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11.
Metasequoia glyptostroboides is considered to be a species highly resistant to harmful environmental factors. For this reason it has been introduced to the cities. The climate of Krakow differs from that in its natural range in China. The research was focused on 40-year-old trees, planted in Kraków on fertile alluvial soils with a low level of ground water, in the vicinity of the steelworks. During the period of the highest level of air pollution in the 1970s and 1980s, the radial increment of investigated trees showed an increasing trend. At the end of the 1980s, when the emissions were reduced, a decreasing trend in radial growth was recorded. Throughout the entire period of their life the investi-gated trees have shown high homogeneity of short-term growth reactions. The sensitivity chronology of the trees was characterized by a high representativeness and a strong high-frequency signal. This may indicate that the investigated trees have shown a large sensitivity to climatic factors. The positive effect on the radial growth of Metasequoia had a cold September in the previous year, and also a cold January, April and May in the year of ring formation. Positive impact on the growth of trees had also the high precipitation occurring in April and August, as well as high air humidity in the spring of the year of ring formation. In the period 1974–2011 fifteen signature years were found. The analysis of the climatic conditions in these years confirms the results of the statistical analyses.  相似文献   
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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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Although written sources indicate that falconry or hawking was very popular already in early medieval Poland, there is no hard zooarchaeological evidence that would support it. So far, only two studies based on animal remains suggested hawking in medieval Poland. The purpose of this study was to examine all published zooarchaeological reports from all archaeological sites in Poland and check for possible clues of hawking. Altogether, 281 remains of 12 species of diurnal birds of prey were recorded from 38 sites (49 time‐site units) in Poland beginning from the Middle Ages onward. The most frequently found was the goshawk Accipiter gentilis followed by the white‐tailed eagle Haliaeetus albicilla and the sparrowhawk Accipiter nisus. Clues of possible hawking include high status of sites, occurrence of species used in falconry outside their natural ranges, preponderance of females, the presence of sub‐adult specimens and others. It is suggested that surface damage observed on prey bones done by the hawks' beaks and claws may be an extra evidence of hawking. The present study strongly supports the notion that hawking was a very popular activity in medieval Poland. In the future, medieval bone assemblages should always be checked for clues of hawking. The present study may also be used as a source of raw data for other analyses because it includes detailed information on birds of prey from all zooarchaeological reports published so far in Poland. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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