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Obiektem badań jest osiedle robotników leśnych Asmus w Borach Tucholskich. Stan obserwowany i stan teoretyczny różnią się - z ekologicznego punktu widzenia - wieloma cechami. Rozwój zrównoważony systemu jest opisany przez wskaźnik „ascendencji całkowitej" i „ascendencji wewnętrznej".
Spatial distribution of heathlands in Pomerania (the north-western part of Poland) was described based on the results of questionnaires sent out to the registered offices of all forest divisions (96), national (4) and landscape (15) parks of this area. According to the inventory, heathlands occur in 28 forest divisions and 3 national and landscape parks. The frequency of occurrence and the area covered by heathlands were determined. All the data were compiled in the form of a spatial database with the use of Geographic Information Systems. The paper also contains the geographical distribution of heath habitats in the area of Pomerania according to particular syntaxa. Additionally, the content of the database CORINE Land Cover was analysed at the third level for the area of Pomerania, completed for the years of 2000 and 2006. The area and the number of patches were described according to three land cover categories: heaths (code 322), conflagration sites (code 334) and peat bogs (code 412).
The paper describes changes in the distribution and the surface area of heaths during the last, nearly 120 years at two research sites located in the city of Toruń. The first site "JAR" is a former land of military manoeuvres in the northern part of the city, where a unit of the Soviet Army had been stationed after the 2nd World War till 1991. The second site "Glinki", situated at the south-western end of the city, was also exploited as a military land. During the 2nd World War, a German prisoner-of-war camp was located here, and after the war some industrial plants were built and allotment gardens were established, whereas part of the area was treated as a wasteland. The history of both areas and the vegetation changes were reconstructed from the series of temporal topographic maps and aerial photos, as well as a high-resolution Ikonos satellite image. The aforementioned source materials were analysed with the technology of Geographical Information Systems, applying the software Arc-GIS ArcView 9.3. For both sites, the range was determined, as well as the number of patches with common heather and the total area of heaths in particular years of land cover and land use mapping. The present state of heaths was defined based on the direct field exploration carried out with the use of GPS navigational devices. It was found that at present 22 heather patches occur at the site JAR, with the total area of11.7328 ha. Within the Glinki district, also 22 heather patches occur with the total area of 3.5701 ha. And thus, these are the largest sites of heaths located within the administrative boundaries of Toruń. Data collected through the field exploration of the site JAR were superimposed on the spatial development plan of the future housing estate. At an intersection of both information layers, fragments of the area were outlined where heaths can be preserved after the construction of a housing estate is completed. Their area is small. In the area of the Glinki district, the rate of expansion of industrial areas was determined for the last several years, as well as future changes in the land use were discussed, which will arise due to a housing estate scheduled for building here. The aforementioned analyses enabled to evaluate the present developmental state of both research areas, as well as to determine the future of low shrub communities, which occur here and which constitute a type of an ecological system listed among the UE protected habitats. The obtained results increase our knowledge on heaths in Toruń, and at the same time - also in Poland and in Europe.
Badania prowadzono na naturalnych łąkach słonych: w dolinie rzeki Zgłowiączki na Kujawach, oraz k. Pyzdr w Wielkopolsce. Przyczyną zasolenia tych terenów jest ascenzja wód mineralnych, kontaktujących się z cechsztyńskimi strukturami solnymi, do poziomu wód gruntowych. Pomimo zróżnicowanego poziomu i rodzaju zasolenia gleb stwierdzono podobny skład gatunkowy halofitów i występowanie podobnych zespołów roślinności słonolubnej. Na obu badanych obiektach największą powierzchnię zajmowały słone łąki ze świbką morską i miecznikiem nadmorskim (Triglochino-Glaucetum maritimae). Zwykle były one użytkowane jako łąki kośne. Na terenach wyłączonych z użytkowania obserwowano zarastanie siedliska trzciną (Phragmites australis), które w efekcie prowadziło do obniżenia wartości użytkowej łąk. Udział trzciny pospolitej był tu 2-4-krotnie większy niż na powierzchniach koszonych. Szansą na zachowanie bogactwa gatunkowego i wartości użytkowej tych siedlisk jest wdrażanie do praktyki zaleceń, dotyczących ochrony solnisk śródlądowych, zawartych w Poradnikach ochrony siedlisk i gatunków NATURA 2000 [Herbich 2004].
