scarce. Most scientific articles are limited to detecting warming or cooling, decrease or increase in precipitation during a certain period. They, however, do not research when these changes of climatic elements occurred. For my analysis, which tries to offer a detailed insight into changes in European climate, daily records from European Climate Assessment and Dataset (ECA&D) database of 122 stations (spaced as evenly as possible) were used. For examining variability trends (i.e. the rate of climate change) I tested moving 20-year trend (15-...
Influence of fish pond management, land use in catchment and climate change on species composition of blue-green algae blooms
Kroupová, Kristýna ; Stuchlík, Evžen (advisor) ; Pivokonský, Martin (referee)
The aim of the thesis was to explain expansion of cyanobacterial blooms and the change of their species composition in surface standing waters during the last 2-3 decades as a result of fishery management, land use in catchments, and climate change. Cyanobacteria possess a range of unique and highly-adaptable eco-physiological traits, which enable them a mass occurrence and a dominance over the other phytoplankton groups under recent anthropogenic changes (nutrient loading and rising temperatures). Moreover, many species of cyanobacteria produce cyanotoxins, which increase their resistence against zooplankton grazing and cause severe deterioration of the water quality. In consequence of changes in fishery management (a decrease in the use of superphosphate as a fertilizer during the year 1970), the fish stock density increased and the clear water phase disappeared. This is responsible for a change in species composition of cyanobacterial water blooms. Summer blooms of Aphanizomenon flos-aquae were replaced with A. flos-aquae var. klebahnii. The current composition of water blooms in ponds differs considerably from the typical composition in the 1990s. For example, recent expansion of Woronichiniana naegeliana is caused by the higher stock densities and the shift from a two-year cycle of fishery management...
Economic Rationale for Damage Functions Entering the Social Cost of Carbon
Hochmann, Lukáš ; Havránek, Tomáš (advisor) ; Rečka, Lukáš (referee)
Climate change studies repeatedly report the present value damage from global warming in the realms of trillion USD. To adopt an efficient climate policy, precise estimates of the costs and damages are essential. This thesis aims to review the most influential social cost of carbon models and to propose for the first time a best practice approach to constructing the damage function. Based on the reliability of the key estimates, two alternative approaches are proposed. The first consists of deriving a highly universal damage function and conse- quent calibration by multiple point estimates. The latter is based on damage disaggregation to different sectors and subsequent single-point calibration of each contribution separately. Both approaches address the current challenges for the damage function - a flexible functional form and treatment of intangible damages. JEL Classification D62, D90, Q51, Q54 Keywords Social cost of carbon, SCC, damage function 1
Publication Bias in Measuring Anthropogenic Climate Change
Rečková, Dominika ; Havránek, Tomáš (advisor) ; Zeynalov, Ayaz (referee)
People around the world are interested in climate changes. Especially the impact of human being on climate changes plays an important role in the policy discussion about environment. One of the measures of anthropogenic climate change is climate sensitivity. The main aim of this thesis is to apply meta-analysis methodology on relationship between human activity and climate change. Until now, tens to hundreds of studies have been written on this topic, but only few report the estimate of climate sensitivity. Despite majority of the studies refer to recognizable influence of human activity on the climate change, the results of individual studies do not correspond in absolute values perfectly. Until now only one meta-analysis concerns publication bias in literature covering climate change, it uses vote- counting and detects publication selectivity efforts. But no meta-regression analysis was published on this topic yet. The thesis investigates if the results of studies reporting climate sensitivity are influenced with the effort to publish only positive and significant estimates. It applies effective statistic instrument, meta- regression analysis, that allows systematic evaluation of an inconsistent sample of estimates. This method was applied on the data set consisting of 48 estimates coming from 16 studies....
Success Factors and Barriers for Climate Protection Projects in the Selected Czech Cities
Hejralová, Eva ; Rynda, Ivan (advisor) ; Sutlovičová, Klára (referee)
Cities are important actors in global climate protection. Almost 80% of global CO2 emissions are produced in urban areas. At the same time cities are in a good position to bring out innovative solutions. Local initiatives in the Czech Republic often take an implicit form: they don't aim directly at reducing greenhouse gas emissions. This paper analyses nine projects in the building sector, which have been implemented by Czech cities. It looks for factors that have contributed to the initiation of studied projects and facilitated or inhibited its implementation. Factors have been gathered throughout semi-structured interviews. The research have revealed two relevant barriers and twelve success factors, which have been classified according to the thematic categories: "Economics," "Livability," "Politics," "Institutions," and "Information." Most of them concern the category "Information," while none of them concerns the category "Livability." The research outcomes can serve as an inspiration for other cities and also for actors shaping conditions for local climate protection, in particular NGOs and central government.
