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Changes of diversity and abundance of aquatic avifauna in relation to the physical-geographical environment
Adam, Matyáš ; Romportl, Dušan (advisor) ; Chuman, Tomáš (referee)
Changes of diversity and abundance of aquatic avifauna in relation to the physical-geographical environment ABSTRACT. This thesis looked into the issue of impact of changes of suitable habitat structure and climatic conditions, as the most discussed environmental factors, on model group of organisms - waterbirds. In the first part there was characterized effect of these factors on model group by the available literature. The relevant environmental variables were processed in the second part. For analysis of impact of these environmental factors on abundance and diversity of aquatic avifauna there were used data from International Waterbird Census in January term from 93 sites throughout the Czech Republic. Data were chosen for the period 1975, 1990 and 2006, in accordance with the database CORINE Land Cover. As multivariate data analysis there were used redundancy analysis (RDA) and mixed models with random effects, which showed significant associations with both weather conditions and other environmental factors. Selected environmental variables contributed substantially to the explanation of variability in species data, that was also tested suitability of their use. Keywords: physical-geographical environment, climate change, land cover, habitat structure, biodivesity, waterbirds
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Forest soil acidification in the Czech Republic and analysis of differences between spruce and beech stands
Růžek, Michal ; Chuman, Tomáš (advisor) ; Romportl, Dušan (referee)
Forest soil acidification in the Czech republic and analysis of differences between spruce and beech stands Abstract Acidification of forest soils is the process which considerably affected soil chemistry in the 2nd half of the last century. The aim of this paper is to give comprehensive review about the soil acidification, especially with focus on differences between forest species Norway spruce (Picea abies) and beech (Fagus sylvatica). The work also provides information about acidification mechanisms and its historical development in the Czech Republic. In the practical part the soil conditions under the beech and spruce stands from 5 mountainous and upland sites are compared. The results showed better soil conditions under the beech stands, where higher pH values and concentrations of base cations were measured. However there were observed lower concentrations of toxic Al3+ in deeper horizons under the spruce stands, although the difference was insignificant. key words: soil acidification, spruce stands, beech stands, Czech Republic
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Effect of environmental variables on diversity and abundance of water bird species
Adam, Matyáš ; Romportl, Dušan (advisor) ; Chuman, Tomáš (referee)
Effect of environmental variables on diversity and abundance of water bird species Abstract The environmental variables affect the abundance of species and individuals of most living organisms significantly. The intensity of environmental changes can be evaluated by using bioindicators. The birds rank among them. The most significant variables of the wide range of abiotic, biotic and anthropogenic factors are likely change of habitat structure and quality and climatic changes. In this thesis there is addressed issue of the impact of these factors in the model group of organisms - water birds. The first part is devoted to the characteristics of the impact of environmental variables on the abundance and species diversity of birds by the research of available literature. The relevant data are processed in the second part. There is carried out basic analysis of major environmental factors affecting the diversity and abundance of waterfowls at locations of interest. Keywords: environmental variables, climate change, land cover, habitat structure, biodivesity, waterfowls
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Assesment of land use influence on landscape naturalness
Kaňková, Helena ; Romportl, Dušan (advisor) ; Matějček, Tomáš (referee)
1 Assesment of land use influence on landscape naturalness Abstract Human activities are putting an increasing pressure on natural areas. Complex understanding and evaluation of human impact on the environment is considered to be a key tool to preserve natural balance. Biodiversity was chosen as proxy for naturalness as it has been recognized as one of the main components of environmental stability. Several different indices has been developed to assess human-induced changes in biodiversity. In this study, mean abundance of original species relative to their abundance in undisturbed ecosystems (MSA) is used as an indicator for current state of naturalness. Indicator MSA is built on simple cause-effect relationships between environmental drivers and biodiversity impacts, based on state-of-the-art knowledge. Drivers considered are landcover change, land-use intensity, fragmentation and infrastructure development. As most of biodiversity indices, MSA illustrate prevailingly poor condition of nature as a result of human induced pressures, especially land cover change. Considering constantly increasing population and economic development human pressure grow is likely to continue during the coming decades with irreversible loss in the diversity of life on the Earth. Keywords: Mean species abundance (MSA) - land...
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Landscape changes due to suburbanization - an example of south-eastern outskirts of Prague
Paločková, Anežka ; Romportl, Dušan (advisor) ; Chuman, Tomáš (referee)
The study deals with the evaluation of landscape changes and ecosystem functions in the case study situated in the hintreland of Prague with the emphasis on the process of suburbanization. It analyzes the amounts, the range and the types of the changes of landscape due to suburbanization process and their effects on landscape structure and function. Landscape changes are evaluated using remote sensing and software ArcGIS, function and services of ecosystems are evaluated by modified Hessen method. Powered by TCPDF (www.tcpdf.org)
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The impact of urban sprawl on the environment.
