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71.
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The early sedimentological and ecological developmental stages of a late Vistulian lake in the ?abieniec swamp near ?ód? (central Poland) were analysed by radiometric dating, changes in the frequency of specimens and species composition of Cladocera and multivariate statistical analysis (DCA). The longevity of the lake resulted in a fairly complete sedimentary record from approximately 22 ka to 11 ka cal BP. Species composition and the variability in the frequency of Cladocera specimens has made it possible to distinguish eleven zones of their development, which are well correlated with radiocarbon data. The results were compared to those from other sites of north and central Europe. The initial Cladocera development comprises the richest and oldest late Vistulian Cladocera record in Europe. These cladoceran assemblages show that a deep, oligotrophic, moderately cold-water lake was present at the beginning. It appears that the cladoceran development was mainly due to climate change, but also to changes in locally prevailing conditions in the water body. The high frequency of cladocerans, as well as the presence of cladoceran taxa preferring warmer water, was noted before approximately 16 ka BP. The biota suggests that the Oldest Dryas cooling was not severe and fairly variable in terms of humidity and temperature. The changes in Cladocera composition give evidence of what is described as the Intra-Bølling Cold Oscillation. It is also concluded that the Bølling is represented by two phases in the ?abieniec lake sediments.  相似文献   
73.
The study presents criteria to distinguish some of the nonhuman predation on birds whose remains may also be found at archaeological sites. Specifically, it deals with fragmentation patterns of bird bones in uneaten food remains of the white-tailed eagle Haliaetus albicilla and discusses perforations in victims' bones done by the white-tailed and golden eagles. The food remains show very low degree of fragmentation; bones of the pectoral girdle and wing predominate while head and leg elements are poorly represented. The proportion of perforated sterna differs between the two species of eagles and it is suggested that the differences are attributed to the species of prey rather than the way of handling them by the raptors.  相似文献   
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This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.  相似文献   
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The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.  相似文献   
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The goal of this article is to identify the impact of innovations on growth and stagnation regions in Poland. The research procedure consists of two stages. At stage one, Polish administrative units (voivodeships) were arranged on a scale of economically robust and weak regions following data clustering, indicators organized in line with the following aspects of social and economic growth: (1) population and settlement, (2) the economy structure and the labour market, (3) the technical infrastructure and spatial accessibility and (4) the financial situation and level of affluence. Stage two includes identification of the relation between the regional diversification and the distribution of growth and stagnation regions in Poland which is based on canonical correlation.  相似文献   
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For many years internationalization has not been a strong point of geographical education in post-socialist countries, including Poland. Therefore, all attempts at intensifying it are a real challenge and good practices deserve dissemination. This paper seeks to present the organizational and programme assumptions of a new field of postgraduate study called Cultural industries in the development policies of cities and regions, (Project supported by the European Social Fund under the Human Capital Operational Programme in the years 2013–2015 (Priority IV: Tertiary Education and Science, Measure 4.3: Enhancing the didactic potential of universities in areas of key importance for the Europe 2020 Strategy. UDA-POKL.04.03.00–00-152/12–00).) developed by the staff of the Institute of Socio-Economic Geography and Spatial Management of Adam Mickiewicz University in Poznań (Poland) as a didactic innovation, based on a modular system of education offering wide internationalization possibilities. The analysis focuses on experiences connected with this process. They include classes prepared in cooperation with visiting professors and practitioners from eight universities and European institutions as well as week-long practical placements in Brussels, arranged thanks to a network of experts and institutions specifically established for this purpose. The results obtained help to formulate conclusions and recommendations for higher schools interested in adopting this kind of good practices connected with the development of geographical education.  相似文献   
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ABSTRACT

Sustainable nature-based tourism was brought to the public's attention as a solution to the problem of economic diversification in Central and Eastern European (CEE) communities included in European Ecological Network – N2000. However, Natura 2000 tourism development has not yet proven to be an effective way to boost local economies and the notion of sustainable tourism based on Natura 2000 resources has been challenged by residents of the CEE communities. The study goal was to explore issues concerning Natura 2000 tourism from the perspective of local residents within three municipalities of Ma?opolska in Poland to determine if Natura 2000 is perceived by local residents as a valuable tourism asset. We employed a mix-mode methodology: an in-depth interview and public participation GIS mapping task. The study results highlight several areas of concern regarding resident perspectives of Natura 2000-based tourism: first, the misconception that residents need and want nature-based tourism when other economic activities provide sufficient income; second, the misconception that Natura 2000 is considered a valuable asset when other tourism attractions in a municipality attract more visitors; third, the residents misconception of nature-based tourism itself; and last but not least the importance of engaging with residents when assessing the potential for Natura 2000 tourism. These findings can assist policy-makers and tourism managers with prioritizing avenues for further action.  相似文献   
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