Carbon allocation in evergreen and decidious temperate tree species under the elevated concentration CO2 and O3
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Konrádová, Hana (referee)
An ongoing increase in atmospheric CO2 concentrations and tropospheric O3 is expected in coming years. These changes are mostly caused by anthropogenic activities and influence remarkably not only plants but the climate on the Earth. Physiological processes in plants determining carbon assimilation and allocation in plant organs are changing in a consequence of variations of these gases in the environment. Tree species represent importatnt C pools and changes in C allocation may effect their sink capability in the global C cycle.Increased CO2 concentration in the atmosphere often leeds to incereased rate of photosynthesis lowered photorespiration what in turn may lead to enhanced C storage in plant biomass. The C storage into sinks is mediated through the assimilation organs, which are disturbed by O3. Ozone is toxic to plants and trees are due to their longevity exposed to ozone influence repeatedly for long term. The response to increased CO2 and O3 concentrations, is the most commonly investigated on two typical representatives of European temperate species: deciduous European beech (Fagus sylvatica L.) and coniferous Norway spruce (Picea abies L. Karst.) The aim of the present review was to summarize the knowledge about the effects of increased concentrations of CO2 and O3 acting separately or in...
The impacts of climate change on environmental geopolitics of the Arctic
Pelletier, Mireille ; Landovský, Jakub (advisor) ; Romancov, Michael (referee)
The new fact that the environment is becoming the main factor of geopolitical transformations in the Arctic region has been triggered mainly by climate change. In the North, this recent aspect of geopolitics, in correlation with the environment, leads sometimes to tensions between countries, but also to a need for cooperation. The question brought by such conditions is, to which extent will this climate change provoke cooperation or conflicts between the Arctic states. The purpose of addressing the problem is to understand what kind of challenges would be facing the international relations between circumpolar countries and how the environment is playing a geopolitical role in them. The objective of the main research question is to assess the importance of climate change over the geopolitics of the Arctic through several spheres of geopolitics: environment and bio-diversity, economic activity of the region, sovereignty and territoriality, security of the circumpolar states, and international and diplomatic relations. The trans-border and transnational nature of environmental issues is another important factor, since nature does not respect human-made boundaries and an environmental concern, such as climate change and its aftermaths, cannot be exclusive to a state along the lines of its borders.
Palaeocology of plant-arthropod associations from the Lower Miocene of the Most Basin in northern Bohemia (Czech Republic)
Knor, Stanislav
Terrestrial plants and insects account for the majority of the Earth's biodiversity today, and almost half of all insect species are herbivores. Thus, insects and plants share ancient associations date back for more than 400 million years. However, investigation of their interactions stands largely at the beginning in Western Europe. Nearly 4300 plant remains showing various kinds of feeding damages are available for the present study. These trace fossils are classified as so-called functional feeding-groups supply an outstanding example of the complexity, the structure and the changes of terrestrial ecosystems, are not well known during this interval. In Europe, the Neogene is characterized by palaeogeographic re- organization due to the collision of the African with the Eurasian plates. The Neogene plant record in Europe is rich and diverse offering a profound large-scale understanding of the floristic and vegetational development. A database of fossil traces from the Most Basin was compiled and analyzed by various statistical methods in terms of the diversity and intensity of palaeo-herbivory. The primary objective is to present results on the development of insect herbivory through the section of the Bílina Mine in North Bohemia, with the aim of understanding principal factors that caused the...
Assessment of climate change impacts on selected ecosystem services in the Czech Republic: application of land use scenarios
Lorencová, Eliška ; Vačkářová, Davina Elena (advisor) ; Müller, Karel (referee) ; Cudlín, Pavel (referee)
Doctoral thesis abstract Assessment of climate change impacts on selected ecosystem services in the Czech Republic: Application of land use scenarios MSc Eliška Lorencová Climate and land use change are recognized as the greatest global environmental problems. Both considerably impact delivery of crucial ecosystem services, such as carbon sequestration, water flow regulation, erosion control, and food and fibre production. By combining future projections of ALARM scenarios (for years 2020, 2050 and 2080) with modelling of ecosystem services, the study aims to evaluate climate change impact on selected ecosystem services (carbon storage and sequestration, erosion control and sediment retention) in the Czech Republic. This study provides quantitative as well as spatially explicit analysis of the impacts on selected ecosystem services in the Czech Republic. Performed ecosystem service assessment indicates that spatial distribution of provision of ecosystem services, such as carbon storage and sequestration, sediment retention reflects the projected future land use changes. In case of carbon sequestration, SEDG scenario shows the lowest carbon sequestration rates accounting for 37,029.6 Gg C within the period 2000-2080. Stable vegetation cover is one of the factors that play important role in amount of sediment...
Závislost predace a rychlosti metabolismu na teplotě z pohledu kořisti i predátora
MODRÁ, Denisa
Climate changes affect species interactions which can have cascading effect up to the ecosystem level. This work investigates the effects of temperature and predator size on predator prey interactions by measuring the feeding rates of predators and metabolic rates of both predator and prey, using dragonfly larvae Aeshna cyanea and toad tadpoles Bufo bufo as a model system. Possible consequences of the findings for the impacts of climate change and predation on amphibian populations are discussed.

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