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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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Freeze-thaw processes, temperature and moisture trends in earth hummocks
Kodríková, Anna ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Earth hummocks are nonsorted patterned ground types. This thesis is primary focused on the study of temperature regime particularly during freeze-thaw process and also on factors that affect its non-uniformity. Secondary, it refers to the relation between temperature and moisture regime, morphometric characteristics of earth hummocks and their geographical expansion in the world. The information from the literature search is applied to the results from temperature and moisture measurements of the earth hummocks in depths 5 - 40 cm in the Hrubý Jeseník Mountains - Keprník peak in 2005 - 2010. The results show that many factors affect the non-uniformity of temperature regime in different parts of earth hummocks. The most important of them are: the shape of the earth hummock, the aspect orientation, the distribution and the height of snow cover, the wind exposure and the presence of vegetation. There is an interaction between the soil moisture content and the temperature regime, and they are mutually affected. The obtained results from the Keprník study area are compared with the literature data about the earth hummocks in the world. Key words: patterned ground, earth hummock, temperature regime, moisture, regelation, Keprník peak, Hrubý Jeseník Mountains
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Dendrochronological dating of catastrophic slope movements
Tumajer, Jan ; Treml, Václav (advisor) ; Burda, Jan (referee)
Mass-movements are one example of natural processes that can pose a serious risk for human beings and their possessions. Dendrochronology, a method capable of their reconstruction, can provide parameters of former events, which can be used for planning protective measures. The possibilities for the application of dendrochronological methods have been tested by means of meta-analysis of electronic and printed scientific articles and a case study focused on former avalanche activity in Schustler's avalanche path (Labský důl, Krkonoše Mts.). The main conclusion of the first one is the clear spatial disproportion of the recent dendrogeomorphological research activities - e.g. the dating of avalanches is typical for mountains of Montana (USA); the Alpine region (mainly Switzerland), on the other hand, absolutely dominates in the research of debris-flows. In the case study, the analysis of material with well-chosen indicators led to high accuracy results comparable with the results of scientific articles focused on avalanches, and made the identification of 14 years (in the period 1953-2007) with potential avalanche acitvity possible. Although methods of dendrogeomorphology are usually neglected in the research of avalanches in the Czech republic, their great potential for future applications is shown....
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SPATIAL PATTERN OF TREES WITHIN TREELINE ECOTONE
Zákravská, Šárka ; Treml, Václav (advisor) ; Demková, Katarína (referee)
The main part of my bachelor thesis is focused on treeline advance and on its spatial pattern especially. The theoretic part is consisted of a description of basic properties, hypothesis of treeline formation, current treeline movements in chosen European mountains and their potentional explanations. The aim of the practical part was to discover whether the type of spatial pattern affects treeline dynamics. Namely, the western part of the Giant Mountains was taken as a surveyed teritory. Ortorectified aerial photographes from years 1936 and 1964 were used when doing comparison. Spatial pattern was counted by "Ripley's K-function" and by the method of "Average Nearest Neighbour" on 110 defined squares (size 30 m) in the expanding part of the ecotone and on 110 defined squares in its stagnation part. Results don't indicate that some type of spatial pattern support treeline advance. The same spatial pattern was found both in major parts of stagnation and the expanding part of the ecotone.
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Past dynamic of alpine treeline ecotone in the eastern part of the Krkonoše Mts.
Jungrová, Alena ; Treml, Václav (advisor) ; Chuman, Tomáš (referee)
4 Abstract The purpose of the diploma thesis is the analysis of changes in the alpine treeline ecotone with focus on the age structure and cover of the Norway spruce (Picea Abies) in the Giant Mountains in the 20th century. The altitudinal position and the tree density of the alpine treeline ecotone is a sensitive indicator which reflects the human impact as well as the climatic and air pollution changes. Methodical approach included the measuring of the age structure of the Norway spruce by using dendrochronology. In addition the changes of the spruce cover were evaluated from a series of aerial photographs dated 1936, (1953) 1964, 1985 and 2002. Those photographs were orthorectified and classified. The age distribution in the majority of the sample locations is irregular with some prominent peaks that are corresponding to the periods of good conditions and dips pointing out to the periods of disturbances. There is an evident peak during the 30s and 40s which is the same period of the increase of average temperatures of the growing season. On the contrary, depression during the 70s and 80s is detected only in the case of closed-canopy forest. The increasing number of trees during the 90s is related to the decreasing air pollution and to the higher average temperature. Relatively young age structure of the...
