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Holocene history of Arctic lakes
Roman, Matěj ; Nývlt, Daniel (advisor) ; Kavan, Jan (referee)
Holocene history of Arctic lakes Abstract Palaeolimnology in the Arctic has achieved a considerable progress in the last decades. The Arctic has changed markedly since the Last Glacial and glacier retreats caused formation of a great number of diverse lake types. Lakes of glacial origin, thermokarst lakes, fluvial lakes and lakes on raised beaches occur most often here. Palaeolimnological methods applied to the high latitude areas are used for the study of the history of individual lakes. Methods of correlation of sedimentary cores and basic interpretation of proxy records such as magnetic susceptibility, diatom biostratigraphy and content of carbon and sulphur were applied on sediments of Garmaksla Lake, Svalbard Archipelago. Climatic and ecological shifts including the Little Ice Age termination and recent warming were registered in proxy values. Keywords: lakes, palaeolimnology, palaeoclimatology, environmental changes, Holocene, Arctic
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Holocene history of Arctic lakes
Roman, Matěj ; Nývlt, Daniel (advisor) ; Kavan, Jan (referee)
Holocene history of Arctic lakes Abstract Palaeolimnology in the Arctic has achieved a considerable progress in the last decades. The Arctic has changed markedly since the Last Glacial and glacier retreats caused formation of a great number of diverse lake types. Lakes of glacial origin, thermokarst lakes, fluvial lakes and lakes on raised beaches occur most often here. Palaeolimnological methods applied to the high latitude areas are used for the study of the history of individual lakes. Methods of correlation of sedimentary cores and basic interpretation of proxy records such as magnetic susceptibility, diatom biostratigraphy and content of carbon and sulphur were applied on sediments of Garmaksla Lake, Svalbard Archipelago. Climatic and ecological shifts including the Little Ice Age termination and recent warming were registered in proxy values. Keywords: lakes, palaeolimnology, palaeoclimatology, environmental changes, Holocene, Arctic
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Freshwater macroinvertebrates and their use for assessment of environmental changes in running waters
Kolaříková, Kateřina ; Stuchlík, Evžen (advisor) ; Matěna, Josef (referee) ; Porcal, Petr (referee)
The dissertation thesis consists of five articles, bringing together results from investigations of macroinvertebrates in running waters. The use of freshwater macroinvertebrate organisms to assess environmental changes was based on the following facts: a) the presence/absence of taxa provide information about abiotic factors and/or about the pollution status of the site, b) they are indigenous and sedentary species, so that the environmental implications can be related to the site they live on, c) the organisms accumulate xenobiotic elements or compounds, thus reflecting the contaminant level in the environment. Localization of the sampling sites was related to the "hot-spots" of environmental problems. The particular investigations were carried out in the Elbe River catchment and in the Czech mountains on the selected headwater streams of the GEOMON network of the Czech Geological Survey. The Elbe was considered one of the most polluted rivers across Europe in the second half of the past century until the socio-economic transformation after 1989. The headwater streams in the Czech Republic were chosen with respect to the problem of acidification. The ability of bioaccumulation of xenobiotics in macroinvertebrate organisms was used to assess the long-term load of the Elbe ecosystem with trace...
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Percepce environmentálních změn : regionální aspekty /
Duží, Barbora
This dissertation thesis deals with two key research topics. The first is perception of environmental change and its negative impacts on human property, infrastructure and even human lives. Specifically, we research the whole scale of extreme weather events, framed as hydrometeorological or climate extremes. The second part of dissertation focus on societal adaptation to these impacts. Both topics are researched on household level with regard to regional conditions. Empirical part of the research was realized within Bečva river basin in order to find out the state of adaptation on regional and household level. Within environmental sociology research, we connected with 605 household representatives from 22 municipalities and 25 key stakeholders from target area. The aim of the dissertation was to introduce actual scientific evidence about perception of environmental change, with focus on climate extremes and ways of societal adaptation.
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Stanovení adaptačního potenciálu chřadnoucích smrkových porostů v oblasti Kysuc (Slovensko) vůči environmentální změně
Plevková, Miroslava
The extended decline of Norway spruce forest stands in the Kysuce region, caused by the synergistic action of natural and anthropogenic stress factors, has been observed in the last decades. The aim of this thesis was to try to estimate the adaptation potential of declined spruce stands towards environmental change on the permanent research plots (TVP) on the basis of the identification of the stress response categories of stands and the description of their regeneration ability. On seven TVP, established in the Kysuce region (Veľký Polom, Klokočov, Zákopčie, Javorské), the site and forest stand characteristics, natural regeneration, and root rot occurrence were investigated. In particular, characteristics of the crowns (defoliation and transformation of the crown structure) were paid a great attention. According to obtained results the Maion spiral was precised for the Kysuce conditions. The results of the thesis indicate that the decline process will be continuing in all studied forest stands; according to the adaptation potential estimation, it is expected that these stands will disintegrate till 40 years. Fortunately, all these forest stands have a capability of natural regeneration, especially on the PRP Zákopčie, Javorské and Klokočov. However, only the pure Norway spruce forest stands, susceptible to subsequent climate change impacts, will be a product of this natural regeneration.
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