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Based on results of the bryofloristic investigations carried out in 2006 along tourist roads and around mountain chalets the problem of bryophyte response to the tourist utilization of the summit region of Karkonosze Mts is discussed here. The hypothesis that introduction of cement as building material might have caused the income and spread of subneutral or basiphilous ruderal species in that naturally acidic region was formulated and tested. In result 45 species were found, of which the majority do not occur in natural sites in the Karkonosze Mts. Among them 20 species are convinced to be highly hemerophilous. Most of the found species were eurytopic, only 14 prefered subneutral or basic substrata. Many of them produced sporogonia, what indicates high reproduction potential. It seems that the phenomenon of synanthropisation is limited mainly to places in which cement (as mortar or concrete) has been used. The list of bryophytes found around all the anthropogenic sites and along the tourist roads in the summit region of Polish part of the massif with brief characteristics of their ecological preferences has been included.
The object of the studies presented in this paper was the flora of field plantings of different origin. The vascular flora of the plantings examined comprises 254 taxons. including 53 trees and shrubs, and 201 herbaceous vascular plants. The flora is rich and diverse. In 26.8% of taxons it is presents in all types of plantings. More than half of the registered species occurs once or twice only in all 23 planting groups studied. A detailed analysis of the flora examined shows that field plantings in agricultural landscapes may, in a small number of cases, constitute a source of weeds diaspores propagating in fields.
Geobotanical studies conducted in spring in 2011–2012 in the Zagórów polder washland, covered by the ecological restoration programme, provided assessment of current nature value of plant communities and indicated potential directions of their further transformations as a result of changes in habitat water content levels. Based on the analyses of 77 relevés of 50–100 m2 each, prepared following the Braun-Blanquet method, water levels were assessed by phytoindication using moisture indicator values (F) according to Ellenberg et al. (1992). Moreover, nature value of vegetation was assessed based on the botanical structure, geo-historical spectrum, life form structure as well as the nature valuation index in the 10-point scale according to Oświt (2000). Based on relevés the area was valuated using the point score method according to Mahon & Miller (2003). An attempt was made to indicate potential directions of changes in vegetation, based on the determination of dependencies between certain parameters assessing its current condition and habitat conditions. Habitat water content connected with the supply of water through a network of culverts, geomorphology of the area and land use, affects the distribution of phytocenoses in the polder and their considerable diversity, which was confirmed by the identification of 19 plant communities from six phytosociological classes. Further maintenance of water relations and land use results in the transformation of plant communities: in the vicinity of culverts – towards the class Phragmitetea, in swamps and around small water bodies – towards communities of the classes Salicetea purpurea or Alnetea glutinosae, at longer distances from culverts in leveled and agriculturally utilised areas – towards the orders Trifolio fragiferae-Agrostietalia stoloniferae and Molinietalia, while in areas at valley margins the succession progresses towards communities of the class Nardo-Callunetea.
The paper discusses the methodical problems encountered when making up the list of archaeophytes appearing in Poland. The updated list of archaeophytes (Tab.1) including data on their appearance in archaeological excavations according to the Archaeobotanical Data Base (Lityńska-Zając unpublished) has been attached as one of the principal parts of the paper.
This paper aims to verify the hypothesis that magpies in urban environments favour poplars as nesting trees, as suggested by previous authors. The fieldwork was conducted in a 180 ha area in a district of Gdańsk (North Poland). The study area held 5294 trees and high shrubs, where 124 magpie nests were found in 10 species of trees. Results of log-linear analysis showed that the magpies chose particular tree species rather than types of spatial tree organization. The lombardy poplar (Populus nigra “Italica”) is the species most frequently chosen as a nest tree, however – the magpies showed a significant preference for trees growing separately or in pairs. The choice index (the ratio of expected to observed frequency) confirmed the magpies’ strong preference for black poplar cultivars and for birches, regardless of the trees’ grouping. The magpies preferred lombardy poplar when they had the choice of two poplar cultivars. This cultivar has a crown suitable for the magpie’s nest construction because of the small angle between the trunk and the branches. The thin, almost vertical branches probably also limit predators from penetrating the crown because these branches do not provide much support for tree climbers. The large-scale planting of lombardy poplars in Polish towns in the 1960s and 1970s has probably contributed to the significant increase of the magpie population in the urban environment.
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