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  • Studying the development of fluvial landforms in the Berettyó-Körös Region using geoinformatic methods
    137-144
    Views:
    157

    Development of fluvial landforms from 1980 till nowadays was studied based on digital elevation maps
    (DEM) composed from contour lines of topographic maps, field data obtained by RTK GPS and aerial
    photos taken by a drone. Greatest denudation of 6-9 metres was measured in the eastern side of the
    erosional valley at Pocsaj caused by piping and mass movements. As a result, the valley widened and
    slightly deepened. Since 1980 around 1-2 metres of accumulation and erosion of similar rate have been
    measured in the secured floodplain environment dissected by abandoned beds, point-bars and swales
    at Kismarja. These values, however, rather reflect the geometric uncertainties and deficiencies of the
    contours of topographic maps than real land changes. Therefore topographic maps can give reliable basis
    for studying the development of lowland landforms only if they depict adequately large sized (minimum
    100 x 100 m) positive or negative forms with great height difference as well (minimum 8-10 m). Accuracy
    of DEMs composed from aerial photos using photogrammetric methods – taking off height faults caused
    by vegetation – is around the same as that of the models created on the basis of RTK GPS measurements.

  • Analysis of landscape geographic impacts of potential climate change in Hungary
    41-50
    Views:
    145

    Change of climate can be a remarkable turning point in the 21st century history of mankind. An important task of landscape geographic research is forecasting environmental, nature protection, land use demands and helping mitigation of disadvantageous processes from the aspect of society. ALADIN and REMO numeric climate models predict strong warming and lack of summer precipitation for the area of Hungary for the period between 2021 and 2100. There is a predicted growth in frequency of extreme weather events (heat waves, droughts hailstorms). Changes have been forecasted using data presented in table 1. For analyses of complex landscape geographic impacts of climate change the area of Hungary have been divided into 18 mesoregions with 5.000-10.000 km2 area each (figure 1). The main aspect of choosing the regions was that they should have homogeneous physical, geographic and land use endowments and, for this reason, they should react to climate change the same way. Relationships between landscape forming factors and meteorological elements examined by us have been taken into consideration. Results of analyses of impacts of the meteorological factors on the changes of relief through the mass movements are presented in this paper. Changes of landscape sensibility of mesoregions to mass movements have been presented in the last chapter for the periods between 2021-2050 and 2071-2100 according to numeric climate models.