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The aim of the research conducted near the Płock Mazovian Refinery and Petrochemical Plant was to elaborate the methods of identification changes in natural environment affected by such large industrial enterprise. The solution of the problem was reached by comparison two basic components: volume of input to the ground of selected elements emitted by the Petrochemical Plant and the resistance of natural environment to the pollutants. The volume and spatial diffusion of these elements were searched through the chcmical analysis of snow cover. Resistance of the natural environment to the compounds studied was determined on the basis of six traits responsible - among others - for shaping the environment.
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The breeding avifauna was studied in the years 1983-1985 in 17 Warsaw parks, 185 ha in total area. The location of the areas in the city has been presented in Fig. 1, and their characteristics in Tab. 1. The aim of the study was to determine changes in the breeding avifauna by comparison with the data from similar researches in the same areas, carried out in the mid-70s, and to establish the influence on the avifauna of the nest-boxes put up in the parks censused. Observations were carried out from the end of March to mid-Julay (5 to 15 in each park, depending on the park area size). Counting was based on the standard mapping method extended by the seeking of large-species nests and addition of data on nest-box breeding. During the three breeding seasons a total of 37 breeding species and 7 probable breeding species (Tab. 2) were recorded. The largest numbers (up to 31) of species were found in large parklands (above 15 ha) with old or medium-aged stands, and the smallest (8-9) in small parklands and parks with young tree-stands. In areas above 5 ha the numbers found ranged from 8 to 9 p/10 ha in „open", young-stand parks, up to 86-89 p/10 ha in old or medium-aged large parks. Data on the composition and long-term variation of the avifauna of the particular parks have been set out in Tabs. 3-5. The amplitude of short-term variations in the composition of the parks studied (Tab. 6) was not big enough (Renkonen's coefficient exceeded 60%) to significantly affect the representativeness of the picture obtained from at least two years' data. It was also possible to define the long-term changes that had taken place since the 1970s. An increase was found of the number of nesting species, on an average by 3-4 in each park. The largest numbers of new species were recorded in young-stand parks. The avifauna was also found to have increased its numbers (on an average by 13-22 p/10 ha/park), mainly due to the use of nest-boxes. The long-term changes listed in Tab. 7 had been caused by the following factors: permanent changes made in the study areas (without using nest- boxes), use of nest-boxes, intensified synurbization of some species. Vegetation changes (most intensive in young-stand parks) and other changes, brought about by man's activity, caused the following species to disappear from the study areas: Perdix perdix, Acrocephalus palustris, Alauda arvensis, Galerida cristata, Motacilla flava, Motacilla alba, Luscinia luscinia, Phylloscopus trochilus, Lanins collurio, Cuculus canorus. Cleaning and barring of large tree-trunk holes in old parks was the cause of a considerable decrease in numbers of Corvus monedula and Sturnus vulgaris in that habitat. Though the area overgrown with bushes had decreased, and the litter layer had been destroyed, no changes could be seen in the numbers of: Hippolais icterina, Erithacus rubecula, Phylloscopus collybita, Phylloscopus sibilatrix, Sylvia atricapilla, Sylvia communis, Sylvia curruca, and the species even sometimes settled in new territories. In most parks there occured a growth in numbers of species nesting in tree tops: Pica pica, Corvus corone, Streptopelia decaocto, sometimes Oriolus oriolus and Columba palumbus. In the years 1983-1985 a total of 750 nest-boxes were put up in the parks censused (Tab. 1). The effect of this practice on the composition of the avifauna was assessed (Tab. 8) on the basis of data for the 1970's, when there were not nest-boxes there. The putting up of nest-boxes had a direct influence by causing an increase in the level of numbers of the avifauna (particularly in new parks). Nest-boxes resulted in the settlement or increase in numbers of the following species: Passer domesticus, Sturnus vulgaris, Parus caeruleus, Ficedula hypoleuca and Passer montanus. The use of nest-boxes has not been found to have a direct influence on the number of those species that do not nest in tree holes. In comparison with tire 1970s, a clear growth was found of synurbized populations of six species, particularly: Turdus pilaris, Turdus merula, Pica pica, Corvus corone, as well as Columba palumbus and Coccothraustes coccothraustes. The process of synurbization of Garrulus glandarius and Turdus philomelos was found to have started, while Anas platyrhynchos and Streptopelia decaocto were found to have increased their numbers.
Badano właściwości reologiczne ziarna pszenic krajowych Ostka Popularna i Nagradowicka oraz kanadyjskiej Amber Durum przy użyciu konsystometru Hoepplera. Pojedyncze ziarna pszenicy poddawane były jednoosiowym obciążeniom statycznym. Ziarno obciążone w dwu kierunkach, a mianowicie wzdłuż dłuższej osi ziarna oraz w kierunku poprzecznym (ziarno leżące na bruzdce). W pracy niniejszej podczas badania właściwości reologicznych ziarna poddawano je próbom: pełzania, polegającym na szybkim obciążeniu badanej próbki i obserwacji odkształcenia względnego w funkcji czasu.
Magpie in Warsaw is sedentary and ubiquitous species inhabiting all types of urban habitats. This study (1986-1990) estimated the breeding population in the entire area of Warsaw (485km²) at 6-8 p./km², and in winter (on the area of plots 245km²) — at 11-17 ind./km². The frequency of distribution in both seasons was 92-93% in the whole area 92-93%, and 100% in the inner city plots. Density in the inner city (52km² —19 p./km², in winter — 29 ind./km²) was 3 times higher than in the outer urban zone (150km² — 7 p./km², in winter 54km² 11 ind./km²) and 4-5 times higher than in outskirts (283km² — 5 p./km², in winter 139km² — 6 ind./km²). Density of population in winter decreased on outskirts and increased in inner city areas. The highest abundance was in green riverside belt (24 p. and 38 wintering ind./km²), in housing estates (21-25 p., 32 ind./km²) and in city parks (20-23 p., 36-37 ind./km²). The lowest was in peripheral forest parks and agriculture areas (2-4 p., 4-7 ind./km²). Colonization of the inner Warsaw by Magpie began in 1950-ties. Since then its population in this area (52km²) increased from few pairs to 800-1200 pairs. It reached the position of subdominant in the bird community, and its success is probably most dynamic among all species of the avifauna of Warsaw.
The basis of the work was data on changes in avifauna in the years 1984-1994, obtained by way of a questionnaire of 32 authors from 15 cities in European Russia and 4 in the east of Poland. The results of the survey were burdened by subjective errors, but did nevertheless indicate significant dynamics to the changes in the avifaunas of the cities studied. The survey revealed a trend towards increase and the occupation of new cities among 23 species. The trend was clear in the whole area for Anas platyrhynchos, Pica pica and Corvus corone cornix. Declining trends were shown for 10 species — with the most universal being those for Hirundo rustica and Sturnus vulgaris, and in the cities of Russia also for Delichon urbica. For 22 species, the questionnaire indicated a considerable degree of stabilization of the situation, or else a lack of regularity in the direction and distribution of changes. Comparison with a similar survey carried out in the years 1983-1984 in 27 Central and Eastern European cites showed similar trends for 13 species and reverse trends for 2 (Sturnus vulgaris and Delichon urbica).
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