Initiierte Entwicklung von Sandtrockenrasen im Tagebaugebiet "Goitsche" bei Delitzsch

Abstract

In vegetation free embankment locations of the post coal mining pit "Restloch Holzweißig-West" in theCentrat German coal mining district "Goitsche" (Federal Republic ofGermany, states Saxonia and SaxoniaAnhalt)experimental sites for transplantation and sowing were installed and observed in 1993-1995. Byusing different methods ofvegetation initialization (transplantation of grass sods, plantation and sowing)we tried to facilitate the establishment of autochthonaus species of comparable undisturbed habitats (drysandy grassland). By means ofvarying the initial density, the species composition, the substrate characters,and the slope of embankment basic Information about an accelerated, quasi-natural vegetation developmentwas aquired. The experiments illustrate the establishment behaviour ofthe species studiedunder differentbiotic and abiotic conditions. By means of seed rain traps the dispersal potential of species ofthe surroundingarea was determined and their establishment behaviour in the experimental sites as weil as in control sites isdiscussed.Within the experimental sites of grass sods the dominant proportion of some species changed. Especiallyspecies with high generative or vegetative expansion ability (for example Corynephorus canescens andHieracium pilosella) colonized the intersites already in the frrst year.Populations initiated by sowing or plantation need a Ionger period for their development since the stage ofmaturity is not reached by most species before the second year.The experiments show that the establishment of psammophytic grassland is only possible within certainIimits ofhabitat conditions. As a result of investigation we conclude that it seems to be useful to combinedifferent methods of vegetation initialization. One preferred possibility is the exhaustive sowing ofCorynephorus canescens, supplemented by transplantation of grass sods and plantation of selected species.