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The paper reports results of a biometric study of four features of Leymus arenarius (L.) Hochst. caryopses on the basis of 23 samples collected at marine and inland sites. The productivity of caryopses in the spike and the strength of their germination were determined.
Grasshoppers and katydids (Orthoptera) were studied on sand dunes of the Hel Peninsula in northern Poland in 2013. Altogether, 11 species of grasshoppers and katydids were identified, three of them can be regarded as elements of the fauna characteristic for sand dunes. Species diversity and population density was higher in the seaside with sparse vegetation than in the neighboring pine forest. The reported low species richness is comparable to other peninsula covered by sand. Myrmeleotettix maculates was most abundant, particularly by the seaside with low shrubs and Tetrix bipuncata occurred frequently in each habitat, but especially on the forest gaps.
The present paper aims at describing the biota of lichens of the Zadroże Dune and its adjacent area in Toruń. The research on lichens was conducted during the years 2005-2006. The data on lichens come from my own research and literature. Altogether, the occurrence of 82 lichen taxa was recorded in the investigated area, including 74 species recorded during my own research. Due to the availability of habitats and substrata, terricolous species dominate here, mainly from the genus Cladonia and Cetraria. Particularly noteworthy are rare, endangered and protected species from this area e.g. Peltigera canina, Polyblastia agraria, Rinodina conradii and Stereocaulon condensatum
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 paper analyses the results of field investigations into the evolution of the shoreline and dune toe positions in a multi-bar, dissipative coastal zone. The correlations between the changes in the shoreline and the dune toe range from −0.4 to 0.8. It is most often the case that the dune toe is stable while the shoreline moves. Consistent cross-shore migration is slightly more likely to happen than the divergent or convergent movements of both lines. Shoreline retreat and advance attain respective rates of 0.7 m day−1 and 0.4 m day−1. Deep-water wave energy of about 50 kJ m−1 constitutes the boundary between shore accumulation and erosion.
The profile structure of soils developed on the inpeatland dunes in the Biebrza River Valley and Narew River Valley suggested that they are rusty soils. However, the chemical analyses indicated the distinct accumulation of analyzed elements, mainly iron and aluminium, in the enrichment horizon (B). The determination of studied soils systematic position on the base of podzolic soil diagnostic criteria used by Systematics of Polish Soils and WRB classification as well as on the base of indicators proposed by various authors was the aim of the study. The results revealed that soils developed on dunes in the Biebrza River Valley can be determined as rusty soils, while on dunes located in the Narew River Valley, the podzol soils have developed. The absence of eluvial horizon in these soils presumably resulted from its mixing with humus horizon during ploughing in the past.
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.
Communities of bees (Apiformes) were studied in the Wolin National Park in 2002-2003. The Park is located on the island of Wolin in northwestern Poland, at the southern coast of the Baltic Sea. In total, 133 bee species were recorded there in various habitats. This study shows that the major role in protection of bee communities is played by xerothermic and sandy grasslands. They are distinguished by the highest species diversity of Apiformes, including Anthophora bimaculata and its nest parasite Ammobates punctatus (rare in mainland Poland). In contrast, coastal grey dunes support mostly bumblebees, including cuckoo bumblebees.
In 1991-1993,199 noctuid species were recorded from coastal sand dune habitats in the nature reserve „Mierzeja" in the Słowiński National Park. The species are listed in a table according to their systematic position, their localities, abundance and period of emergence of imagines being given. Typical sand dune habitats of Mierzeja Gardzieńsko-Łebska - Elymo-Ammophiletum, Helichryso-Jasionetum and Empetro nigri-Pinetum - are characterized with respect to their noctuid fauna. Noctua janthe (Borkh.) has been recorded from Poland for the first time.
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.
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.
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