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  • Bedload transport measurements on the Maros river, Hungary
    37-41
    Views:
    162

    Sediment transport is a vital component in hydrological and fluvial geomorphological studies, however, the temporal and spatial changes in sediment fluxes, and the efficiency of bedload samplers are rarely analysed, as bedload measurements are quite difficult. The aim of the present study is to measure the bedload transport of the sand-bedded Maros River (Hungary) at low stages using the Helley-Smith bedload sampler. In order to understand the variability in the bedload transport, the water stage and discharge across the channel section were also measured. The variability of the bedload was caused by an active in-channel bar and translational sediment pulses. The created bedload transport rating curve could be applied just below 300 m3/s water discharge thus further measurements are needed to evaluate the bedload transport of higher discharges.

  • Analysis of landscape geographic impacts of potential climate change in Hungary
    41-50
    Views:
    147

    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.

  • New results on landscape boundaries
    1-11
    Views:
    56

    The correct delineation of geographical and landscape ecological units, being the fundamental territorial domains of both physical and human geography, is very important from the aspect of several other related disciplines as well. It is hard to tell how distinct landscape units, or landscape ecological units can be, from a statistical point of view. The present study investigates how welldefined (definable) geographical units (landscapes, landscape types) are in a statistical and mathematical sense. Since landscape forming factors do not exhibit distinct boundaries either, during the analysis it is better to consider them as ecotones. Integration of factors, and the unclear interpretation of present landscape boundaries do further complicate the sound mathematical evaluation of the studied geographical units. In order to resolve these problem GIS techniques were applied.