Saját polc tartalma
Összesen 1 találat.
Négyesi Gábor (geográfus)
Integrated spatial assessment of wind erosion risk in Hungary / Négyesi Gábor, Pásztor László, Laborczi Annamária, Kovács Tamás, Bihari Zita
Wind erosion susceptibility of the Hungarian soils was mapped on national level integrating three factors of the complex phenomenon of deflation (physical) soil (features), wind (chracteristics), landuse/landcover). Results of wind tunnel experiments on erodibility of representative soil samples were used for the parametrization of countrywide map of soil texture compiled for the upper 5 centimeter layer of soil, which resulted in a map representing threshold wind velocity exceedance. Average wind velocity was spatially estimated with 0.5' resolution using the Meteorological Interpolation based on Surface Homogenized Data Basis (MISH) method elaborated for the spatial interpolation of surface meteorological elements. The probability of threshold wind velocity exceedance was determined based on values predicted by the soil texture map at the grid locations. Ratio values were further interpolated to a finer 1 ha resolution using sand and silt content of the uppermost (0-5 cm) soil as spatial co-variables. Land cover was also taken into account excluding areas which are not relevant from the aspect of wind erosion (forests, water bodies, settlements etc.) to spatially assess the risk of wind erosion. The outcome of wind speed exceedance calculations was the probability value of wind velocity exceeding critical values on an hourly level during the observed 13 years in each point of the grid network (Fig. 5). According to the map, spatial variability is relatively high throughout the country. Values in general range from 0% to above 2.5% in relation to wind climatology, landscape, soil properties and land cover. According to the categorized wind-erodibility map five distinct territories can be identified in the country with typically higher wind erosion risk: 1. The Nyírség is an ancient alluvial fan, its area is about 5,100 km2 and consists of mainly sandy soils and its different variant. About one third part of the area are covered by forests (mainly the eolian forms), but there is difference in this regard in regional distribution, because territories covered by sandy loam, loam and silty loam are under agricultural cultivation and are more endangered by wind erosion. 2. The Duna-Tisza Interfluve is about 10,000 km2 and also consists of sandy soils and its variant. A significant discrepancy to the Nyírség that this area is poorer in precipitation (500-550 mm) and there are drought periods in many years. As a consequence of its dryer climate, its forest cover is sparser than in Nyírség. 3. The glacis in the foreground of the Transdanubian Mountains are affected by wind erosion because of mainly two reasons. In one hand they are covered by sandy soils, on the other hand the wind velocity is the highest in Hungary ? because this region is exposed perpendicularly to the dominant winds blowing from northwest. 4. The Inner-Somogy is about 3,000 km2 . However, it has more precipitation, than Nyírség and Duna-Tisza Interfluve, according to the alluvial fan origin of the area, it is also covered by sandy soils, which make it more endangered by wind erosion. 67 5. The Transdanubian loess region is also situated in the Transdanubian region and consists of loess. The productivity of the soils formed on them is outstanding, so the dominant land use is arable lands. This territory is also exposed perpendicularly to the winds blowing from northwest, which together with the seasonally uncovered and extended agricultural areas make it more susceptible to wind erosion.
spatial soil data
wind erosion mapping
wind velocity data
Geomorfologický sborník 16 : Proceedings of the conference State of geomorphological research in 2018 / ed. Zdeněk Máčka, Jaroslava Ježková, Eva Nováková, František Kuda. - p. 66-67. -
Intézményi repozitóriumban (DEA) tárolt változat
Corvina könyvtári katalógus v7.5.23
Minden jog fenntartva.