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Anthropogenic impact on landscape transformation and vegetation changes reflected in pollen spectra from Central-Eastern Europe.
Jamrichová, Eva ; Kuneš, Petr (advisor) ; Dreslerová, Dagmar (referee) ; Marinova, Elena (referee)
The present thesis focuses on the impact of human communities on postglacial vegetation changes and landscape transformation in the region of Central-Eastern Europe. The main aim of the study was to evaluate how past human activities are reflected in pollen spectra from different types of mostly small-sized sites. Since the Middle Holocene onwards, human impact contributed to the formation and spread of various types of open habitats, altered the vegetation composition by introducing new species, influenced forest structure and supported the acceleration of geomorphic processes such as soil erosion or sediment accumulation. Human-induced alteration of the landscape cover and vegetation composition is reflected in pollen spectra, but it is often difficult to identify. Considered as direct evidence of human activities are the presence of pollen grains of cultivated plants in pollen spectra. Besides, there are several indirect traces of human impact on the landscape such as the spread of secondary anthropogenic indicators (apophytes), fluctuation in pollen curves of trees as a consequence of change in landscape cover or woodland composition, increases of micro-charcoal particles due to human-induced fire or erosion processes. Chapter 1 presents confirmation of the assumption that Neolithic human...
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Long-term disturbance dynamics of spruce forest in High Tatra Mts.
Beranová, Jana ; Kuneš, Petr (advisor) ; Jamrichová, Eva (referee)
Spruce forest is an important production ecosystem for our civilization. Its development can be affected by three main types of disturbances: forest fire, windstorms and spruce bark beetle attack. Experiences with a massive and long-term attack of spruce bark beetle in the Šumava mountains and a strong windstorm in 2004 in the spruce forest in the High Tatra provoke questions, how natural are such severe disturbances. To understand the current development of forest ecosystems, it is necessary to study past structure of these forests and frequency of forest disturbances. This work is about locality Tatranská Lomnice located in the High Tatra mountains, in the belt of mountain spruce forest. In my work, I used mainly pollen and plant macro-fossils analyses. I compared my data with disturbance information originating from dendroecology for windstorms and from charcoal analysis for fires. My research found that according to the pollen assemblages, most of the disturbances did not have strong influence on the forest composition, and most likely they only caused the forest thinning. The most significant fire occurred around 1420. The most significant wind disturbance probably occurred in 1890. The was not found any effect of spruce bark beetle. In the past millennium disturbances affected spruce forest...
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Changes in vegetation of Karpaty since glacial maximum - identificaition of main trends accesibility of data and gap in knowledge
Beranová, Jana ; Kuneš, Petr (advisor) ; Jamrichová, Eva (referee)
The Carpathian Mountains are great range in Europe. This rewiew is target to identify main evolution trends of vegetation i Carptahian Mountatins. I studied materials whitch was concetrate to pollen analysis and malacological finds. Based on this materials I found that in the stadial dryas periods there were climatic conditions for small forrest islands mainly formed from genus Pinus and Larix. In the interstadial periods the different climatic conditions permit forrest propagation and became denser. Transitions from pleistocen to holocen was nearly similar to the situation in interstadial period. But later in the holocene the density of the forest is growing more and dominant of late glacial forest was replaced mainly by the spurce. Population of plants that survive the glacial in the Carpathian mountain growing as same as and new species that survived glacial in warmer localities. In the subatlantic and especially in the few last decade the human efect is important and can be found in the pollen analysis. On the research of plant evolution in Carpathian mountain is necessary to continue, mainly on identification and analysis new localities. This large area is unequaly covered by localities.
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Phytolith spectra of the recent vegetation in north-east Africa: testing the potential of phytolith analysis for palaeoecology
Kuncová, Kristýna ; Pokorná, Adéla (advisor) ; Jamrichová, Eva (referee)
Phytoliths are mostly formed by groundwater silica carried upwards in a plant's vascular system and consequently accumulated in different parts of the plant. After the plant's death, the phytoliths shaped in specific morphotypes are released into the soil. Phytolith assemblages found in the soil can therefore provide information on the previous vegetation cover. The use of phytoliths as a paleoecological tool is based on their high stability in a broad spectrum of environments, even in arid conditions which are usually not suitable for preservation of pollen grains and plant macro-remains. Analysis of surface phytolith assemblages linked to the parallel study of modern vegetation is offering a good opportunity to refine our knowledge of paleoecosystems of NE Africa by evaluating the interpretation value of the fossil data. Modern phytolith assemblages are usually interpreted by using their phytolith ratio to estimate the density of tree cover, the aridity, and the proportion of C3 and C4 grasses (Barboni et al. 1999). Here we show a comparison of soil phytolith assemblages on a 400 km long climatic gradient reaching from semidesert to short grass savanna. And we also show local variability in phytolith assamblages at one of localities in comparision with grass reference collection. This master...
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Changes in vegetation of Karpaty since glacial maximum - identificaition of main trends accesibility of data and gap in knowledge
Beranová, Jana ; Kuneš, Petr (advisor) ; Jamrichová, Eva (referee)
The Carpathian Mountains are great range in Europe. This rewiew is target to identify main evolution trends of vegetation i Carpathian Mountaitns. I studied materials whitch was concetrate to pollen analysis and malacological finds. Based on this materials I found that in the stadial dryas periods there were climatic conditions for small forrest islands mainly formed from genus Pinus and Larix. In the interstadial periods the different climatic conditions permit forrest propagation and became denser. Transitions from pleistocen to holocen was nearly similar to the situation in interstadial period. But later in the holocene the density of the forest is growing more and dominant of late glacial forest was replaced mainly by the spurce. Population of plants that survive the glacial in the Carpathian mountain growing as same as and new species that survived glacial in warmer localities. In the subatlantic and especially in the few last decade the human efect is important and can be found in the pollen analysis. On the research of plant evolution in Carpathian mountain is necessary to continue, mainly on identification and analysis new localities. This large and geographically complicated need informations from new localities.
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