National Repository of Grey Literature 41 records found  beginprevious32 - 41  jump to record: Search took 0.01 seconds. 
Diatoms of Quaternary Sediments from the Lake Komorany
Poštulková, Anna ; Rajdlová, Hana (advisor) ; Houfková, Petra (referee)
Diatoms are unicellular phototrophic organisms, whose siliceous frustules preserved in sediment have broad palaeolimnological application. Sediments of former Komořany Lake count among the richest Czech sediments in quaternary diatoms. This already destroyed locality is examinated in search and practical part of work. The search part contains characterization of diatoms and locality Komořany Lake. Diatoms are described in paleontological point of view, that is why the main attention is payed to morfology of frustule, their ecology and application in geological sciences. However, for complete image of this various group, the new pieces of knowledge about their taxonomy or evolution are not overlooked. The root of the work is summarization of accessible literature about Komořany Lake with special attention to research of diatoms. In practical part diatom valves were isolated from samples of sediment from profile PK-1-W, 18 long-lived sections were prepared and 6 of them were used for taxonomical determination. The 47 taxons of diatoms were found, 7 of them had not been included in work of Řeháková (1986). The synonymy of taxons are created in comparison with results of Řeháková (1986). From taken pictures are created 6 taxonomical plates. Key words: diatoms, Bacillariophyceae, Komořany Lake,...
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.
The Quaternary Paleoecological Analysis of the Soos National Nature Reserve
Rajdlová, Hana ; Holcová, Katarína (advisor) ; Novák, Jan (referee)
The Quaternary Paleoecological Analysis of the Soos National Nature Reserve The aim of this proposed diploma thesis is to describe the structure of diatom communities in the diatomite deposits of the Soos National Nature Reserve and compare the finding of this thesis with those of older publications. Another aim was to reconstruct the history of the basin trough with the outputs of diatom analysis accomplished in the 3,4 m long sediment profile. The similarity of diatom communites in individual diatomite types was also tested. Key words: subfossil diatoms, Soos National Nature Reserve, paleolimnology, Late Glacial, Holocene
Forest evolution in Central Europe during the Holocene periode
Švábová, Barbora ; Šefrna, Luděk (advisor) ; Matějček, Tomáš (referee)
The work deals with the forest as an ecosystem where relationships take place, which are influenced by abiotic and biotic factors. Great attention is paid to the climate, which affects not only the distribution of biomes. Its constant changes have an impact on the species composition of forests and human society. By the effects of the climate, the Holocene period was divided into sub-stages. Man also played a significant role in the conversion of the central Europe forest and changes it even now. That is why this work devotes a considerable part of it to this influence. Great changes of the forest began with the emergence of agriculture, which was the first impulse for the beginning of deforestation. Examined are the ways of prehistoric and modern economy. With the loss of trees came an idea of protecting the forests. As an example of possible further effect on the forest, the influence of some pathogens is presented.
Postglacial vegetation history of local phenomena in western Bohemia
Švarcová, Markéta Gabriela ; Kuneš, Petr (advisor) ; Kozáková, Radka (referee)
In the sense of postglacial vegetation development, western Bohemia represents one of the least studied regions in the Czech Republic. This area, however, represents a supposed migration route of trees towards northern Europe during the Holocene. The most appropriate area for testing of such proposal might be western Sudetes with Slavkovský les protected landscape area in the Karlovy Vary region. Postglacial vegetation history was studied on the basis of two sedimentary profiles - from the fen bog near Číhanské prameny springs and from the vicinity of Mnichovské hadce serpentines from the nature reserve Mokřady pod Vlčkem. Percentual as well as influx diagrams were constructed on the basis of results of standard pollen analysis. Comparison of these results with the data from other suitable profiles enabled reconstruction of migration history of main tree taxa. The Číhaná profile reflects the period from the Older Dryas up to the Atlantic. The oldest Holocene forest was formed by the dominant Pinus, while Corylus was joining already in the Preboreal. Quercetum mixtum folowed in the begining of the Boreal and spruce quickly gained dominance in the Atlantic. The sedimentation process was probably finished due to rapid accumulation of sediments followed by spontaneous drainage ending with spruce and alder...
History of vegetational development in the Cheb basin from sedimentary record of the SOOS National Nature Reserve
Suda, Tomáš ; Kuneš, Petr (advisor) ; Bešta, Tomáš (referee)
Vegetation development in the Cheb basin ( W Czech Republic) recorded in the sediments of the SOOS ational ature Reserve This thesis focuses on palaeoecological research of quaternary sediments in the Soos National Nature Reserve (Cheb basin, NW Czech Republic). Quaternary history of this locality is poorly known, despite it is a valuable and protected area with high natural qualities. The Soos basin is also known for its unique geological record, which is expected to cover information on landscape dynamics at least during the Holocene. A lake existed in the Soos basin enabling accumulation of diatomite and peat sediments of a broad palaeoecological potential. Records were analysed with method of pollen analysis and were dated using 14C. The results of this study bring information about vegetation development in the area of Cheb basin as well as development of lake ecosystem. It also gives a new insight on lake's origin and its age. The accumulation of peat sediments started in the Preboreal period and was continuous at least until the Atlantic following with a hiatus, therefore further detection of vegetation development is impossible. The beginning of diatomite accumulation, as well as the existence of the lake goes back to the Bølling interstadial, according to radiocarbon dating. However, this...
The use of diatoms (Bacillariophyta) in paleolimnology
Aubrechtová, Martina ; Píšková, Anna (referee) ; Kulichová, Jana (advisor)
This thesis is a literature review summarizing methodology and the possibility of use of diatoms (Bacillariophyta) for paleoecological reconstructions of extinct lacustrine ecosystems. In addition, the theoretical part of the thesis is devoted to basic characteristics, evolutionary history and ecology of the group, lakes and the fossil record. In the practical part, two samples of sediments of a fossil lake that has been discovered and studied within the Morava Project in Strážnické Pomoraví are compared.
The Holocene Climatic Optimum in Northern Africa: Geoarchaeological research of the environmental and cultural interaction
PARVONIČOVÁ, Lenka
This research work summarises results of geological and archaeological investigation in the Sahara Desert. The analyses of paleoclimatic and paleoenvironmental deposits are combined with archaeological records of the human occupational development during the Early and Middle Holocene. The period characterised by higher humidity is called The Holocene Climatic Optimum. The region of the Eastern Sahara consisted of Libyan, Egyptian, Sudanian and Chadian area provides unique opportunities to study the relationship between climate changes and human occupation.
Prehistory and history of human impact on landscape relief: And overview of current directions in the study and the importance of case studies
BUMERL, Jiří
Humans became an important factor in the development of Holocene relief. They began to significantly influence a plant cover and retention of the landscape with the advent of agriculture. The consequences of deforestation and an economic land use on erosion and accumulation processes are evaluated by comparing case studies from areas of Germany, Czech Republic and Poland. The main erosive processes belong to the end of Eneolithic, Late Bronze Age, the end of the Roman Period, and early Middle Ages in the area of interest. On a microscale, a stronger influence of archaeological situations arisen before the start of the erosion events and a substantial reduction of artefacts stored in situ can be expected.
Oxygene regime of pools and oxbows in the aluvium of the lower reach of the Dyje River in winter 1999/2000
Horák, Václav ; Machatka, T.
This study is focused on the oxygene regime of pools and oxbows which are found in the Dyje River aluvium (r. kms 0.0 - 18.0). The oxygene conditions determine the quality of environment of these biotops for fish. In total 4 pools, 3 oxbows and 1 river were investigated.

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