The role of soil minerals in optimal land use [antikvár]

Pál Stefanovits Gödöllő Agricultural University The reasonable and optimál land use has particular importance in the present situation of the Hungárián agriculture because without it the economic and high quality agricultural production can not be performed. This optimál land use is basically determined by the soil and the landscape in which the production takes place. The double function of soil sueh as providing the basis of agricultural production and high quality environment requires intense knowledge of the soil as a phenomenon of nature. This is impossible without the thorough knowledge of the mineral fraction of the soil. More than 95% of the soil components belongs to the mineral fraction. Without ignoring the role of organic matter in the soil the importance of the mineral fraction has to be emphasized. The mineral fraction consists of primary and secondary minerals. Primary minerals has been inherited from the parent material on which the soil was förmed. Secondary minerals develop and be changed during weathering and soil forming processes. They take effect on soil properties in a close relationship with each other. Our experiences on soil properties and soil behavior connected to mineral fraction are summarized in Table 1. Minerals in the soils of Hungary are known from the national clay mineral mapping survey that lasted 12 years and these data were amplified by the results of smaller scale surveys carried out by other authors.{Stefanovits & Dombóvári, 1985) 500 profiles were examined during the mapping program. The profiles were chosen based on the characteristic places shown on soil maps. The samples were examined by semi quantitative X-ray diffraction method in cooperation with experts in the Central Chemistry Research Institute of the Hungárián Academy of Sciences. Both the entire soil material and the clay fraction were tested with X-ray method. Further information about the mineral fraction was collected from the results of chemical, thermic and