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The condition of a wooden shipwreck varies considerably according to the nature of the site environment. Each marine site exhibits a unique biodeteriogenic potential influenced by prevailing hydrographic factors. The potential rate of degradation of organic archaeological material can be determined by monitoring the diversity and activity of marine organisms and is important in determining if in situ protection is required. To illustrate the deteriogenic potential of marine archaeological sites a cold water site (Langstone Harbour, UK) was compared with a warm water site (Zakynthos, Greece). The warm water site supported a greater diversity and activity of wood-boring crustaceans and molluscs than the cold water site. However, although the mycodiversity at the two sites was different the deteriogenic potential was similar. These results indicated that warm water sites are more hazardous and in situ protection is required during and after excavation.  相似文献   
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In this article I argue that countries exporting fossil fuels, such as Australia, have an obligation to bear some of the costs of the harms caused by the use of those fuels. I argue that there is an analogy between other harmful exports – medical waste, tobacco, unsafe jobs, uranium – and fossil fuels. If this is the case, then current methods for allocating emissions and responsibilities for their harms are inadequate and more complex than they appear. I consider several counter-arguments to this claim, such as that it does not recognise the benefits of coal and that exporters are not really responsible. Finally, I consider some of the consequences of this argument and claim that Australia and other fossil fuel exporters ought to have a higher ‘carbon budget’ if this argument is true and that exporters ought to bear a higher share of the costs of climate harms.  相似文献   
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California and Great Basin archaeologists have long discussed and debated the function of chipped stone crescents found in Terminal Pleistocene and Early Holocene sites in the Far West of North America. Because they are found over a vast area, in sites occupied over a period spanning at least 4,000 years (~12,000–8,000 cal BP), it may be that crescents were used for a variety of purposes. Here we focus on lunate crescents and their strong association with wetland localities (lakes, marshes, estuaries, and islands). We reconsider whether crescents could have been used as transverse projectile points to hunt waterfowl. We also assess the biogeographical legacies of migrating birds to propose that as many as four species of large anatids (tundra swan, greater white-fronted goose, snow goose, Ross’s goose) that now breed in the Canadian High Arctic once bred in the Great Basin and adjacent regions during the Late Pleistocene and Early Holocene. We propose that crescents were used primarily in the taking or processing of geese and swans, some of which may have bred and molted in what are now temperate latitudes. After the Laurentide ice sheet retreated, these four species established High Arctic breeding grounds and no longer bred in the Great Basin. In this scenario, the absence of some populations of molting geese and swans helps explain why crescents fell out of the archaeological record after ~8,000 cal. BP. When crescents were used, Native Americans in the Far West may have had access to millions of large waterfowl.  相似文献   
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