FALLOW AS A SUSTAINABLE APPROACH TO SMALL-AREA GRASSLAND MANAGEMENT WITH RESPECT TO THE BIODIVERSITY IN GRASSLANDS

摘要

This study is devoted to the determination of sustainable ways of increasing flora and insect diversity in meadows through the establishment of barren sites and fallows, which help many ephemeral plant species to reproduce from the soil seed bank. Artificially established barrens in the Podyji National Park (Czech Republic) are studied as one of the sustainable ways how to increase biodiversity in grasslands. Permanent plots in a) periodically disturbed barren site, b) plot with spontaneous succession and c) neighbouring managed meadow were established. We confirmed that barren sites help many plant species to reproduce from the soil seed bank and finish their life-cycles. The results of analyses of phytosociological releves show differences in boththe species composition and the number of species between nutrient-poor and nutrient-rich sites. Significant differences were also found among plots in different successional stages. From the point of view of nature conservation, no massive occurrence of invasive and expansive species was found. Species commonly found in cultivated landscapes, field margins and balks prevailed. We tested the optimal time for the duration of a fallow and it seems to be 3-5 years; after this old fallows should be renewed.