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Alpine treeline dynamics in relation to slope aspect, western Giant Mts.
Píro, Lukáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
In eight selected habitats in the Western Giant Mountains (area of peaks Kotel and Violík) was studied growth of individuals of Norway spruce (Picea abies) in ecotone of alpine treeline. There were selected four habitats in two locations (tree groups and close canopy forest) in the south exposition and four habitats in two locations in the north exposition. With use of size of radial growth and other dendrometrical characteristics was studied differences in growth of trees depend of slope exposition and location of the habitats (tree groups and close canopy forest). There were compiled the standard and residual chronologies. Further was studied the response function of radial growth and temperature characteristics, especialy mean temperature of growing season. It was found the positive a negative pointer years, representive years with extreme ring width, and response function of pointer years indexes and temperature characteristics. Last step was to analyze the tree age structure in studied habitats. There were found statistically significant differencies in radial growth between north and south slope exposition in the close canopy forest position in years 1959 - 1998, although radial growth on south side was larger all the spotted time. In tree groups was radial growth larger in north slope...
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Repletion Municipal Plan as a Planning Tool - Documetation vs. Reality
Hrudková, Magdalena ; Perlín, Radim (advisor) ; Treml, Václav (referee)
Spatial planning is a science that draws from the natural, technical and social sciences, and also penetrates into the sphere of economic, social and environmental spheres. It also responds to changes in social conditions. The task of land use plans, as long document is to respond to past developments, contemporary trends and to support future development. Regional plans made in the 90 years later, in the environment of the new political regime had an important role to capture and promote regional development. Among the cities which have sourced a new political conditions, land use plan, and belonged to Plzen. The effectiveness of Pilsen development plan of 1995 was forecast over 15 years, until last year. In the case of efforts on the evaluation of the development plan, it is necessary to take into account the changing conditions in various companies. If we respect the impact of these changes, then evaluate the good or bad the plan is not possible. For this reason, in this work are treated to a sort of reflection on the repletion of the city plan of Pilsen.
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Tree-ring chronology of Norway spruce, a study from the Eastern Krkonoše Mts.
Janda, Martin ; Kolář, Tomáš (referee) ; Treml, Václav (advisor)
3 ABSTRACT Presented thesis is focused on the development of Norway spruce (Picea abies (L.) Karst.) dendrochronologic standard for the high elevation zone of the Eastern Krkonoše Mts.. Samples were taken from individuals growing either in supramontane forest or in the treeline ecotone. Additional increment cores were sampled in old cottages and chalets. Various elements of roof constructions and timbering were the source of dendrochronologic material. Aim of the thesis was to develop long and reliable tree-ring chronology using standardisation techniques which retain also lower frequency climate variations. Two standard tree-ring chronologies were developed - first using double detrending standardisation (DD, 1792-2006), second using regional curve standardisation (RCS, 1811- 1970). Analyzed historic material significantly differs from tree-ring curves derived from standing trees, thus achieving the composite chronology was impossible. Cottage no. 9 in Svoboda nad Úpou is with its origin after AD 1711 outstanding among thirteen successfully dated historic buildings. Both RCS even DD chronologies retain lower frequency variations. DD chronology can be successfully used in events and some buildings dating. Response function analysis was made using monthly instrumental records from the Sněžka meteorological...
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Changes in land cover in the summit part of the Mt. Oblík (České Středohoří Mts.)
Kuna, Petr ; Demková, Katarína (referee) ; Treml, Václav (advisor)
Oblík, with his height 509.25 meters above sea level, is the dominant feature of the southwestern part of the České středohoří Mts. which is often referred to as Lounské středohoří Mts.. Geological environment and characteristic climatic conditions prevailing during the last Quaternary glaciation here prompted the creation of natural forest-free areas that are in form of isolated fragments of land preserved to this day. Oblík is one of the most important steppe sites in our area. Ever since the arrival of Neolithic man, the whole region Lounské středohoří Mts. influenced by human intervention. It can be assumed that the influence of grazing helped preserve important sites for steppe at Oblík. From preserved material can be observed the existence of forest on the northern slope. Currently, they are dominated by oak forests with trees such as oak winter (Quercus petraea) and oak (Quercus robur) with an admixture of hornbeam (Carpinus betulus). Contrast, the southern slopes covered many steppe species such as pheasant spring (Adonanthe vernalis), steppe sedge (Carex scales) or a total of five kinds of Stipa (Stipa sp.) and others. On Oblík there are several rare and endangered species that are of interest to the special protection of this National Nature Reserve. At present, the slopes with steppe...
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