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  • Author or Editor: György Várallyay x
  • Chemistry and Chemical Engineering x
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Sustainable land use and rational soil management, including an up-to-date soil moisture control requires continuous actions. This permanent control may prevent, eliminate or at least reduce undesirable soil processes and their harmful economical/ecological/environmental/social consequences; utilizing the unique soil characteristic, resilience, may satisfy the conditions for the “quality maintenance” of this “conditionally renewable” natural resource. Control can be efficient only on the basis of comprehensive risk assessment, impact analysis and exact prognosis. These have to be the main research priorities! The successful prevention, elimination or moderation of undesirable soil degradation processes and extreme moisture regimes can be efficient only in a well-coordinated multidisciplinary international cooperation in the Carpathian Basin. The realization of the sustainability concept in the rational land use and soil management gives reality for a better life: healthy, good quality food, clean water and pleasant environment.

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In the hydrogeologically closed Carpathian Basin subsurface waters have particular importance in the salinization/alkalization processes. In the poorly-drained low-lying areas the capillary flow transports high amounts of water soluble salts from the shallow, „stagnant” groundwater with high salt concentration and unfavourable sodium-carbonate(bicarbonate) type ion composition to the overlying soil horizons. Due to the strongly alkaline soil solution, the Ca and Mg salts (mostly carbonates and bicarbonates) are not soluble and Na + became absolutely predominant in the migrating soil solution which leads to high ESP even at relatively low salt concentration. High Na + saturation of heavy-textured soils with high amount of expanding clay minerals results in unfavourable physical-hydrophysical properties and extreme moisture regime of these soils, which are their main ecological constrains and the limiting factors of their fertility, productivity and agricultural utility. The simultaneous hazard of waterlogging or overmoistening, and drought sensitivity in extensive lowland areas, sometimes in the same places within a short period, necessitates a precise, “double function” soil moisture control against their harmful ecological/economical/social consequences. Most of the environmental constrains (including salinity/alkalinity/sodicity) can be efficiently controlled: prevented, eliminated, or - at least - moderated. But this needs permanent care and proper actions: adequate soil and water conservation practices based on a comprehensive soil/land degradation assessment. It includes continuous registration of facts and changes (monitoring); exact and quantitative knowledge on the existing soil processes, their influencing factors and mechanisms.

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