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31.
平衡我国国内旅游消费季节性的途径探讨   总被引:1,自引:0,他引:1  
本针对我国国内旅游消费市场现存季节性的事实,分析了它的几种表现,并提出了平衡这种季节性的主要途径。  相似文献   
32.
The woodchuck, Marmota monax, a burrowing scuirid of eastern North America, was a common food animal of prehistoric peoples. Since the species has a single, brief birthing period all juveniles are at a comparable stage of development at a given time. Widths of the continuously growing incisors, development of the cheek teeth and alveoli, and loss of deciduous teeth have been determined from a sample with known dates of collection. These data are compared to juvenile woodchuck remains from an archaeological site to determine season of kill.  相似文献   
33.
The growth increments of otoliths and vertebrae of plaice (Pleuronectes platessa) derived from a 15th century single depositional event at Raversijde (Belgium) are analysed with the aim of reconstructing (a) the age distribution of the population, (b) the season of capture, and (c) the growth rate. Otoliths and vertebrae give slightly different age distributions but it is possible to arrive at similar seasonality estimations in both structures when information from the literature and our own data from monthly captures of plaice from the North Sea are taken into account. These modern data show that the timing of annulus formation in otoliths and vertebrae is more or less similar. Back‐calculations on vertebrae and otoliths yield similar growth curves. The age distribution, the edge condition of both vertebrae and otoliths, and the growth rate obtained on the material from Raversijde all show that the plaice from the studied assemblage were captured during spring in the southern part of the North Sea. Vertebrae are commonly preserved in archaeological sites whereas otoliths rarely survive. Although they are more difficult to read than otoliths, vertebrae of plaice can be used for growth increment analyses, and the growth rates obtained from vertebrae from archaeological sites can, therefore, be compared in the future to growth data from modern otoliths studied in sea fisheries research. Archaeozoological material predating industrialized fishing since the 19th century can hence serve as a reference in the study of the compensatory response of commercially important species to heavy exploitation. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
34.
An evaluation is given of the value for seasonality studies of incremental growth in the pectoral spines of the Nile catfish Clarias gariepinus. The subfossil spines used for this study are from a Byzantino-Islamic site in Syria, and probably all derive from animals captured on the floodplain during the yearly inundation of the nearby Orontes river, although only 45 per cent of the spines could be recognized as deriving from fish captured during that period. It is believed that the inability to date accurately the season of capture of the other specimens is due to disadvantages inherent in the growth cycle of the fish. For the moment it is possible to determine the season of death only of individuals that were taken during a period of rapid growth.  相似文献   
35.
Cementum banding patterns have been used by archaeozoologists and wildlife managers for a number of decades to assess the season and age at death of mammalian populations. However, the observation and measurement of the nature of cementum banding, especially that of the final band, has proved to be difficult except under conditions of excellent preservation and advanced microscopy. The research presented here details a method for extracting luminance data from the banding patterns of cementum in order to quantify the optical properties of cementum tissue. By doing so, analysis of the relationship between cementum deposition and environmental variables is achieved. We present the results of a digital cementum luminance analysis (DCLA) on a sample of first molars from two species, Ovis aries, Soay and Capra ibex. The results indicate that significant relationships occur between seasonal temperature changes and cementum histology. Furthermore, we show that luminance values can be used to assess the geographical range of genetically similar populations. Our results demonstrate that the study of luminance is a vital tool for the quantitative study of dental cementum for both archaeological and ecological studies. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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