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Environmental determinants of bird species richness and population densities in sub-Saharan Africa
Dubský, Marek ; Sedláček, Ondřej (advisor) ; Reif, Jiří (referee)
The research of factors influencing bird's species diversity and abundance will allow us to manage the landscape in the way to create suitable conditions for survival of species. For the purposes of this work, I divided bird assemblages into 3 groups on local level: forest birds, shrubland birds and grassland birds. The forest bird species were most influenced by height of canopy, its compactness and fragmentation of the forests. The size of the fragment, fragment matrix, isolation of the fragment and birds sensitivity to edge effect were deciding factors of number of species and individuals in each fragment. The shrubland birds were most influenced by vegetation structure in meaning of presence of shrubs, trees and grassland. They were also influenced by vegetation species composition, frequency and form of disturbances (fire, grazing), they reacted positively to transformation of landscape into agroecosystems and they reacted negatively to shrub encroachement. Grassland birds reacted to various height of grass, they reacted negatively to presence of trees and shrubs and also to disturbances caused by human. It is the least studied group of birds in Africa. As fot the elevation gradient, the lowland assemblages of birds changed to mountains assemblages at attitude of about 1250 above the sea...
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Effect of synurbanization on bird populations
Zeman, Vít ; Lučan, Radek (advisor) ; Šálek, Martin (referee)
Currently we can observe the expansion of human environment to the countryside all around the world. As the needs of man for space grow, so do the cities and urban environments expand. Ever more types of organisms are adapting to this environment, which allows us to record the changes that appear, either on the population or on the individual level. This Bachelor thesis is trying to summarize the existing knowledge of the effect of urbanization, and related synurbanization, on popualtions of birds, in the form of a literary research. This being an extensive topic, the thesis is focused on specific details, concerning primarily differences in population density, nesting success, condition of the birds, and predation pressure in urban and natural communities. Powered by TCPDF (www.tcpdf.org)
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Abundance-distribution relationship: the importance of ecological specialization
Farkač, Jan ; Hořák, David (advisor) ; Reif, Jiří (referee)
6 Abstract The relationship between local abundance and regional distribution is a widespread ecological pattern. It is frequently reported to be positive, however exceptions have been evidenced. But the explanation is not clear at all. There are many of mechanisms explaining this relationship, from those related to statistical issues, those explaining it by metapopulation dynamics, to rates of ecological specialization, which are the most frequently considered. But it is likely that certain mechanisms work together. One of the principal hypotheses is the resource breadth hypothesis, which claims that generalists tend to be more abundant and widespread whereas specialists occur in small range and less abundant. There are two ecological relationships linked to ecological specialization. It is a niche breadth-range size relationship and niche breadth-abundance relationship. While the former is well documented, the information about latter is rather scarce. This thesis sums up existing studies about distribution-abundance relationship with a special focus on importance of ecological specialization. Key words: geographical distribution, local density, niche breadth, ecological specialization
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Density dependent growth of brown trout Salmo trutta in oligotrophic streams
Závorka, Libor ; Slavík, Ondřej (advisor) ; Frouzová, Jaroslava (referee)
This thesis deals with the influence of population density on the growth of brown trout Salmo trutta. The research was carried out in the Šumava National Park in the river basins of two oligotrophic streams, the Vydra and the Křemelná. Data has been collected between years 2005 and 2010, every spring and autumn. Fish were caught via electrofishing and the length and weight of each individual were measured. Every individual caught was marked in a unique way. A few samples of scales were taken from some of them. The scales were fixed into laboratory slides, scanned and measured by graphic software. According to the differences between annual lamellas density, the age and the annual growth of individual's body length were estimated. Thanks to these results a negative relationship between the individuals' of age 1+ growth rate and the population density was confirmed. The importance of this thesis is mainly in comparing the influence of different spatial and time definitions of population on this relationship. The influence of the population density in spring (the initial time of the growth period) was proved to be essential for the growth rate. This fact suggests the importance of compensation growth intensity after the long period of winter for individual's general growth under conditions provided by...
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The report on the asp and spined loach populations’ status in SCI – valley reservoirs.
Blabolil, Petr ; Šmejkal, Marek ; Bartoň, Daniel ; Baran, Roman ; Draštík, Vladislav ; Jůza, Tomáš ; Kočvara, Luboš ; Koliada, Ievgen ; Kolařík, T. ; Matějíčková, Ivana ; Prachař, Zdeněk ; Sajdlová, Zuzana ; Soukalová, Kateřina ; Vebrová, Lucie ; Vejřík, Lukáš ; Kubečka, Jan
The aim of the ichthyological survey was to assess the status of reproductively active population of asp (Leuciscus aspius) in the SCI (site of community importance) Želivka (Švihov Reservoir) and spined loach (Cobitis elongatoides) in the SCI Nová Říše (Nová Říše Reservoir).
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Definition of rural areas: approaches, methods and application to the territory of South Bohemia
NOVÁKOVÁ, Eva
The presented bachelor thesis deals with defining of urban and rural landscape areas. The main aim of the thesis is the application of three different methods of defining countryside residencies in the territory of South Bohemia from the perspective of the population size of municipalities, population density and commuting principle and also synthesis of the aforementioned approaches. The practical part is preceded by three chapters describing the theoretical foundations of the issue of rural landscape defining and providing South Bohemia characteristics. The final two chapters are focused on methodology, data processing and results analysis.
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Influence of population density at the provision of public services: municipal waste management
Kuhnová, Hana ; Vejchodská, Eliška (advisor) ; Vojáček, Ondřej (referee)
Collection of waste is one of the most important public services provided by municipalities. This expenditure has a significant impact on the budget of the municipality and therefore it is important to know the factors that affect it. In addition to other factors, there can exist a phenomenon called suburbanization. This phenomenon of recent years, the city has been extended in width, which is followed by a reduction in population density. Carruthers and Úlfarsson (2008) in his work write that for many public services, the cost per unit, ie per person or household, higher output at low population density, because here you can not take advantage of economies of scale that are achievable, if users are concentrated in one place. This work seeks to examine whether this hypothesis is true for czech villages. On data from hundred municipalities in the Czech Republic for the year 2011 were able to demonstrate that if population density rises by 1 %, expenditure on collection of municipal waste will decrease by 10,41 CZK per capita.
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The development and demographic consequences of suburbanization in the base of Prague
Postlerová, Marika ; Pechholdová, Markéta (advisor) ; Nývlt, Ondřej (referee)
This bachelor work shows the characteristic progress of suburbanization in the base capital city of the Czech Republic, after the Velvet Revolution. The Second World War interrupted the very successful dynamic era of Czechoslovakia and the following socialistic era had been holding the natural pressure on suburbanization, till the fall of the communist regime at 1989. After the transformation of 1989, it appeared that all those years of struggling; still the Czechs desire to live in a family house in the countryside also known as the suburb. Finally, it was possible to have a restful life in the countryside with job opportunities a short distance nearby capital city. The analyst is using the suburbanization calculations in Central Bohemia Region, depending upon the capital city, using exponential function for the period 2001-2011, which shows the general estimation of suburbanization process in the certain area and also refers to the possible reasons for the differences which are diverged from the general trends. The analyst results may also help to explain future impacts for certain areas. At the end of this work, the main goals have been set up for the regional politics, which is trying to help every region to stay independent and also increase their cooperation and solidarity.
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