Various phytosociological plant communities may develop on fallowed arable lands depending on soil-and-climatic and topographic conditions. In this paper the Authors have presented conditions under which xerothermic vegetation encroaches on arable lands. Characteristics of fallowed arable lands, which during the diversified in time process of self-sodding changed into xerothermic communities of sward type, was presented on the basis of phytosociological characteristics of selected fallowed arable lands situated in the vicinity of Pińczów and Staszów. It was found, that depending on the substratum, plant communities belonging to various phytosociological units develop on the fallowed arable lands. Communities forming automatically in the initial period of fallowing are characterized by a considerable degree of fortuity. The course of plant succession on fallowed arable lands situated in soil-and-climatic zones favouring xerothermic vegetation advances a development of steppe plant communities through a process of self-sodding. Depending on the geological substratum (gypsums, marls or limestone) and also on the thickness of soil deposit they are diversified in respect of their phystosiociology. ...
Xerothermic swards occurring in Poland are extremely valuable communities because owing to the presence in them of plant species originating from warmer climatic zones they increase the biodiversity of domestic grass ecosystems. They also contribute to improvement of landscape amenities in the areas where they occur. The Malopolska Upland is a region where xerothermic swards are quite numerous. Generally they cover small areas, usually on sites where warm and dry habitats are found, mainly on strongly sun-heated slopes with southern aspect. Four plant alliances are present in the xerothermic swards on the Malopolska Upland Sisymbrio-Stipetum capillatae alliance can be encountered on gypsum rocks 129 covered with thin layer of loess soil. Another alliance forming on gypsum substratum covered with slightly thicker loess layer is Thalictro-Salvietum pratensis assemblage. The alliance frequently found on the Malopolska Upland is Inuletum ensifoliae covering the southern steep slopes of the terrain elevations developed from senonian marles. The fourth alliance of xerothermic vegetation commonly present on the Malopolska Upland is Adonido-Brachypodieto pinnati plant assemblage, encountered on deeper loamy-clay or humus brown soils similar to chernozems. Xerothermic swards, which are not climatic assemblages undergo a natural plant succession, changing into forest ecosystems. Therefore, human interference is crucial ...
