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The importance of the forest continuity and fragmentation as a variable determining the diversity of beetles
Loskotová, Tereza ; Romportl, Dušan (advisor) ; Treml, Václav (referee)
Presented thesis examines the influence of two frequently discussed variables, forest continuity and forest fragmentation, on beetle diversity. An area of managed forests near Choceň was assessed. Longterm presence of local forest cover (minimum 240 years) can be documented by historical maps. Oak woodlands corresponding to the potencial vegetation were considered as continuous when older than 100 years. Those areas were compared with spruce forest. Fragmentation is understood to be a result of a conversion of species composition since 18th century until present. Other ecological and forest structural variables with possible influence on beetle populations were included. Out of the 38 completely described families of beetles were chosen into account. One defined taxonomically is represented by click-beetles (Elateridae) and the other group, saproxylic beetles, is defined by ecology. Their responses to variables of forest continuity and forest fragmentation were compared. Keywords: forest continuity, fragmentation, flight-intercept traps, biodiversity, saproxylic, beetles, Elateridae
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Spatial distribution and morphology of polygonal nets of frost and ice wedges pseudomorphs in the Czech Republic
Vohradský, Lukáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Ice and frost wedges are a geomorphological phenomenon which is directly related to periglacial environment and permafrost (Murton, 2007). The presence of permafrost in the territory of the Czech Republic in the Pleistocene period is directly proven by polygonal nets of ice and frost wedge pseudomorphs, which are clearly visible in some remote sensing images. Among others, they can also be used as indicators of paleoenvironmental conditions for the period in which their recent forms originated and developed and for the period of their secondary infilling (Sekyra, 1958). The present thesis focuses on the spatial distribution and morphology of polygonal nets of ice and frost wedge pseudomorphs which were created in the territory of the Czech Republic at the end of Pleistocene and the beginning of Holocene. The analysis of the spatial distribution of polygonal nets was carried out with freely available remote sensing images provided by the GoogleEarth Pro application (Google Inc., 2011). The number of locations with a potential presence of pseudomorphs was 629. Out of these, 49 were subjected to a morphometric analysis of polygonal nets and their corresponding landscape. Statistical data analysis showed that the described polygonal nets of ice and frost wedge pseudomorphs in the territory of the Czech Republic...
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The morphology of avalanche paths
Krause, David ; Křížek, Marek (advisor) ; Treml, Václav (referee)
An avalanche path is a landform, that is being modeled by surface snow avalanches, debris flows and other slope processes. It consists of starting zone, track and runout zone. The submitted bachelor thesis is concerned with the characteristics of avalanche paths used in literature and generates their classification. The morphometric GIS analysis is performed in the Eastern High Sudetes. The measured vlaues of 16 avalanche paths from 6 sites are statistically processed and compared. The Sudetic paths are shorter but they have similar slope in comparison with paths in alpine environment. The spatial distribution of avalanche paths is bound to lee parts of the anemo-orographic systems. The aspect is predominantly southeastern, the slope is between 20 and 30ř and the length is usually between 200 and 400 m. The path lenght depends inversely on the slope of the starting zone. There is also a relation between the avalanche path morphology and the area of alpine tundra on the etchplain above the timberline, from where the snow is being blowed to the starting zones. Key words: snow avalanche, morphometry, Eastern High Sudetes, Altvatergebirge, Glatzer Schneeberg
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Past changes of alpine treeline ecotone, Hrubý Jeseník Mts.
Leštinská, Barbora ; Treml, Václav (advisor) ; Šenfelder, Martin (referee)
The aim of this study has been to analyse the spatial-temporal dynamics of the treeline ecotone formed by Norway spruce (Picea abies) as the dominant conifer in the Hruby Jesenik Mountains since the mid 20th century until the present in order to compare vertically connected sections of the timberline ecotone. Three features have been examined within the spatial and temporal context - the age structure, the spatial structure and the age/diameter growth. Dendrochronological methods have been employed to estimate the age structure. Moreover, the remote sensing and the GIS method have been used to detect the changes of the Norway spruce cover using the archive and actual aerial orthophotographs through their vectorisation and classification incorporating both spectral and spatial information as well as the knowledge base classification technique. The comparative analysis of the archive and actual orthophotographs has allowed to evaluate the spatial-temporal changes in the cover. The age and diameter growth relation has been established using the non-linear regression. It is established that the changes in the age and spatial structure are synchronous at all localities with a similar altitude. The younger age trees proportion is increasing with the growing altitude and the changes of the cover are largest in the...
