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Abstrakt

In this study the effect of different grassland managements (cattle grazing with different intensities and mowing) on soil mesofauna, i.e. mites (Acari) and springtails (Collembola), was studied. Mites and springtails are the most numerous representatives of soil mesofauna organisms living in the upper soil layers (up to 5 cm). Soil mesofauna groups or species are commonly used as bioindicators of soil health. The experiment was carried out from 2007 to 2009 in the West Sudety Mountains, Poland. Pastures and meadows were under organic farming management, without pesticides or synthetic fertilizers, and restricted livestock density. Soil samples were taken three times a year (in May−June, July and October) from pastures grazed at different frequencies: once, twice and four times a year, alternate management (grazed and mown pasture) and mown meadow. Mites were identified according to orders or suborders (Oribatida, Gamasida, Prostigmata, Astigmata), while springtails to the species level. The data were analysed using a general linear model (GLM). The mesofauna taxa in relation to the treatment and date were analysed with the canonical correspondence analysis (CCA). The data from three years showed that most soil mesofauna assemblages occurred in significantly higher numbers on the pasture grazed once or twice and on alternate managed pasture than in pasture grazed four times a year and mown meadow. The CCA analysis showed the preference of most springtail species to pasture grazed once a year, while mites preferred pasture grazed twice a year and alternate management. The number of species and the abundance of the most numerous species (Protaphorura pannonica, Desoria multisetis and Folsomides parvulus) did not differ significantly between treatments. To summarize, cattle grazing once or twice a season or alternate management (grazing and mowing once a season) have a positive impact on soil mesofauna.
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Abstrakt

The aim of this study was to determine the ecological characteristics of vascular plants colonizing serpentine mining waste dumps and quarries in Lower Silesia. The investigated flora was analyzed with regard to species composition, geographical-historical status, life forms, as well as selected ecological factors, such as light and trophic preferences, soil moisture and reaction, value of resistance to increased heavy metals content in the soil, seed dispersal modes and occurrence of mycorrhiza. There were 113 species of vascular plants, belonging to 28 families, found on seven sites in the study. The most numerous families were Asteraceae, Poaceae, Fabaceae and Caryophyllaceae. Only 13% of all plants recorded occurred on at least five of the study sites. The most numerous were species related to dry grassland communities, particularly of the Festuco-Brometea class, which included taxa endangered in the region of Lower Silesia: Avenula pratensis, Salvia pratensis, Festuca valesiaca. Apophytes dominated in the flora of the investigated communities. Hemicryptophytes were the most numerous group and therophytes were also abundant. The serpentine mining waste dumps and querries hosted heliophilous species which prefer mesic or dry habitats moderately poor in nutrients, featuring neutral soil reaction. On two study sites 30% of the flora composition consisted of species that tolerate an increased content of heavy metals in the soil. Anemochoric species were the most numerous with regard to types of seed dispersal. Species with an arbuscular type of mycorrhiza were definitely dominant in the flora of all the study sites, however, the number of nonmycorrhizal species was also relatively high. It was suggested that both the specific characteristics of the habitats from serpentine mining and the vegetation of adjacent areas had a major impact on the flora composition of the communities in the investigated sites.
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