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Land-cover changes and climatic settings of the Úpské rašeliniště mire
Hejda, Tomáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
Mires, or wetlands, are very important habitats, ecosystems, as well as relict and recent reserves. The object of the study of mires is focused on morphological, hydrological and chemical characteristics as they are more discussed globally due to climate change. The present thesis deals with the characteristics of mires on a global scale, which are used in literature and make up their classification. The classification of mires is also addressed on the Czech scale with a focus on the Western High Sudetes. Mires of the Giant Mts. were analyzed according to climate conditions with a focus on the dynamics of land cover areas of Úpské rašeliniště mire and subsequently compared with Scandinavian mires. A particularly strong dependence on the Aapa type can be stated from the analysis. The vegetation above the alpine timberline primarily consisting of dwarf pines (Pinus mugo) and spruce families showed a substantial increase with respect to the impacts of climate fluctuations in the recorded period in Eastern High Giant Mts. Key words: mires, classification, Giant Mts., climate, vegetation change
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Recent shifts of alpine treeline ecotone in temperate and boreal part of Northern Hemisphere
Kolařík, Petr ; Treml, Václav (advisor) ; Romportl, Dušan (referee)
Treeline advance is often cited as one of the effects of the global climate change, especially the rise of mean temperatures. However, treeline dynamics is a complex issue. This thesis aims to describe factors that determine the position and dynamics of the alpine treeline and create an overview of treeline dynamics in the temperate and boreal parts of the Northern Hemisphere outside of Europe. A further goal is to create a database of treeline advance at locations in this region and then analyze this database. Of the 20 studied locations, 65 % showed treeline advance while treeline receded at only two locations. The highest rate of advance was recorded in the Rocky Mountains of North Americe, up to 1.59 m/yr. The highest rate of recession was recorded in the San Francisco Peaks, also in North America, where a recession of 1.21 m/yr was recorded. A statistical analysys showed no significant correlation between temperature trends and treeline advance. Locations that had undrgone a change in land use showed both the highest rate of advance and recession. It appears that anthrpogenic activity is an importnant factor influencing the dynamics of alpine treelines.
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The buildable areas in the physical plan of Klatovy during the period 1994-2014
Vacková, Marie ; Perlín, Radim (advisor) ; Treml, Václav (referee)
The thesis is focused on buildable areas of the town of Klatovy which represent main trends of potencial urban development in the district. The first aim of the thesis is to analyze the development of buildable zone of the town of Klatovy from 1994 to 2014. The second aim is to find out causes why another buildable areas were established in the physical plan of Klatovy in the period 1994-2014. To achieve these aims, firstly, an analysis of buildable areas was performed to evaluate a process of establishment and a process of using town buildable areas. Secondly, directed interviews were conducted with representatives of public administration as key persons of physical planning. The results of the thesis show that there was an excessive amount of established buildable areas which weren't utilized to a large extent. The main reasons for establishing new buildable areas during the assessed period related to the requirements of landowners and to an open attitude of town representatives to their approval. Keywords: physical planning, physical plan, buildable area, town
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Dendroclimatology of arctic shrubs
Lexa, Martin ; Treml, Václav (advisor) ; Vejpustková, Monika (referee)
Thesis focuses on the influence of climate on microscopic structure of anatomic features in juniper wood. Dendrochronology as a method reaches its limits in the Arctic regions. Insufficient network of meteorological stations providing sufficiently long series of climatical data is the reason of increasing interest in studying Arctic shrubs, which can occur even beyond the latitudal forrest line. Thirty-three discs from juniper shrubs were collected in Gangasdalen valley on the banks of Jarfjord fjord in the August 2014. The master chronology was developed from 26 cross-dated samples. Eight carefully chosen samples were used for microscopic measurement of wood anatomic features during the reliable period of the main chronology using WinCell Wood Cell Anatomy software. Lumen area, wall thickness, number of cells and tree ring (its part) width were measured for both whole ring, and for earlywod and latewood. It was found that ring width does not necessarily have the highest dependency on climate and therefore may not always be the best climatic proxy. The highest dependency reached the number of cells, which was generally positively correlated with summer temperatures. On the other hand, lumen area shows the lowest dependency on climate.
