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Standort - Seit Jahrzehnten wird Bier größtenteils in standardisierten Wertschöpfungsketten produziert, wobei die Kontexte der Rohstofferzeugung kaum mehr nachvollziehbar erscheinen....  相似文献   
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The elucidation of spatial variation in the landscape can indicate potential wildlife habitats or breeding sites for vectors, such as ticks or mosquitoes, which cause a range of diseases. Information from remotely sensed data could aid the delineation of vegetation distribution on the ground in areas where local knowledge is limited. The data from digital images are often difficult to interpret because of pixel-to-pixel variation, that is, noise, and complex variation at more than one spatial scale. Landsat Thematic Mapper Plus (ETM+) and Satellite Pour l'Observation de La Terre (SPOT) image data were analyzed for an area close to Douna in Mali, West Africa. The variograms of the normalized difference vegetation index (NDVI) from both types of image data were nested. The parameters of the nested variogram function from the Landsat ETM+ data were used to design the sampling for a ground survey of soil and vegetation data. Variograms of the soil and vegetation data showed that their variation was anisotropic and their scales of variation were similar to those of NDVI from the SPOT data. The short- and long-range components of variation in the SPOT data were filtered out separately by factorial kriging. The map of the short-range component appears to represent the patterns of vegetation and associated shallow slopes and drainage channels of the tiger bush system. The map of the long-range component also appeared to relate to broader patterns in the tiger bush and to gentle undulations in the topography. The results suggest that the types of image data analyzed in this study could be used to identify areas with more moisture in semiarid regions that could support wildlife and also be potential vector breeding sites.  相似文献   
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It has recently been suggested that the Laacher See volcanic eruption, which occurred around 13,000 years ago, initiated significant demographic fluctuations along the northern periphery of Late Glacial human settlement and that these led to a number of material culture transformations. The origins of the Southern Scandinavian Bromme culture and the northeastern European Perstunian culture as well as the temporary abandonment of Central European regions have been linked to this eruption. However, it remains unclear precisely which aspects of the eruption stimulated Late Glacial foragers to abandon their traditional ways of life. Paradoxically, the culture–historical impact of the eruption appears greater further away from the eruptive centre. Here, we investigate one potential middle-range link between the Laacher See eruption and Late Glacial fauna and foragers: tephra as a health hazard. We use laser-diffraction particle-size analysis to quantitatively investigate tephra from one site with a secure Late Glacial archaeological deposit. In addition, we use values previously reported in the literature and a predictive model to calculate the hazard potential along a transect of two of the three major Laacher See tephra fans. Our results show that the Laacher See tephra may have posed a potential health hazard and that its hazard potential may have increased with distance from the vent. To our knowledge this is the only study that attempts to quantify the changing grain-size composition of tephra fall-out longitudinally in this way, at least with regard to a prehistoric eruption. We close by discussing, more speculatively, other possible health-pertinent effects of the Laacher See eruption and suggest ways in which future work can further evaluate the impact of this eruption on Late Glacial populations.  相似文献   
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This paper concerns the identification and explanation of change in prehistoric extractive metallurgical behaviour in the Iron Age Khao Wong Prachan Valley of central Thailand. This metallurgical complex is amongst the largest in Eurasia and constitutes Southeast Asia's only documented pre-modern copper-smelting evidence. The two Iron Age smelting sites investigated, Non Pa Wai (NPW) and Nil Kham Haeng (NKH), provide a sequence of metallurgical consumption and production evidence from c. 500 BCE to c. 500 CE. The enormous quantity of industrial waste at these sites suggests they were probably major copper supply nodes within ancient Southeast Asian metal exchange networks. Seventy-six excavated samples of mineral, technical ceramic and slag from NPW and NKH were analysed in hand specimen, microstructurally by reflected-light microscopy and scanning electron microscopy and chemically by polarising energy-dispersive X-ray fluorescence spectrometry and scanning electron microscopy with energy-dispersive X-ray fluorescence spectrometry. The analytical data were used to generate detailed technological reconstructions of copper-smelting behaviour at the two sites, which were refined by a programme of field experimentation. Results indicate an approximately 1,000-year trend of Valley copper smelters' improving technical proficiency from what may be an experimental phase of production in the mid-first millennium BCE. This amelioration in production was accompanied by a substantial increase in the human effort of copper extraction. This shift in local ‘metallurgical ethos’ is interpreted as a response to rising regional demand for copper in late prehistory.  相似文献   
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