Changes of Grassland Vegetation in Surroundings of New Railway Flyover (Eastern Bohemia, Czech Republic). Part I: Plant Communities and Permanent Habitat Plots

Abstract

Paper shows (1) the results based on vegetation mo nitoring during the time period 19752005 in the grassland segment of undulated landscape alo ng railway corridor close to village Dlouha T řebova (Usti nad Orlici district, Eastern Bohemia, C zech Republic). Survey was focused on the meadow communities, identification of phycenological changes by comparison of historical phytosociological recor ds (1975) with the present ones (2005). (2) Actual releves taken within transect design sho wed that there is direct dependence between the meadow species composition and soil moisture gradient. Along the soil moisture gradient different formations can be found : Carex acuta communities occupying the wet sites close to river bank with high groundw ater table, followed by wet Calthion meadows with Cirsium rivulare in mosaic with Holcus lanatus formation on drier microsites. Arrhenatherum elatius stands grow in mesic conditions in contact with Calthion wet meadows. Dry sites on high slope are dominated by Festuca rubra . There are also some plant species of semi-thermophilous flora and species that prefer more acid soil reaction as a part of grassland complex. Meadow bio topes which were not affected by site alteration during bridge building, and communities with Carex acuta seem to be relatively stable in time. There are two populations of protec ted rare plant species in the locality: first an orchid Dactylorhiza majalis and the second Gentianopsis ciliata . (3) The railway reconstruction resulted mainly into degradation pro cesses of grassland sites which is documented by the sown plant mixture or ruderal pla nt assemblages.