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31.
Der letzte Bericht des Intergovernmental Panel on Climate Change (IPCC 2007) erl?utert die weltweiten Auswirkungen des Klimawandels deutlich – allerdings aus globaler Sicht. Um zu kl?ren wie sich das regionale Klima in ?sterreich ver?ndern wird, wurde mit dem Projekt „reclip:more“ (Research for Climate Protection: Model Run Evaluation) eine erste kleinr?umige Datenbasis für Klimaschutz und Klimafolgenforschung für ?sterreich generiert. Klimaszenarien wurden mittels regionaler Klimamodelle (RCMs) für die Alpen als 10 × 10-Kilometer-Raster und mit anschlie?endem Downscaling für ?sterreich mit einer Zielaufl?sung 1 km entwickelt. Die RCMs wurden mit ERA-40 Reanalyse-Daten der Vergangenheit und Daten eines Zukunftsszenarios des globalen Klimamodells (GCM) ECHAM5 angetrieben, um retrospektive (1981 bis 1990) und künftige (2041 bis 2050) Klimadatens?tze für die Alpen zu berechnen und M?glichkeiten und Unsicherheiten der Modelle und Downscaling-Methoden für die Alpen zu evaluieren. Die nun vorliegenden Datens?tze und weitere, die im Folgeprojekt „reclip:century“ für alternative Treibhausgasszenarien bis 2100 berechnet werden, dienen dazu als Basis für Aussagen über ?kologische und sozio?konomische Entwicklungen im Hinblick auf den Klimawandel.  相似文献   
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Mexico’s Central Highlands form one of Mesoamerica’s fundamental cultural seams, a point of overlap between two traditions, one to the east and the other to the west. Although this area is usually included in the west, it can be more productively viewed as an interface, the physical space where people, goods, and ideas passed from one side to the other, and thus it holds many keys for our understanding of emerging social complexity in Mesoamerica. In reviewing the last two decades of Formative period (1500 BC–AD 100) research in this crucial territory, we focus on themes that reveal the variation and dynamism of interregional interaction, including the formation of regional traditions, exchange systems, and foreign “influence,” and others that help contextualize the events and processes of that time, like household studies and environmental degradation. We stress that this part of Mexico is undergoing relentless development so time is of the essence if we are to broaden our perspectives on social evolution in the Central Highlands. This issue cannot be resolved by rescue and salvage work because it requires long-term, interdisciplinary projects to unravel multifaceted problems.  相似文献   
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This paper demonstrates the results of analyses of Cladocera, pollen, plant macrofossil, lithological and radiocarbon data recovered from a mire located in the Rawka River valley in central Poland. These studies permit to recognise the development of hydrology phases in Kopanicha mire and give insight into Holocene fluvial dynamics of the system; radiocarbon dating partly allowed da-ting of the patterns of Holocene valley floor development of the Rawka River. The Kopanicha mire was formed during the Atlantic period. At that time, an oxbow lake formed, becoming a mire during the Subboreal and possibly Subatlantic periods. The high sensitivity of the oxbow lakes, fens, fauna, and flora remains to climate variations - especially to changes in water level connected with the ag-gradation-erosion cycle of rivers - allows the reconstruction of the palaeoecological changes that oc-curred in the mire. The frequency and timing of hydroclimatic oscillations at Kopanicha show strong similarities to records from other sites in Poland. Changes in Cladocera frequency and plant assem-blages were mostly influenced by the Rawka River which controlled the hydrological regime of the mire. The main factors controlling the presence of Cladocera taxa were the water level and the pres-ence of favourable conditions in the mire (e.g. pH, vegetation). Most of the changes occurred in re-sponse to climate changes, but some of them were connected with local factors.  相似文献   
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The aim of this paper is to present and discuss empirical evidence on the dynamics of occupation and site formation processes from contemporary mobile campsites in Northwest Siberia. The questions posed are derived generally from archaeological studies of Upper Paleolithic record in Europe. We document the active Nenets summer camps at lakes and the abandoned winter and spring camps in the open tundra and the forest tundra. Analysis of the floral and zoological resources shows that plant resources and fish are available predominantly in the summer while reindeer are abundant in these regions in fall and winter when they return from summer pastures further north. When natural resources are not available, groups supplement with food purchased at shops. Within these living camps, “structures évidentes” and “structures latentes” of classical French paleoethnology cannot be distinguished as clearly as at Upper Paleolithic sites: and architectural remains, ash from hearths, and other objects may be removed from the central areas towards the site peripheries. However the investigated camps preserve a discrete structure with interior living areas (including children’s playgrounds), exterior areas with evidence of reindeer carcass processing, woodworking, and other activities, peripheral toss zones, and dispersed activity remains in the surrounding landscape.  相似文献   
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Different ideas are proposed all the time in archaeology. These often rise or fall based on how well they predict objective, measureable characteristics of the archaeological record. But other ideas are more paradigmatic, concerned with how we think about the archaeological record rather than the record itself. What determines which ideas rise or fall? This essay considers the specific question of why Lewis Binford’s middle-range approach became more prevalent over the very similar formation-process approach of Michael Schiffer in the 1970s and 1980s. It is hypothesized that while an approach’s ability to predict objective characteristics of the archaeological record is one selective factor, in this particular case, other factors, including personality and, especially, the association between Binford’s approach and significant, long-standing problems of prehistory, were also significant selective factors.  相似文献   
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