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Too intensive management by mowing or grazing or cessation of management both lead to the floristic impoverishment of meadow communities. Soil seed bank can play an essential role in the ecological restoration of species-rich semi-natural grasslands. In Poland, little research has been conducted in this area, particularly refers to Arrhenatherion meadows. The aim of the studies was to determine the density and species composition of the soil seed bank of Arrhenatheretum elatioris meadows as well as the distribution of seeds across four soil levels. The studies were carried out in two habitats: Arrhenatheretum elatioris (code 6510-1) and Poa pratensis – Festuca rubra (code 6510-2). Soil samples were collected up to a depth of 20 cm, divided into four levels: 0-5 cm, 5-10 cm, 10-15 cm 15-20 cm. The size and species composition of the seed bank was determined by extracting seeds from the soil samples. The number of diaspores (seeds and fruits) in the topsoil (0-20 cm) layer was 56,430 seeds·mˉ² (Arrhenatheretum elatioris) and 118,510 seeds·mˉ² (Poa pratensis – Festuca rubra). The soil seed banks were dominated by diaspores of annual dicotyledonous species (above 80%) which were mainly seeds of arable weeds or ruderal plants. The assessed soil seed banks were dominated by Chenopodium album and Stellaria media. In both grasslands, the quantity of Poaceae and Fabaceae diaspores were very low. These results confirmed that most mesic grassland species did not form persistent seed banks and reintroduction of target species seeds is necessary in order to restore the species-rich Arrhenatherion elatioris meadows.
Przedstawiono wyniki prac prezentowanych na sympozjum w Graz (Austria) w 1991 r. Omówiono zasady ochrony i poprawy zdegradowanej runi, kontrolę zachwaszczenia przy użyciu metod biologicznych, mechanicznych i chemicznych, renowację użytków zielonych przez podsiew i przez zasiew.
The aim of the studies was estimation usefulness of Arrhenatherum elatius and Lolium perenne for renovation by reseeding of moderately dry meadows. Estimation of some of biological features of those species such as: rate of emergence and tillering, development of above ground and underground biomasses, tillering intensity, vertical distribution of above ground biomass in the yields and ability to remain after reseeding was done. Three series of studies were carried out: pot experiments out in vegetative hall of Institute of Land Reclamation and Grassland Farming in Falenty; field experiments: pure stands and reseeding of degraded meadow after two times cultivation of the old sward using single species and mixture. Field experiments were carried out in experimental station of SGGW Grassland Department in Jaktorów, in the natural moderately dry meadow site. Cv. Wiwena of Arrhenatherum elatius and cv. Argona of Lolium perenne were studied. Two dates of sowing: spring and late-summer were using. It was found that cv. Wiwena of Arrhenatherum elatius and cv. Argona of Lolium perenne were suitable for reseeding of moderately dry meadows. They had fast growth and development rates after sowing. Arrhenatherum elatius has ability to good remains in the following years after reseeding. Lolium perenne is characterized by great competition only in the first year after reseeding whereas its persistence is not good enough in the following years. Moreover it was found that spring term was better for reseeding of moderately dry meadows. It guarantees better development of plant biomasses both above ground and underground. Irrespective of sowing date proper soil moisture is favourable to plant development and it is support to achieve success of reseeding.
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