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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).
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The aim of the study was to determine the fungi causing dying out of one-year- old heather seedlings. Observations were carried out on: 'Amethyst', 'Annemarie', Colette’, 'Perestroika' and 'Reini'. The shoots revealing necrotic symptoms were plated on PDA medium. 25 species of fungi were isolated. Among them Pestalotia sydowiana, Alternaria alternata, Cylindrocarpon destructans, Leptosphaeria coniothyrium and Epicoccum purpurascens were dominant, while Mammaria echinobotryoides, Phoma leveillei, Kaissleriella subalpina, Botrytis cinerea and Phytophthora cinnamomi occurred less frequently.
The aim of the paper is to characterize some aspects of site conditions in selected places with the occurrence of heather (Calluna vulgaris) within the certain area of the Toruń Basin affected by military activities. Relations of heathlands to the soil cover appear to focus on the position of heather in the ecological succession on presently developing, young sandy soils and regularities of the heather distribution in a mosaic with grasslands in isolated dune fields. Studies were performed at two sites: Stawki and Chorągiewka.Heathlands of this area are connected with nutrient-poor and dry sandy habitats. In the ecological succession, which proceeds in places previously devoid of the vegetation cover and strongly deflated, they occur as a transitional type of vegetation, displacing plants of initial psammophilous community (Spergulo-Corynephoretum) and later giving place to pine forest. In the soil evolution, they are connected with the intermediate stage represented by arenosols (haplic arenosols) - weakly developed but sufficiently acid soils. On deforested, parallel dunes of the Toruń Valley, there are specific regular mosaics of vegetation and soil. Heather occurs on podzolized soils (albic arenosols, haplic podzols) on north-western slopes. Dry grasslands (Calamagrostis epigejos) cover slopes with south-eastern exposition, with soils eroded down to bed-rock and now regenerating to the stage of arenosols (haplic arenosols). Podzolized soils seem not to be developed under heather but rather under the relics of former pine forests preserved from erosion and deflation on less steep and more moist slopes.
Our research was conducted on abandoned fields which had been undergoing spontaneous succession for 40–50 years and then were partly burnt. The main objective of the study was to examine if spontaneous fire in the early successional stage of pine forest causes a decrease in the number of species, diversity and density of seed banks, and an increase in the share of species forming long term persistent seed banks. Standing vegetation and soil seed banks were studied on 20 permanent plots on adjacent burnt and unburnt sites one and twelve years after spontaneous fire. One year after the fire the number of species in the seed banks of both areas was similar (11 and 12 species). In the burnt area the Shannon index and the floristical similarity between the seed bank and standing vegetation were lower, and seed density five times higher than in the unburnt area (15 691.5 m–2 vs.3426.5 m–2). This was mainly the effect of the high number of seedlings of Calluna vulgaris (L.) Hull and Spergula morisonii Boreau germinating from the burnt plots. Twelve years after the fire the number of species in both seed banks had increased little, but seed density in the burnt area (1742.5 m–2) had decreased 16 times, while that of the unburnt area had changed only slightly (2875.5 m–2). At the same time the Shannon index for the burnt area increased considerably, whereas for the unburnt one it did not change. Our study shows that the long-term persistent soil seed bank plays a fundamental role at the beginning of the post-fire regeneration of temperate coniferous forest vegetation. Germination of Calluna seedlings from the burnt soil seed banks in several times higher numbers than from unburnt soil seed banks may suggest that heat from the fire promotes a loss of dormancy in the heather seeds.
Studies on the soil seed banks of fallow lands of different ages were carried out on poor soil abandoned fields and in a fresh coniferous forest in north-eastern Poland. The size and diversity of seed banks was studied with the seedling emergence method. Species abundance (i), density (ii), number of species from different biological groups (iii) and distribution and mean LI value (iv) were analysed as the function of fallow land age. It was found that: (i) species diversity, number of species and ln of density are linear declining function of the fallow land age; (ii) for approx. 25 years the share of diaspores of identified species groups has been relatively similar. Seed banks of 40-50-year-old fallow lands are dominated by Calluna vulgaris, while the seed bank of the old fresh coniferous forest is dominated by dicotyledonous perennials and grasses; (iii) within the first 50 years of succession the persistence of seed banks measured by the Longevity Index increases gradually.
Testate amoebae consist of a group of protists producing protective external coats (tests), which potentially allows them to be used in palaeoecological studies. They are known to be good indicators of several ecological parameters such as water chemistry, moisture and water table level in substrate, and especially peat moisture. Because of their strong dependence on environmental variables it is assumed that each bog microform (e.g. hummock, hollow) is characterized by a different assemblage of testate amoebae. The distribution of testate amoebae assemblages in peat bog of north-eastern Estonia was studied along the gradient from hummock to hollow in the upper 30 cm of the peat layer along a transect of 10 m. The composition and abundance of testate amoebae communities were analyzed in the samples collected (peat sampler, 5 cm diameter) from each sample point (at a distance of 2.5 m from each other) from hummock to hollow. Indicatory species specific to certain bog microforms (representing a set of environmental variables) were found, as well as other species typical for individual environment variables such as depth, peat decomposition degree, and distance to water table or local vegetation. Data analysis showed that distinct bog microforms are better described by abundance of particular testate amoebae species in peat than by species proportions in total abundance of the assemblage. The frequency of occurrence of species with dry environment preference correlates well with arboreal and Calluna vulgaris pollen and high degree of decomposition of peat; it all indicates a dryer environment and possibly is referring to a hummock microform. Amphitrema flavum correlates well with Sphagnum; this correlation increases with the A. flavum shift downwards from Sphagnum up to 4 cm. Testate amoebae assemblages in different bog microforms, even within 10 m, are distinctly different. To pay attention to possible changes of bog microforms in time is therefore crucial for reconstructing the palaeohydrological history of bogs.
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