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This paper had a primary task, namely “Proposal of a methodology for the process of preliminary assessment of flood risk – a methodological procedure for preliminary flood risk assessment from flash floods with respect to the need for its updating following from directive 2007/60/EC and its application in the conditions of a modelled territory”. The methods which are used in the contribution emerge from practical experience as well as from knowledge obtained from the available literature and consultations with experts dealing with the given problem in practice. The foundations of flood risk assessment are hypotheses on the impact of physiogeographical attributes of basins on the origin of floods. The conceptual framework for flood risk assessment of flash floods comes from the definition of a multidimensional conception of flood risk. The proposed methodology consists in the identification of critical points and contributing surfaces from the viewpoint of creation of a concentrated surface flow from flash floods and their adverse impacts on the built-up areas of a municipality. The primary goal of the assessment of risk of contributing surfaces was determining the riskiness of the locality with an ordinal degree (i.e., low, moderate, and high) and providing a foundation for a second stage, called controlling risk. The resulting risk of contributing surfaces is determined as a combination of danger and vulnerability according to a set matrix. Processing and analysis of the input data as well as visualization of the achieved results is carried out in the GIS environment (ArcGIS 9.3, 10) in integration with a spreadsheet of Microsoft Excel. [ABSTRACT FROM AUTHOR]

For the geodetic survey of the terrain surface, the use of conventional surveying methods and instruments is common. New technologies, such as e.g. UAVs and their combination with a digital camera, bring new opportunities also in the documentation of Earth’s surface. This combination of technologies allows for the use of low-cost digital photogrammetry to document the Earth’s surface in relation to mining activities. The aim of the research presented in this paper is to analyze the accuracy of the digital elevation model (DEM) obtained using low-cost UAV photogrammetry. The surface mine Jastrabá (Slovakia) was chosen as the test area. The mine has morphologically dissected surface and is thus suitable for verifying the use of UAV photogrammetry to capture fairly intricate details on the surface. The research, which has been carried out, showed that the model created from photogrammetric data from the UAV achieves the accuracy required by current national legislation. From the selection of the test consisting of 237 points, only 3 points failed the conditions for the accuracy of the detailed points. These results indicate that the combination of low-cost UAV and a digital camera may be used as a viable alternative for the collection of data with the goal to document surface structures and to form 3D models formed from this data. The use of UAV in a photogrammetric survey of the mine brings new opportunities for the creation of documentation, because with this technology we can measure the entire surface in detail, create orthophoto maps of the entire area and document inaccessible parts of the area such as sludge dumps, and steep slopes. [ABSTRACT FROM AUTHOR]

The most important anthropogenic influences on climate are the emissions, changes in land use, such as urbanization aural areasnd agriculture. The urban environment has distinctive bioclimatical factors in relation to rural areas. The process of urbanization alters natural surface and atmospheric conditions. Urban areas are characteristic by increased rainwater surface runoff, increased temperatures and decreased evaporation. Exactly evaporation warms the rural surface more than the urban. The paper concerns on the impacts of urbanization that are evaluated by observations in cities with those in rural areas – not so populated and with smaller built areas. We use and asses the difference between trends in monthly average temperatures and trends in monthly precipitations in the cities and the corresponding trends in rural areas. For the trend analysis, the Mann-Kendall nonparametric test is used. Our results show differences in trends in villages and cities. Observed are increased trends in temperature and decreased trends in precipitation due to urban and land-use changes. [ABSTRACT FROM AUTHOR]