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In the years 1983 and 1984 inventory of Tawny Owl territories by the mapping method (Domaszewicz et al. 1984a), using vocal stimulation, was carried out on an area of 240 km² (areas Al and A2 in Fig. 1). Additionally data concerning occurrence of Strix aluco on area of 50 km² was obtained from other observers. Wooded areas comprised 7-10%, and built-up areas 50-60% of the total. In the central part of the city (Al = 100 km²) built-up areas covered 70-80%. Census results, literature data and that obtained from informers (Table 1) indicate, that the Tawny Owl was recorded to be permanently in 12 green areas during the last 20-30 years. It disappeared from 9 territories and was found in 19 others, where it was not recorded earlier. During the study period 26-31 pairs (Fig. 1) were recorded within the study area of 290 km² (l pair/10 km²). In the central zone Al the density was 1.2-1.6 pairs/10 km². The total number of population of Strix aluco in Warsaw (485 km²) was estimated to be 40-60 pairs. The data obtained concerning productivity of broods (x̅ = 3.1 juv. per successfull brood) confirm Wenland’s results (1980) who indicated the high number of offsprings of this species brought up in urban conditions.
Tho diet of Tawny Owl as a function of urbanization was studied in Central Poland in 1976-1984. The pellets were collected from 24 sites in habitats along an urbanization gradient ranging from the large, relatively undisturbed Kampinos Forest (1441 prey items), through small woodlots surrounding Warsaw (686) and into the city of Warsaw (2567). Diet varied due to urbanization: the proportions of mammals and amphibians were lowest in the city center (respectively 11.3% and 0%), but the proportion of birds, largely House Sparrow Passer domesticus increased from 2.9% in the forest to 88.7% in the city. Niche breadth and seasonal variation declined with urbanization. Relationships between diet composition and habitat structure of owl's hunting range in the city, as well as on the seasonal diet variation from owls hunting in forests, let to conclude that the owls were able to exploit locally abundant prey from a variety of habitats. Although the highest densities of Field Mouse Apodemus agrarius were noted in parks and cemeteries, our data suggest that Tawny Owls catch this species more effectively in small gardens and secondary growth areas. The predation on Field Mouse by a pair of owls breeding in an urban cemetery was low. Approximately 3.2% of the population were removed by the owl predation, considerably less than in a more rural population.
Since 2008, it has been recognised by most health authorities worldwide that the abuse of newly-emerging psychoactive drugs, (‘designer drugs’/‘legal highs’; DD), in youth is a rapidly increasing problem, especially in the EU, threatening to offset gains made in tackling established and illegal drugs which they are intended to mimic; DD diversity is continually increasing to circumvent laws. The aim of the study was to determine the scale of DD abuse/availability amongst Polish youth. The surveyed test population was randomly selected from a representative group of adolescents attending high schools, secondary schools and universities throughout Poland. Questionnaires were completed by 14,511 subjects (10,083 school pupils and 4,428 students). Few persons from each group admitted using DDs; 453 schoolpupils (4.49%) vs. 81 students (1.83%). More males (4.74%) took DDs than females (2.77%). The tendency to take DDs in the company of friends was high in both DD-taking groups (>80%). DDs were consumed mostly in open spaces (34.15%), discos/pubs (21.13%) and boarding school/friend’s house (20.57). Most frequently, DDs came from shops (57.68%), friends (31.46%) or dealers (10.11%). Ensuing symptoms included; happy/euphoric mood (58.80%), talkativeness (42.51%) and hallucinations (22.85%). Over 74% of DDtakers in both groups experienced adverse reactions, and those requiring help sought it from: friends/colleagues (6.74%), doctors (5.06%), and hospitals (4.87%), but most rarely from parents/guardians (2.62%). Urgent action is being taken, especially in youth education, to prevent DDs becoming the serious menace seen with conventional drugs.
Differences between modern pollen rains in three types of phytocoenoses were studied in two regions, i.e. Tuchola Forest and Toruń Basin. The phytocoenoses in question were heaths, young pine-birch growths and mature pine tree stands, which form a temporal sequence and spatial mosaic in the landscape. In order to compare the structure of pollen samples, phytocoenoses and the landscape, the methods of numerical taxonomy were applied. An increase in the average number of sporomorphs was recorded, as well as in the taxonomic diversity of the pollen spectrum in this temporal sequence arranged from non-forest communities through young growths to mature forests. In the subsequent developmental stages, also the percentage contribution of Pinus pollen increased, as well as the total contribution of arboreal pollen (AP). The increase in the percentage contribution of arboreal pollen is accompanied by the decrease in the contribution of non-arboreal pollen (NAP), including Calluna and Ericaceae. Also a small increase in the number of species was observed. With the increased pine domination, however, the diversity of pollen types (expressed by rarefaction and Shannon-Wiener indices) decreases. As a result of the performed analyses, it was also found that the species composition of phytocoenoses and a pollen spectrum differs considerably, because the import of pollen from further areas exerts a significant influence on the structure of a palynological sample. The genus Calluna is the only type of plants characterized by a strong relationship between the occurrence in a phytocoenosis and in a surface pollen sample. Similarity between the taxa composition of a pollen spectrum and the landscape structure, consisting of a mosaic of phytocoenoses, seems to be higher than between a pollen sample and a phytocoenosis from which that sample was collected. The latter thesis, however, needs to be confirmed by further researches.
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