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We conducted this study in Naples, Italy from 1990-93. We inventoried birds and habitat types in each 1km² block of the UTM grid covering the entire city. We found a positive correlation between the number of species and the number of habitat types within the UTM blocks. The highest number of species occurred in blocks with the largest woodland areas. We also considered the variation over the study area in number of species among habitat types. We formed an urbanization gradient for habitat types based on the density of buildings and size and type of the green area. We calculated the frequency of each species (expressed in %) in relation to the urbanization gradient for every habitat type. We found that the most synanthropic species were: Columba livia dom., Turdus merula, Passer italiae, Serinus serinus. We used multivariate statistical analysis based on frequencies (in %) and presence/absence of species to classify the habitat types. The arrangement based on percent frequencies was in accord with the urbanization gradient from the suburban woodlands to the built-up areas.
The increasing interest in the urban ecosystem is indicated in Italy by the great number of ornithological atlases in progress. Since 1986, research has been carried out in 14 urban areas ranging in size from 10-360 km². Seven of these have already been published. Atlases of the wintering bird community are being prepared in two cities and an atlas of the entire annual bird fauna has been completed in another city. Since 1990, a coordinating group has been meeting to standardize research methodologies, and to exchange results and information. A classification of the environments occurring in Italian cities has also been drawn up. All the urban atlases produced in Italy thus far have been based on small-sized mapping units (0.25- 2.00 km²). In some cities, quantitative survey methods, such as extensive mapping, transect, direct counting, VCP, have also been used. In Italian urban areas 167 species of birds have been recorded thus far (47.6 % of the Italian avifauna). The main aims of an urban ornithological atlas are scientific (faunal), practical (urban planning, nature conservation) and cultural (education). The research carried out to date will make it possible to draw a picture of the Italian urban bird fauna. Moreover, a comparison of historical and present records may allow future trends to be foreseen.
Acta Ornithologica
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1996
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tom 31
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nr 1
81-84
A breeding bird atlas was constructed for Berlin (West) based on field work conducted in 1977-1983 and repeated in 1989-1991. Surveys were performed within an area of 9000 ha. using a grid size of approximately 100ha. Species turnover-rates for the 90 plots averaged 22.8 % ±6 % and was generally similar among all habitat types studied (block buildings, high-rise buildings, industrial zone, residential area, parks/cemeteries). However, mean number of species per plot increased in the same order as habitats from 18.1 ±4.1 up to 32.2 ±4.6. The change of a farmland plot to a reconstructed park resulted in a nearly 50% change in species composition. Species dispersal and plot turnover-rates were analyzed in relation to patterns in plot occupancy; resident species and short-distance migrants tended to show a greater positive relationship to distributional pattem than long-distance migrants. A striking exception to this relationship occurred with the Crested Lark Galerida cristata where the relationship broke down for the Berlin population. A similar situation developed in other parts of Central Europe. But the Song Thrush Turdus philomelos, a short-distance migrant, suffered differential losses in the urban environment as related to the stability of surrounding forests.
This paper presents results from the two years of field studies (winters and breeding seasons 1993-95). The work include the entire municipal area (116.5 km²) of Lvov (0.8 million inhabitants). The study area was subdivided according to biotops forming an irregular mosaic. Based on 14 biotops, 105 plots of varying size were delineated. The winter inventory consisted of one survey conducted in each of 105 study plots. A total of 58 bird species were recorded; 34 of these had populations densities above 1900 individuals/km². Species with the highest densities included the House Sparrow Passer domesticus (830 individuals/km²), the Rook Corvus frugilegus (490) and the Feral Pigeon Columba livia dom. (190). During the 1994 and 1995 breeding seasons the survey included an area of 66.5 km² of the city. Three census visits were conducted in each study plot. 71 species were recorded, with the House Sparrow and the Feral Pigeon most numerous. Of particular interest was finding that the Raven Corvus corax, Redstart P. phoenicurus and Willow Warbler Phylloscopus trochilus — were breeding in the central part of the city.
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