Havel, Petr ; Chuman, Tomáš (advisor) ; Romportl, Dušan (referee)
The suburbanization process - a shift of population and activities from city centre to its fringe - is not only a socioeconomical phenomenon; city spatial expansion is a serious concern for an environment as well. The volume of suburban and sprawling areas is constantly increasing, moreover the character of this development is inefficient both spatially and energetically. A crucial changes take place in a landscape, which is being fragmented and homogenized. Those changes affect organisms, which live in the landscape; their natural environment is intensively modified and not all of them are able to get used to a newly created conditions and resist to a pressure of invasive species. A lot of compacted and impervious surfaces negatively influence not only the biota, but also a water quality, infiltration and water regime. Last but not least, new development seals a lot of quality agricultural land. Sealed soils are irreversibly deteriorated and become useless for further agricultural use. Despite the fact, that legislative in the Czech Republic should protect the high-quality agricultural soils, the study, made in the surroundings of D1 highway shows that's not the case. Two thirds of the commercial suburban development take place on the most productive and valuable soils. This number suggests poor...
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Defining national geoparks in the Czech Republic - evaluation from the perspective of geodiversity
Masopustová, Lenka ; Romportl, Dušan (advisor) ; Treml, Václav (referee)
This thesis summarizes the basic knowledge about Geoparks with a focus on the situation in the Czech Republic. The study shows their position in nature and landscape conservation and describes Czech Geoparks on the basis of selected natural characteristics. It further includes comparative analysis of criteria for obtaining the title National Geopark, respectively European Geopark. The practical part deals with approaches and methods of evaluation of geodiversity in the Czech Republic regarding the distribution of current and planned Geoparks. Based on the results of the analysis it suggests another areas suitable for definition. The study provides a comprehensive geodiversity index based on the sum of standardized values of Shannon's diversity index (SHDI) that had been calculated separately for each data bases.
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Alpine treelines in the High Asia and their relation to temperatures
Yakubouskaya, Alina ; Treml, Václav (advisor) ; Romportl, Dušan (referee)
Treeline is a gradual transition from closed forest to treeless areas at a certain elevation above the sea. According to its forms, we distinguish diffuse, abrupt, island treelines and krummholz. Depending on the form we can assume the main factors affecting its occurrence and possible response to climatical changes. Generally, the position of the treeline in various latitudes relates to the thermal characteristics, mainly to the temperatures of the growing season, limiting tree growth, the availability of necessary nutrients and seedling survival. Limitation by an insufficient carbon balance as a cause of the ecotone, is not considered as a major or decisive factor by many authors. In most cases they proved a sufficient carbon balance at the treelines and fixed an incresing amount of non-structural carbohydrates, needed for trees to activate their growth after a period of dormancy. This work was focused primarily on identifying the positions of the treeline in the mountains of High Asia, and determining the basic thermal characteristics relating to these sites. The best indicator, connected to the position of the treeline in this region was founded. The results were compared with global research. Key words: treeline; diffuse, abrupt and island treelines, krummholz, sink limitation hypothesis,...
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Distinct eco-phenomena in Central Europe
Majerová, Martina ; Treml, Václav (advisor) ; Romportl, Dušan (referee)
The subject of essay is eco-phenomena and its influence on landscape diversity. The essay contains definitions of particular eco-phenomena types and attributes elaboration focused on extraordinariness of this effect. Each eco-phenomena type is described, his uniqueness is illustrated on examples of local vegetation types and eco-phenomena description is completed by concrete locations with this sort of effect. Next part of the essay contains information about distribution particular eco- phenomena locations on the Czech Republic territory. There are information about description mentioned locations and sorting according to bio geographic classification of the Czech Republic. There is map included. Key words: eco-phenomena, phenomena, biodiversity, geodiversity, landscape
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Landscape typology in the area of the Bohemian Paradise
Merhautová, Zuzana ; Lipský, Zdeněk (advisor) ; Romportl, Dušan (referee)
Landscape typology deals with the classification and description of cultural and natural landscape. European landscapes are going through irreversible changes that are mainly caused by intensive agriculture as well as they are affected by phenomenas such as globalization and unification. The traditional structure of the European landscape is disappearing. Landscape typology can serve us as a base for monitoring of these changes. There are many different methods of how to classify the landscape, which is a complicated object of interest. This thesis presents the landscape typology in the area of Bohemian Paradise using the objective statistical method of cluster analysis. Cluster analysis is a set of tools for building groups (clusters) from multivariate data objects. The aim is to construct groups with homogeneous properties - landscape types. To classify the landscape of Bohemian Paradise, only quantifiable data in digital format were used. Land Cover, relief, moisture and soils were included in input layers. The classification was made in Twinspan - a software using the ordination method to classify the landscape in the divisive hierarchy. The typology of the area of Bohemian Paradise was divided into four hierarchical levels and at the last fourth level 16 types of landscape were identified. The results...
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