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This paper compares pollen spectra derived from modified Tauber traps and moss samples adjacent to pollen traps from four sites different in type of vegetation and openness of the landscape in Tuchola Forest. The length of the pollen deposition period covered by an individual moss sample was a matter of discussion, as well as accumulated values of pollen grains in green gametophytes (A) and basal part of moss (B). Compared to pollen traps, mosses tend to accumulate more Pinus grains. The investigated moss samples (A+B) usually contain pollen from a period between one and two years. Pine, spruce, oak and beech pollen deposited more pollen almost always in the subsample A.
The paper presents the results of the research on the pollen seasons of hazel (Corylus), alder (Alnus) and birch (Betula) in 2014 and 2016. The samples were collected gravimetrically at weekly intervals. The deposition values were converted into the pollen grains concentration in 1 m3 of air. The analysis of the pollen seasons was conducted based on the properties of the seasons: beginning, end, season duration, annual totals of pollen and maximum concentrations. The courses of the both compared pollen seasons differed. In 2014, the tree pollen season began two weeks later than in 2016, a year that was marked by high annual totals of pollen counts and maximum pollen concentrations of alder and birch. Only hazel showed higher values in 2014.
The study presents data on the distribution of selected species of lichens – Cladonia furcata (Huds.) Schrad., C. rangiferina (L.) Weber ex F.H. Wigg. and C. uncialis (L.) Weber ex F.H. Wigg. in Toruń and along its southern boundary - on a heathland on the military training ground. A comparison was carried out of the research findings on the occurrence of the analysed species against variable habitat conditions over a period of nearly 40 years. The occurrence of Cladonia uncialis was most frequently observed within the city, in the habitats of Calluna vulgaris. A tendency was shown of selected lichen species to spread in the investigated area.
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.
In 2O15, the structure of a forest stand growing on former agricultural land in subunit 277n of the Przymuszewo Forest Division (Regional Directorate of State Forests RDSF in Toruń) was described. The study area was afforested in 199O - mostly with Scots pine (Pinus sylvestris L.), silver birch (Betula pendula Roth) and several seedlings of the European beech – after many years of agricultural cultivation of grain and potato crops. Characteristics of the forest stand comprised the following parameters: species composition and species diversity, density of individual components, the average tree diameter at breast height (DBH), and the height and aboveground biomass of trees divided into individual species. The species structure, dendrometric characteristics and spatial dis- tribution of trees studied in 2015 were compared with the situation assessed in 2000.Based on DBH and height values, as well as the use of dendrometric tables and basic wood density for tree species, the above- ground biomass and total biomass of trees with a minimum diameter of 7 cm were calculated. The aboveground and total biomass for trees with DBH less than 7 cm was calculated on the basis of density and weight of trees according to the classification into species and height classes. The aboveground and total biomass of the whole tree stand, including spontaneous non-native and invasive Padus serotina Ehrh., was compared with the standing biomass of agricultural areas in the Tuchola Forest region as well as with other Scots pine-silver birch plantations on former agricultural lands described in ecological literature. The paper presents also the differences in assessments of aboveground pine biomass at the study site obtained when using conver- sion factors established during direct measurements carried out in forests of the Przymuszewo Forest Division and conversion factors applied during inventories conducted in Poland according to the IPCC recommendations for international reporting submitted to the United Nations Economic Commission for Europe, FAO and UNFCCC
The results of palynological analyses of the Holocene deposits and modern pollen deposition in Poland and Finland are used to illustrate the progress in pollen analysis - the main palaeoecological method. The increased potential of modern palaeoecology for reconstruction of vegetation and for drawing conclusions on other environmental variables (climate, water conditions, landscape, anthropogenic disturbances) is demonstrated. Pollen analysis - develops at present interpretive tools for precise reconstruction of the structure and composition of vegetation and climate conditions. The progress consists in the quantitative presentation of pollenvegetation-climate relationships based on the examination of modern pollen deposition. The application of numerical analyses to pollen data allows correlating pollen spectrum features with the landscape/vegetation type. Special attention is paid to the Holocene vegetation changes of the transitional zone between boreal forest and tundra in the areas subjected to weak anthropopression (e.g. Lapland), which reflect climatic changes. Databases of modern pollen analogues are based on analysis of samples of surface mosses and contents of Tauber traps. These traps are used in Poland in investigations conducted as a part of the Pollen Monitoring Programme (http://pmp.oulu.fi). The correlation of Tauber-trap data with aerobiological ones contributes to understanding of the relationship between pollen production and climate elements. Additionally, the precise C14 dating allows a near-annual resolution in fossil deposits to be obtained more frequently. Due to time scales comprising hundreds of years, pollen analysis can provide means to resolve questions inaccessible for direct observation.
