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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.
The floral and phytosociological research conducted between 1998-2001 in the area of the artillery range shows that there are 460 different species, including 363 vascular plants and 96 algae, bryophytes and lichens. The aforementioned count includes 45 taxa that are fully or partially protected. In the investigated area there are 30 species of vascular plants and 13 lichen species endangered to a different extent, referring to the scale of the whole region, for example: Aster amellus, Prunella grandiflora, Bryoria fuscescens, B. subcana, Peltigera praetextata and Ramalina fraxinea.Out of 335 species recorded in the same area by German researchers in the late 19th century and the early 20th century, the occurrence of 270 species was confirmed by our research, which constitutes 80.6%. The following species are considered as extinct, since they were not found again in the area: Adenophora liliifolia, Cephalanthera damasonium, C. rubra, Dracocephalum ruyschiana and Gladiolus paluster. During the one hundred years, which separate the two research projects, 95 new species appeared in the studied area, mostly archaeophytes and kenophytes. According to the phytosociological research, there are 8 plant associations and one plant community in the unforested part of the range. Among the most rare associations, the following should be mentioned: Caricetum arenariae, Caricetum ligericae and Festuco-Koelerietum glaucae. Calamagrostietum epigeji, Corniculario-Corynephoretum, Arctostaphylo-Callunetum are typical associations of this area. The association Scorzonero purpureae-Stipetum joannis and the community of Salix acutifolia-Epipactis atrorubens are the most valuable ones. They will become the most endangered associations if the excessive pressure by the army or the highway construction should cease in the future. To preserve the particularly valuable species and plant associations, new active preservation forms should be introduced in the whole area of the artillery range, especially after cessation of the excessive military exploitation. A part of the artillery range called "Piaski" should be protected as a sanctuary because of the association Scorzonero purpureae-Stipetum joannis, which occurs only here.
Dunes are generally found in Poland either along the seacoast or inland, mainly in river valleys and on glaciofluvial outwash fans. The position of the dune fields of the Toruń Basin is unique also due to the fact that it is dominated by large dune forms, while the western part of the European sand belt is dominated by aeolian coversands. Dunes in the Toruń Basin are found on all terraces and make up vast clusters (complexes). W. Mrózek (1958) delimited there six dune fields. The dunes located in the Toruń Basin take the shape of crescent (parabolic) forms, simple ramparts (longitudinal and transversal) and irregular hilly forms. Additionally, there are numerous vast and plain areas covered with aeolian sand up to 4-5 m deep, which contain scattered irregular low dunes. The dunes of the Toruń Basin are mainly built of fine-grained and medium-grained sands which come from the local substratum of fluvioglacial and river deposits. The results of the studies on aeolian deposits carried out in the in Europe indicate that the earliest aeolian series (Older Coversand I, van der Hammen 1971) were deposited as early as Late Pleniglacial. In Poland this series has not been recognized, although the river deposits of that age have a larger content of quartz grain abraded in aeolian environment (Kozarski 1990; Manikowska 1991; Goździk 1991). New research claims in the Toruń Basin that the dunes formed chifly in the Younger Dryas, but probably also in the Older Dryas and even in the Preboreal.
The relief of the Zadroże Dune was described, as well as the comparison was done on its vegetation cover and the flora in its two phases of the development, i.e. before the afforestation of the dune and approximately 60 years after reconstruction of the forest. The first state was described in the paper dated 1949. During that period the dune constituted the first common study area for the research team consisting of ecologists and geographers from the Nicolaus Copernicus University. Our contemporary scientific studies were carried out in 2009. In the comparative analysis, a particular attention was paid to the distribution, the number and the size of heath patches with Arctostaphylos uva-ursi. In the description of the contemporary state of vegetation, the structure and the biomass of tree stands were included. The GIS and GPS technologies were applied in the comparative analysis of the vegetation, in the comparison of the former and contemporary cartographic materials, aerial and satellite images, as well as in the development of a digital elevation model. As a result of comparisons of the vegetation cover, it was found that the surface area of heaths decreased from 59.21 ares in 1948 to 2.96 ares in 2009. As a result of comparisons of the flora, it was found that 7 and 26 species of lichens occurred in 1948 and 2009 respectively, 5 and 42 species of mosses, 0 and 7 species of liverworts, as well as 102 and 204 species of vascular plants. The number of families, within which the species of vascular plants are classified, increased from 31 to 52. The compared floras have only 66 species in common. The percentage contribution of geographical and historical groups has undergone only inconsiderable changes during the 60-year period. Contribution proportions of non-synanthropic spontaneophytes and apophytes has changed slightly. Whereas, the contribution of alien species, mainly kenophytes and ergasiophytes significantly increased. This paper discuss the significance of natural and anthropogenic factors, which brought about this considerable range of transformations in the species composition and in the contribution of alien species.
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