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Urban sprawl has a major impact on the environment, public health and the socio-economic evolution of cities. The causes are numerous, being mainly related to the generalized use of the automobile in modern cities. Urban sprawl has been especially relevant in US cities since the 1950s, rapidly spreading to other cities in the rest of the world. This paper studies the case of Spain using recent data. Spanish cities have grown rapidly over the 90s and 2000s. The country has completed the process of urbanization and has suffered the effects of a major real estate bubble. In this context, we are interested in measuring and explaining where and why urban sprawl has appeared in Spanish cities. Digital mapping carried out around the year 2000 providing full coverage of Spain is used to calculate an Urban Sprawl Index. It is applied to all urban areas and municipalities throughout the country, providing an objective, comparable measurement of sprawl and identifying which areas are most affected by this phenomenon. A second stage of analysis is conducted in an attempt to explain the causes of the differences in sprawl among Spanish cities with a regression model based on the literature. We have found that the cases most affected by sprawl are the latest urban developments on the Mediterranean coast as well as certain areas in the vicinity of large cities: the mountains to the north of Madrid and the coastline near Barcelona and Valencia. In some cases, urban sprawl is starting to become a problem for the environment and urban sustainability, with important consequences for the future evolution of the affected cities.  相似文献   
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KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is today the KwaZulu-Natal province of South Africa. These sites have yielded, among other remains, abundant evidence of ivory and ivory working dating to the seventh–tenth centuries ad, pre-dating by approximately 200 years the better-known ivory artefacts from sites in the Limpopo River Valley and surrounding regions. We report the results of carbon, nitrogen and strontium isotope analysis to explore the origins and procurement of this ivory, in combination with Zooarchaeology by Mass Spectrometry (ZooMS) to identify the species of animals from which it was derived. All of the ivory studied using ZooMS was elephant, despite the presence of hippopotamus remains on all three sites. Some ivory was probably obtained from elephant herds that lived close to the sites, in the densely wooded river valleys favoured by both elephants and early farmers. Other material came from savannah environments further afield. Ivory found at these three sites was drawn from different catchments, implying a degree of landscape/resource partitioning even at this early stage. These communities clearly invested substantial effort in obtaining ivory from across the region, which speaks to the importance of this commodity in the economy of the time. We suggest that some ivory items were for local use, but that some may have been intended for more distant markets via Indian Ocean trade.  相似文献   
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The 2017 Foreign Policy White Paper emphasises the importance of ‘maximising’ Australia’s power and influence. However, the White Paper and much of the commentary on Australian foreign policy do not clearly conceptualise ‘power’ or indicate how it ought to be increased. The Lowy Institute’s recent Asia Power Index implies one possible strategy via its resource-based approach to measuring power. We outline a different approach and argue that power should be conceptualised and evaluated as a specific relationship causing behavioural change, rather than as a general attribute of its wielder. To complement the Lowy Institute’s carefully catalogued database, and facilitate a more focused conversation about maximising power and influence in Australian foreign policy, we offer a typology identifying five pathways through which states can translate their material and non-material resources into outcomes that serve the national interest.  相似文献   
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Current research themes relating to prehistoric Central Asian pastoralism are discussed, and the Neolithic to Bronze archaeological sequence in Kazakhstan is briefly outlined. The results of new faunal analyses of six later Bronze Age sites in Central and Northern Kazakhstan are presented. These studies are based upon the analysis of 63,529 bone fragments, of which 27,023 were identifiable to species and element. These assemblages are compared with 16 other sites in Central and Northern Kazakhstan, and the Trans-Ural region. The herd structures at the final Bronze Age site of Kent are discussed in detail. Analyses of absorbed lipid residues from four sites are also presented. In total, 140 pottery sherds were analysed, of which 73 provided sufficient residues for stable isotope ratio determinations. It is concluded that species proportions are highly variable regionally. Cattle are most prevalent in the forest steppe zone, whilst caprines become more common in semi-arid steppe regions. Proportions of horse are particularly variable, even within environmentally similar areas. Lipid residue results indicate the high prevalence of ruminant dairy products in pottery vessels, whilst faunal data from Kent suggests that cattle husbandry might have been particularly focussed on milk, in comparison with sheep and goats. The significance of horses within prehistoric pastoralism is discussed.  相似文献   
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