In the mid-19th century, the sheep industry played a considerable part in sheep breeding in Pomerania. Livestock grazing took place on extensive heathlands developed as a result of land deforestation performed in the 17th and 18th century, as well as during and after the Napoleonic wars. The sheep industry and the related textile craft developed until the 1890s when the Prussian government began the restoration of forests after the period of their excessive exploitation. The Prussian government policy contributed to the afforestation and the growing forest range through purchasing of landed estates, in particular the Polish ones, and creating forest divisions, followed by reconstruction of forests. This paper presents the history of the Widno estate belonging to Mr. Konstanty Przytarski. The estate was located in the northern part of the present-day Zaborski Landscape Park, near the town of Brusy and Chojnice. In 1894, the estate was sold to the Prussian forest administration. The paper presents changes in the land use and the forest above-ground biomass. Furthermore, changes in the structure of the energy flow network through the natural and production-cultural subsystems are presented. The network structure was analysed according to the methodology presented by H.T. Odum. Data contained in the sales contract of the Widno estate were used in the analysis, together with a forest inventory book of the Prussian Forest Inspectorate Zwangshoff and inventory books of the Polish Inspectorate Przymuszewo. The study highlighted the increasing role of sheep breeding on small family farms established by employees of the forest division on the leased lands. This form of activity refers to the economic traditions in the region of Zabory.
The paper presents the location and general description of habitats and plant communities with common milkweed occurring within the city limits of Toruń. The data set comprised new localities of this species as well as those where Asclepias syriaca has been observed for several years but the sites have not been described in the ecological literature. Relevés made at these sites were compared with those described by Puchałka et al. (2013) from three sites of Asclepias syriaca in Toruń. A larger set of new sites included in the analysis allows for a more accurate description of the impact exerted by some ecological factors, e.g. afforestation, on the growth of the studied species. As evidenced by the new sites of Asclepias syriaca found recently in Toruń and the surrounding area, it is necessary to monitor the dynamics of the population and to undertake the research on the impact of common milkweed on plant communities.
This study presents changes in the quality of habitats between 1926 and 2013 in permanent units of forest division restored in the 19th century as a result of afforestation carried out in the landscape dominated by heaths and xerothermic grasslands. The research was conducted in the Zaborski Landscape Park, located in the north-western part of the Tuchola Forest − one of the largest forest complexes in Poland. Changes in the habitat quality were determined based on data included in seven consecutive inventory books. Assessment according to the 5-point quality scale was performed on the basis of average height reached by a pine forest stand of a certain age occurring in particular forest subsections. It has been found that the quality of habitat increased over 87 years by two classes, on average from IV to II. The number of species, especially deciduous trees and shrubs listed in inventory books, was an additional parameter expressing the habitat quality. The extent of habitat changes was also determined based on the types of syntaxa, which are represented by relevés forming the time series and made more or less at the same sites by different authors in 1961, 2002 and 2013, i.e. over the period of 52 years. Temporal changes in the structure of phytocoenoses and their syntaxonomic affiliation were determined using the classification and ordination methods. It has been found that in the study area and within the studied time horizon, there was a recession of dry coniferous forest which developed towards mesic (fresh) pine forests. Whereas within the fresh coniferous forest, there were transitions from the poor cladonietosum variant to the mesotrophic typicum variant, or from the typicum variant towards the fertile variant with a large contribution of Fagus sylvatica in the main tree layer and undergrowth. A change in the forest type from a pine monoculture to mixed pine-beech forest was also reflected in the spectrum of modern pollen deposition collected after annual exposures of Tauber traps. In this case, the observations were performed by the same research team over 15 years.
Differences between modern pollen rains in three types of phytocoenoses were studied in two regions, i.e. Tuchola Forest and Toruń Basin. The phytocoenoses in question were heaths, young pine-birch growths and mature pine tree stands, which form a temporal sequence and spatial mosaic in the landscape. In order to compare the structure of pollen samples, phytocoenoses and the landscape, the methods of numerical taxonomy were applied. An increase in the average number of sporomorphs was recorded, as well as in the taxonomic diversity of the pollen spectrum in this temporal sequence arranged from non-forest communities through young growths to mature forests. In the subsequent developmental stages, also the percentage contribution of Pinus pollen increased, as well as the total contribution of arboreal pollen (AP). The increase in the percentage contribution of arboreal pollen is accompanied by the decrease in the contribution of non-arboreal pollen (NAP), including Calluna and Ericaceae. Also a small increase in the number of species was observed. With the increased pine domination, however, the diversity of pollen types (expressed by rarefaction and Shannon-Wiener indices) decreases. As a result of the performed analyses, it was also found that the species composition of phytocoenoses and a pollen spectrum differs considerably, because the import of pollen from further areas exerts a significant influence on the structure of a palynological sample. The genus Calluna is the only type of plants characterized by a strong relationship between the occurrence in a phytocoenosis and in a surface pollen sample. Similarity between the taxa composition of a pollen spectrum and the landscape structure, consisting of a mosaic of phytocoenoses, seems to be higher than between a pollen sample and a phytocoenosis from which that sample was collected. The latter thesis, however, needs to be confirmed by further researches.
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