1 Salinization and amelioration possibilities of salt affected soils on the Great Hungarian Plain

soils (SAS) cover about 1 million ha in Hungary. SAS with structural B-horizon (“meadow solonetz soils”) represent the most wide spread group of sodic soils in Hungary. Most of them are located in the Trans Tisza Region (geographical region of Hungary east of River Tisza). About 50 percent of these soils have been reclaimed and used as arable land until now. The practice of reclamation of SAS is two centuries old. A book by TESSEDIK (1804) was the first guide on this topic. In spite of this long history and the results the revaluation of the research is important because of the changing economical and ecological situation. For the purpose of improving the economics of agricultural production, eliminating the overproduction, lightening the environmental loads the reduction of the arable land area is planned now. In the Trans Tisza Region this reduction will concern mainly the arable lands on SAS. SAS are suitable for arable land use only after amelioration. Reclamation of SAS is usually more expensive than liming of acid soils. It is especially costly if beyond the use of chemical amendments and deep loosening also regulation of the groundwater level by subsurface drainage is necessary. For a well established land use decision- among others- the following questions must be answered