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Site-dependent growth of Norway spruce, the Hrubý Jeseník Mts.
Boszczyková, Dita ; Treml, Václav (advisor) ; Janda, Pavel (referee)
Ring - wight chronologies of Norway spruce (Picea abies) from the twelve sites in the Hrubý Jeseník Mountains have been developed to study radial growth variability and a response to interannual climate variation. The sampled sites have been examined at three different elevations along the treeline ecotone according to the southwest and northeast aspect: in the closed-canopy forest at the lowest part of ecotone and in the tree groups at the lower and upper part of ecotone. The results have shown that the radial increment on the south-facing slopes has been slightly larger in the closed-canopy forest, particularly with the oldest trees. There have not been any differences in increment between the southwest and northeast slopes in the tree groups. The period of growth depression was detected during the 1970s and the 1980s at all sampled sites. This decline was probably a result of the effect of the air pollution combined with decreasing temperatures. An increasing trend in tree growth since the 1990s corresponds with the increasing temperatures and increasing nitrogen inputs at the sampled site. On each site, there has been a positive relationship between the current-year radial growth and the mean monthly temperatures in the growing season. In the individual months, there is a shift from the...
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Structure of non-active sorted patterned ground in the Giant Mts.
Uxa, Tomáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Sorted patterned ground are a group of periglacial microforms which create more or less symmetrical forms due to frost action and especially repeated freeze-thaw cycles. The origin of sorted patterned ground in the Giant Mts. is presumed in late Pleistocene and they are suggested to be recently inactive (with the exception of sorted circles). Their occurrence is linked to the topmost localities with flat surfaces and intense wind action which causes low snow cover and allow deep soil freezing. The submitted diploma thesis deals with the influence of site characteristics (such as microclimatic extremity, terrain morphology and lithology) on morphology and sorting degree of sorted patterned ground. Field research was carried out along a transect tracing the microclimatic extremity gradient (represented by altitude and so-called relative snow height) in area of Mt. Luční hora in the eastern part of the Giant Mts. which in relatively homogeneous from the viewpoint of lithology and wind exposure. The transect was further extended across the Modré sedlo Saddle to the Mt. Studniční hora where there also occur various types of fossil sorted patterned ground or quasi- active sorted circles in the Modré sedlo Saddle, respectively. However, there is a variability of lithological as well as altitude...
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Long tree-ring records in Central Europe and their climatologic significance
Gregor, Tadeáš ; Treml, Václav (advisor) ; Ponocná, Tereza (referee)
Submitted bachelor thesis is considered with use of tree-ring dates for reconstruction of climatic conditions in the past. There is a review of some most important long tree-ring reconstructions worldwide and a review of long central-european tree-ring reconstructions in the tesis. Central European dendroclimatic reconstructions longer than 250 years were compared to each other in accordance with their length, statistical strenghtness and ability to preserve high- and/or low-frequency climatic signal. Resulting reconstructions were also compared in this bachelor thesis. Greater variability among temperature reconstructions is evident contrary to conformity of hydroclimatic reconstructions. Localisation of Central European chronologies, possible causes of differencies among reconstructions and comparisons with other proxy data were discussed. Keywords: tree-rings, dendrochronology, dendroclimatology, climate
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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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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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Morphological feattures of ice wedge polygons in arctic zone.
Kysilka, Tomáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Morphological features of ice wedge polygons in arctic zone Abstract This bachelor thesis deals with the subject of ice-wedge polygons including theirs morphological characteristics and conditions prerequisite for their creation. The paper states the conditions which allow and inhibit frost cracking of the ground. First part presents the conclusions of scientific literature published on the topic of permafrost, frost cracking, ice- wedges and ice-wedge polygons. Consequently the paper discusses the relation of ice-wedge polygons morphology to climate and lithology. Further the thesis analyzes morphological characteristics of ice-wedge polygonal net localized at southwest part of Banks Island, Canadian Arctic Archipelago. Acquired data and conclusions are confronted with published periglacial literature. Keywords: ice-wedge, ice-wedge polygons, frost cracking, permafrost, Banks Island, arctic zone
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