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The paper presents the floristic changes in species composition of meadow sward after five years when the meadows were desisted from management (cutting). The meadows are situated on hydrogenic soils in proglacial stream Valley of Vistula River and they belong to landscape reservation "Ursynów Slope". In 1998 before the first cut vegetation patches were separated according to floristic aspects. Then samples of vegetation (from 1 m² ) were taken from cach patch; number of samples depended on floristic diversity and ranged from 1 to 4. Floristic types were determined basing on the dominant species with the share above 30% of mass. In 2003 the samples of vegetation were taken from the same places and using the same methods like in 1998. The floristic changes in species composition of meadow sward after desistance from management for five years resulted in: decrcasing in the total number of species - from 78 (1998) to 66 (2003); disappeared mainly the species from dicotyledons (8 species), among them very low species and ephemeral weeds, decrcasing in the number of floristic types - from 16 (1998) to 9 (2003), increasing in the sward of poor quality grasses such as Deschampsia caespitosa and Holcus lanatus. Those species became dominant in three of floristic types and their share exceeds more than 30% in the majority of meadow sward, increasing in the share of high grass species and decreasing in the share of low grass species, the great increase in the share of sedges, rushes and horsetails in 2003, the great decrease in the share of dicotylcdons (weeds and herbs) in cach floristic type, invasion and expansion of weeds of areable lands, later development of trees and shrubs and increasing in the share of forest species in the meadow sward. Preservation of existing biodiversity is possible only in case of introduction of active preservation using extensive form of management.
The aim of the analysis conducted on the street lawns in Warsaw was to specify the share of grasses in the sward. Floristic research was conducted by means of phytosociological record method according to the Braun-Blanquet's school and it analysed plant cover. Furthermore, the research compares grasses share in sward depended on soil salinity. According to research from 1999-2001 the street lawns comprised of 80 species, out of which 16 were grass species. External belts of street lawn sward comprised of 55 plant species, with 12 grass taxa. Internal belts of street lawns comprised of 61 plant species, out of which 14 were grass species. The percentage of plants in middle belts of the street lawns reached 96% of plant cover and in side belts - about 70% of the plant cover. External belts of street lawns comprised from 24 to 33 dicotyledonous plants and 3 to 9 grass species. Grass species constituted 21.0-38.6% of street lawn's plant cover. The electrolitic conductivity reached from 0.8 to 1.2 mS cm⁻¹. Research compared individual species' share in lawn sward and it showed that, among grass species, Agropyron repens, Setaria pumila, Puccinellia distans, Festuca rubra and Bromus hordeaceus have the highest indices of plant cover. Internal belts of street lawns comprised from 20 to 29 dicotyledonous plants and 6 to 10 grass species. Grass species constituted 26.8-40.4% of street lawns' plant cover. The electrolitic conductivity reached from 0.3 to 0.45 mS cm⁻¹. Research compared individual species' share in lawn sward and it showed that, among grass species, Festuca rubra, Lolium perenne, Agropyron repen, Bromus hordeaceus and Dactylis glomerata have the highest indices of plant cover.
Fragmenta Faunistica
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1993
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tom 36
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nr 01
5-11
The paper discusses the major aims and the scope of studies of animal communities inhabiting pine forests in Poland. The studies were earned out by the Institute of Zoology of the Polish Academy of Sciences in the years 1986-1990. They are a continuation of a broader research programme concerned with the structure of fauna communities of the most common habitat types in Poland, including both natural habitats and those transformed by man.
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