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The studies of fallow lands were undertaken on the Przemyśl hills in the area of Cisowa locality which, till very recently, have been owned by a State Farm (PGR). The objective was to gain insight into the composition and diversification of plant communities on meadows, pastures and fields laid fallow, in context of habitat conditions prevailing after the use had ceased. The study utilised an old cadastral map showing the type of communities by category of use: meadows, pasture, and cultivated fields. The study material consisted of 180 relevés, obtained in the period 1998-2000 using the Braun-Blanquet method. By employing numerical classification, eight plant communities were distinguished, including only two of the association rank: Epilobio-Juncetum effusi, Arrhenatheretum elatioris. The analysis of Ellenberg’s habitat indices proved that all the communities belonged to the half-light vegetation group, occurring mostly on fresh soils, under intermediate moisture-content conditions, more rarely on moist soils which do not dry out. The soil reaction was most often neutral or slightly acidic, and in most of the soils the nitrogen content was in the intermediate range. The two principal trends in the succession of communities in the area, after its farming management has ceased, are: marked increase in species richness resulting from the expansion of species, and the process of overgrowing by woody vegetation.
The investigations of meadow and pasture fallows in Czyrnianka catchment area, during vegetative season of year 2002, were carried out. The purposes of these investigations were qualifications of plant communities, characterisation of their habitat conditions and making habitats for constant protection. 53 phytosociological relevés by classic Braun-Blanquet method were performed and taken under numerical classification. As a result of classification the types of Gladiolo-Agrostietum and Epilobio-Juncetum associations and Cirsium arvense-Agropyron repens community were originated. For characterisation of habitat conditions the indicator values by Ellenberg were used. The Detrendent Correspondence Analysis showed that moisture was responsible for differentiation of community composition. A dry variant Gladiolo-Agrostetum association, which contains species characteristic for xerothermical grasslands, is the most interesting from botanical point of view. This community is also protection worth.
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