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81.
The number and geographical distribution of the aged, and how the distribution changes over time, have captured the attention of geographical gerontologists; the complexity and spatially differentiated nature of ageing is of considerable practical and theoretical import. This article seeks to link the traditional concerns of population geography to the social and spatial relations between old people, their health and places of residence and care. It does presuppose, however, that patterns and processes at the sub‐national level are also taken into account. Therefore, the aim of the article is to identify the aged and the localities or regions where they reside, within the particular context of a Polish post‐socialist society that has recently become integrated into the European mainstream. As such it is potentially subject to a double transition, where the political and economic changes cross path with the second demographic transition. To identify interrelationships between ageing and post‐socialist transition, areas vulnerable to ageing are defined using ageing indices. Projections of the share of elderly up to 2030, based on a component cohort method, are made with a view to identifying future change in the spatial patterns of ageing. Regional patterns of ageing are presented in social, political or economic context, to show their relation to the structural changes that societies such as Poland have been passing through during the period of transition to democracy and a market economy or are likely to go through in the near future.  相似文献   
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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   
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The absolute chronology of Late Bronze and Early Iron Ages in Polish territories is a result of long-term and complex research. Here, we have investigated the absolute dating of two sites, namely K?y?ów, a cemetery of the Tarnobrzeg Lusatian culture, and Jaros?aw, a settlement spanning from the late phase of the former to Pomeranian culture, possibly with Jastorf elements. Having been spurred by promising results of thermoluminescence (TL) dating of medieval and Przeworsk materials, we have employed it in those situations, where no other chronometric methods seem to be efficient. TL dating has been combined with typological analysis of the dated pottery and, partially, with radiocarbon method. Albeit the produced TL dates do not represent the level of sought-for fine chronological resolution, they indicate the temporal trends and corroborate the typological research. Our study has shown the potential of TL dating for periods with plateaus on 14C calibration curve. We also have dealt with unexpected TL ages and suggested some solutions of the problem. Finally, we have demonstrated that the condition sine qua non for archaeological interpretation of TL dates is a thorough stylistic-chronological analysis of dated pottery and clear understanding of relations between chronometric dates and the archaeological event to be dated.  相似文献   
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Multi-proxy analysis (sedimentological, palaeobotanical, geochemical data and results of radiocarbon dating) of the biogenic sediments from a small mire ecosystem in the Sandomierz Basin (SE Poland) is presented. The ecosystem contains a full hydroseral sequence from minerotrophic to ombrotrophic wetland. It is one of the few sites in this region which is so thoroughly investigated in terms of the palaeoenvironmental record. Changes in the water supply of the mire area, and consequently the changes in the plant and sediment succession, were well correlated with the regional tendencies in precipitation and temperature during the Late Glacial/Holocene transition and in the Holocene. Human impact is very well recorded in pollen diagram from the Subboreal period.  相似文献   
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Herding and farming coexisted in Central Asia for several thousand years as main options of preindustrial economic production. The relationship between people practicing different variants of these modes of subsistence is known to have been dynamic. Among the many possible explanations, we explore this dynamic by modeling mechanisms that connect aggregate decisions to land use patterns. Within the framework of the SimulPast project, we show here the results from step 1 of our modeling program: the Musical Chairs Model. This abstract agent-based model describes a mechanism of competition for land use between farming and herding. The aim is the exploration of how mobility, intensity, and interdependence of activities can influence land use pattern. After performing a set of experiments within the framework of this model, we compare the implications of each condition for the corroboration of specific land use patterns. Some historical and archaeological implications are also discussed. We suggest that the overall extension of farming in oases can be explained by the competition for land use between farming and herding, assuming that it develops with little or no interference of climatic, geographical, and historical contingencies.  相似文献   
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