Zarys treści: Autorzy przedstawiają źródła, metody i wyniki analiz przestrzennych, których celem było odtworzenie pierwotnej rzeźby obszaru Zespołu Staromiejskiego w Toruniu i jego bliskich przedmieść. Badania oparte zostały na danych geologicznych, archeologicznych i historycznych. Dane te zebrano i przetransformowano do postaci umożliwiającej wspólną analizę na platformie GIS. Końcowym rezultatem badań jest próba rekonstrukcji rzeźby analizowanego obszaru sprzed lokacji miasta (XIII w.) i jej późniejszych przekształceń, głównie antropogenicznych. Zmiany te zostały scharakteryzowane ilościowo, a pierwotne ukształtowanie rozpatrywanego terenu zwizualizowano w postaci modelu rzeźby.Słowa kluczowe: rekonstrukcja pierwotnej rzeźby terenu, geoinformacja geologiczna, geoinformacja historyczna, Zespół Staromiejski w Toruniu Abstract: The authors present the sources, methods and results of the spatial analyses, the aim of which was to recreate the original relief of the area of the Old Town of Toruń and its close suburbs. The researches were based on the geological, archaeological and historical data. These data were collected and transformed into the form which permits their joint analysis in the GIS. The outcome of the study is an attempt to reconstruct the relief of the analysed area before the foundation of the town (13 th c.) and its subsequent transformations, mainly anthropogenic. These changes were characterised quantitatively, and the original relief of the area in question was visualised as a relief model.

The paper presents the results of research into toxic metal concentrations in the surface layer of bottom sediments in Lake Gopło. The research objectives were to identify the levels and spatial variability of Cu, Pb, Cd, Zn, Ni, Cr, As and Hg concentrations, their potential sources and the determinants of pollution levels. Metal contamination of the sediments was assessed using the geoaccumulation index (Igeo), pollution load index (PLI) and ecological risk index (RI). Chemometric methods (Pearson correlation, principal component analysis (PCA) and cluster analysis (CA) were used to determine the relationship between sampling sites and concentrations of toxic metals, thereby identifying the sources of contamination. The research found that grain-size composition, carbonate content and organic matter content in the bottom surface sediments of Lake Gopło are all characterised by low diversity. Therefore, the lithological features of the sediments are not a major factor in the concentrations and spatial variability of the metals. It was found that the metal concentrations in the great majority of samples were above regional geochemical background levels. The geochemical indices (Igeo, PLI, RI) indicate that the degree of toxic metal pollution in the sediments is slight in the central and southern parts of the lake and high in the northern part. The chemical analysis results showed that the samples in the central and southern parts of the lake differ little in their shares and concentrations of individual metals. This provides evidence that, as well as geogenic sources, their presence in sediments can be associated with non-point sources related to agricultural activities and with atmospheric sources (mainly the products of fossil fuel combustion). The higher concentrations of metals (especially Ni, Cd, Cr and Hg) in the northern part of the lake are influenced by the supply of industrial and communal pollutants from the lakeside town of Kruszwica. A factor limiting the migration of pollutants from the northern part of the lake towards the south is the lake’s morphology of the lake, which hinders water exchange between the northern part and the rest of the lake.

Abstract. This paper presents the results of the study on the concentration of heavy metals and persistent organic pollutants (POPs), including PAHs and PCBs, in the bottom sediments of Lake Gopło. This lake is significantly elongated (about 25 km); its longitudinal profile is diversified, and there are deeps and thresholds impeding the flow of water. The shoreline is varied, which is characteristic of tunnel valley lakes. The catchment has a typical agricultural character with a point arrangement of industrial centres. The analysis of the diversity of the concentration of heavy metals and POPs was based on 37 samples from two representative cores: one collected in the northern part of the lake, the catchment of which shows an industrial character, and the second one in the southern part where the catchment is agricultural in character. In the sediments, the content of the following heavy metals was analysed: Cu, Pb, Cd, Zn, Ni, Cr, Hg and As, as well as PAHs and PCBs. The sediment age was determined by the 210 Pb dating method. In order to assess the contamination level of the bottom sediments with heavy metals, the contamination factor (CF) and degree of contamination (DC) were calculated. Moreover, the impact of the changes in the catchment's land use over the past 100 years was determined. The results showed that the sediments from the industrial part of the lake significantly exceed the geochemical background for both the heavy metals from the group identified as industrial pollution and from the group of agricultural pollutants. The southern core shows only a slight increase in the amount of pollution from the agricultural group, lack of industrial pollution and a low degree of contamination. A slight increase in persistent organic pollutants is also recorded, without any apparent effect on the state of the deposited sediment. The 210 PB dating enabled the main stages of human impact to be determined: the pre-industrial revolution, from the beginning of industrialisation to the 1950s, intensive human impact from the 1960s to the 1980s, and a gradual decrease in the human impact starting from the 1990s. In addition, attention was paid to the changing sedimentation rate.

The main aim of the paper was a visual comparison of lichen distribution with urban environmental factors. This paper presents a cartographic method for representing the spatial distribution of anthropogenic and natural factors in atmospheric air pollution and prevalent elements of the natural environment and their correlation to occurrences of two selected lichen speciesthe acidophilous Hypogymnia physodes and the nitrophilous Xanthoria parietina in the area of Toruń (Central Poland). Lichens are a good indicator of changes in habitat conditions. Analyses of the occurrence of lichens in Toruń were conducted for data covering a period of more than 60 years. A choropleth map method (a square tile grid map) was used, based on a grid of 144 one-kilometre squares (ATPOL). An inventory of taxa was made in 137 squares (localities). This recorded the type of substrate and abundance (extent) of occurrence.

Abstract. In this study modern sediments of the lower Vistula River were investigated to determine the relationship between the structure and texture (grain size, rounding and frosting) of the deposits and the possibility of their zeroing. The samples of modern fluvial deposits were collected from the lower Vistula River at two sites in Toruń and Ciechocinek. Sand bars newly emerged from the river were selected for testing. The coarse quartz grains were separated for OSL measurements. The single-aliquot regenerative (SAR) technique was applied for measuring equivalent doses from multigrain aliquots. The obtained dose estimates were found to be very low, proving the reliability of the OSL zeroing assumption. The dose rates were estimated by gamma-ray spectrometry, demonstrating homogeneity of the radiation field. Analysis did not show significant relationships between the examined sediments' capacity to zeroing and their structural and textural characteristics, or the sampling site. The obtained OSL ages of the studied sediments date back hundreds of years and are probably overestimated. The results related to fossil sediments of bars of the age of thousands of years confirm their suitability for the OSL dating method.