This paper presents the variability within two heath associations, i.e. Pohlio-Callunetum and Arctostaphylo-Callunetum in the territory of Poland. The variability of the former syntaxon was determined based on 9 sets of published relevés, made in different regions of Poland. In the case of the latter syntaxon, there were 13 sets of relevés. The sets were being compared in respect of species composition assuming the degrees of species constancy as characteristics of the compared sets. The comparisons have been done with the classic phytosociological method according to Braun-Blanquet, as well as with numerical taxonomy methods using the software MVSP. In both cases, the subsets of relevés from the artillery range near the city of Toruń were clearly separated from the others. In the obtained dendrograms, relevés from the neighbourhood of Toruń, classified within the analysed subassociations formed separate clusters and their distance to other groups of relevés from the same association but from different regions of Poland was significant. Both in the case of the association Pohlio Callunetum and the association Arctostaphylo-Callunetum, sets of relevés from the Skwierzyna (coniferous) Forest in western Poland and from the Tuchola Forest in northern Poland were the most similar to relevés from the neighbourhood of Toruń.
The paper presents a comparison of modern pollen deposition in Tauber traps after one-year exposure at two research sites - Laska and Widno, located in the northern part of the Zaborski Landscape Park in the Pomerania Province (Northern Poland). The studied sites were circular in shape with a radius of 2 km and an area of 1256 ha each. They were characterised by similar contribution of forest and non-forest areas, as well as similar species composition and area covered by tree species. Both sites differed, however, in the location of traps in relation to forest areas and distribution of deciduous trees amid pine monocultures. At the former site, a Tauber trap was placed in the open field, i.e. in xerothermic meadow, in the western part of the Laska village. At the latter site, a trap was placed on the borderline between meadows of the Widno village and the surrounding forests. At the site of Laska, scattered deciduous trees occurred mostly in the form of small clusters amid extensive pine monocultures surrounding the village. Whereas at the site of Widno, deciduous tree species covered larger areas in the form of more fertile oak-hornbeam forests, beech forests and birch woods amid pine forests. The size of area covered by tree species and the amount of pollen deposition by these trees were positively correlated at both sites. In addition, the average annual pollen deposition was calculated for each site for seven most abundant tree species during the period of 1999-2010. By comparing the arithmetic means, it was found that the pollen deposition at the site of Widno is higher for most of the studied arboreal species compared with the site of Laska, but these differences are statistically significant only in the case of birch and hornbeam.
Phytosociological analysis of non-forest communities was carried out on one of the oldest and the biggest military training grounds in Europe, located near the city of Toruń, in central Poland. Heaths and psammophilous grasslands developed here as a result of deforestation of inland dunes in the valley of the Vistula River, as well as a result of destruction of soils and vegetation brought on by manoeuvres and artillery firings. They form a landscape mosaic with young self-seeding pines, mature pine forests and birch forests. Using the Braun-Blanquet method, 84 relevés were made in the areas dominated by dwarf shrubs and 32 relevés within psammophilous grasslands. Applying the classic phytosociological method, the following plant associations were distinguished in the first set of relevés: Pohlio-Callunetum and Arctostaphylo-Callunetum, as well as the community with Cytisus scoparius. Within the psammophilous grasslands, two associations were distinguished: Spergulo vernalis-Corynephoretum and Calamagrostietum epigeji. In this paper, the heterogeneity within associations and communities was presented together with descriptions of individual syntaxa, as well as dynamic and developmental relationships between the aforementioned were identified.
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