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Response of sedimentation and erosion rates to changing human pressure
Kašpar, Vít ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
While on the continental or global level and across the long time-scales, erosion and accumulation processes are largely governed by tectonics, terrain properties, geological settings and climate play a key role on the landscape or local levels and on short time scales. However, from the Neolithic onwards, human society has become an important factor affecting erosion-accumulation processes. As a result of agricultural activities, population expansion and land use changes soil has been washed downslope by soil erosion associated with formation of gullies. Furthermore, an increase of deposition rates was observed for colluvial, alluvial and lake deposits. The aim of this thesis is to review past soil erosion and accumulation processes connected with land use changes within the central Europe during the Holocene. 37 case studies documented generally strong relation between land use intensity and erosion and accumulation processes. First phase of anthropogenic accelerated erosion-accumulation processes was recorded in the late Eneolit period; however, the most remarkable acceleration of soil erosion occurred during landscape colonisation in the High Middle Ages. The second part of thesis aims at dating of two gullies in the Polomené hory Mts. Formation of gullies was studied using exposed roots. In...
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Treeline rise as a consuquence of increasing temperature and land-use change
Kolář, Václav ; Treml, Václav (advisor) ; Chuman, Tomáš (referee)
Treeline advance to greater altitude is observed in the majority of European mountains. Many authors have attributed treeline advance to increasing temperatue, others to decrasing anthropogenic influence. The aim of the thesis was to describe dynamics of treeline and influencing factors. Based on newly created database of case studies I asked, whether the treeline agnace is controlled by increasing temperature or by land-use change. My treeline database documented, that treeline advance in Europe ranged from -0,2 to 1,6 m.y-1 . Treeline was advancing most quickly in the Austrian Central Alps, conversely treeline in Ukraine Carpathians revealed retreat. Furthermore, it was found that treeline rise coincides with increasing winter temperatures. While the advance of northern treelines without human impacts is attributed to increasing temperatures and precipitation, remaining areas showed treeline advance in consequence of temperature increase and decreasing anthropogenic influence.
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Factors determining the alpine treeline
Oľhava, Rastislav ; Sklenář, Petr (advisor) ; Treml, Václav (referee)
The alpine treeline is a global phenomenon which represents sudden change between two significantly different vegetation types: mountain forest and low-stature alpine vegetation. The primary climatic factor that determines its position seems to be the temperature. We summarize the results that describe the relation between temperature and the altitudinal position of the treeline and search for a general formula that would determine its position. There are two hypotheses which try to explain what is the main limiting factor above tre- eline: C-limitation and growth-limitation. The first one claims trees are limited by carbon shortage, while the latter one favours low-temperature limitation of tissue formation al- though the carbon income is sufficient. This thesis provides a summary of the arguments for each of them and describes the state of knowledge on this matter.
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Klimatický signál v letokruhových chronologiích borovice kleče
Samusevich, Alina ; Treml, Václav (advisor) ; Vejpustková, Monika (referee)
Pinus mugo Turra (sensu lato) is a prostrate shrub growing above the alpine timberline in the mountain ranges of Southern, Central and Eastern Europe. It is well adapted to the harsh alpine environment creating different mechanisms for survival. The research was carried out in Krkonoše Mountains on base of Pinus mugo individuals compared with Picea abies trees. Samples from shrubs were gathered using serial sectioning from four sites in different elevations located on Sněžka Mountain and Smogornia Ridge. Further analysis of the sampled material was made with the help of different detrending methods to see which method will return the best growth response to climate parameters. RCS detrending and detrending via simple averaging reflected the best climate signal contained in dwarf pine chronologies. The advantage of these methods is based on their ability to reflect growth conditions of the particular site. Upper sites showed significant correlations with temperatures of the growing season, while on lower sites the signal was quite unclear. The amount of precipitation plays the significant role on shrub growth during the vegetation period (especially July month) and early spring when water is very important for growth initiation. Upper Pinus mugo sites showed high sensitivity to droughts, especially...
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Assessment of the impact of landscape structure on the dispersion of lynx in Posumavi
Sladová, Michaela ; Romportl, Dušan (advisor) ; Treml, Václav (referee)
Assessment of the impact of landscape structure on the dispersion of lynx in Posumavi Abstract: The big predators are a traditional group of bioindicative species, whose presence shows the state of environment and landscape within a region. As these animals recolonize the cultural landscape of central Europe it's needed to understand their space requirements and habitat preferences. The lynx (Lynx lynx) has been one of the Sumava forest species since the 70's. After almost 40 years the population of lynx has spread from Sumava and Bavarian Forest to forested parts of Cesky Les, Smrcina and Novohradske hory and to both sides of state borders. However today's state of lynx population, stable number of animals or genetic variability is endangered by many factors. Long term viability of the lynx population is - besides poaching or illegal hunting − affected by the loss of suitable habitats and ongoing fragmentation of the landscape. One of the possible solutions of negative impacts is delineation and protection of landscape permeability of habitat corridors. They might have provide supply of new individuals to small, extinction prone population and at the same time they could reinforce overall fitness population. This thesis has three main objectives:1) evaluation of landscape fragmentation and connectivity in...
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