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SCOTT KIRSCH 《对极》2012,44(3):1042-1049
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This paper reviews the evolution of land use and mangrove forest management in a coastal commune in Central Vietnam from its early period of environmentally sound management under a common property regime, through State and cooperative management, to individual household allocation under the economic reforms of the 1990s. It analyses in particular the introduction of shrimp culture and its environmental and socioeconomic consequences. The case study demonstrates that, while opening up many economic opportunities, Vietnam's economic reforms have had uneven impacts on income inequality. Like many cases in Asia and Latin America, the disruption of common property resources – through the introduction of aquaculture as a livelihood opportunity and producer of an export crop – leaves farmers indebted and natural resources polluted. But, ironically, it was the financially better‐off aquaculture farmers, who had more capacity for risk‐taking and investing, who ended up most indebted, in comparison with poorer farmers who had already sold their ponds. The latter were less integrated into the market economy and relied more on marine product collection. This paper suggests that attention to local contexts and histories can contribute to a better understanding of the causes and consequences of environment‐poverty interfaces.  相似文献   
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Golf is a recreation industry particularly sensitive to climate, yet the potential implications of climate change for the industry remain largely unexamined. This study presents findings of the first known impact assessment to compare the regional impacts of projected changes in the climate on the golf industry in Canada (or internationally). Empirical relationships between daily rounds played and four weather variables were defined through multiple regression analysis and then used to examine the potential impacts of two climate change scenarios on the length of the golf season and the number of rounds played in three regions of Canada (West Coast, Great Lakes, East Coast). Regionally, the West Coast region was projected to benefit the least from projected climate change, as golf courses that are currently open year round experienced only slight projected increases in rounds played in the 2020s and 2050s. Golf courses in the Great Lakes region could experience a 10- to 51-day longer average golf season and a 21 percent to 3 percent increase in rounds as early as the 2020s, and an even more pronounced increase in the 2050s. East Coast golf courses were projected to benefit the most under both climate change scenarios, experiencing larger gains in average operating seasons (25 to 45 days in the 2020s) and a 40 percent to 48 percent increase in rounds played by as early as the 2020s.  相似文献   
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Previous stable isotope studies for shellfish collected in waters surrounding the Palauan archipelago (north‐western tropical Pacific) have demonstrated that various local shellfish taxa may be reliable recorders of their ambient water temperatures from modern and archaeological contexts. In this study, we analysed stable oxygen isotope (δ18O) signatures of Tridacna crocea from the archaeological site of Metuker ra Bisech (B:IR‐2:24) to reconstruct average nearshore sea‐surface temperatures (SST) from two components dated to c.560 and 120 calBP. Modern shellfish samples and environmental data were collected from intertidal zones on nearby Orrak Island to provide a modern analogue. These shells were tested using X‐ray diffraction to ensure no secondary recrystallisation of the aragonitic structure. Uncontaminated samples were measured for δ18O to pair with recorded SST. The most appropriate oxygen isotope‐to‐SST conversion formula was then applied to δ18O signatures from archaeological T. crocea to estimate SST averages. The results of this study indicate that T. crocea accurately records ambient SST and is a good proxy for palaeotemperature reconstruction. Our results were compared to previous isotopic studies on Palauan taxa collected to identify regional changes to SST through time, thus allowing for comparisons between human subsistence practices, resource availability and past palaeoenvironments.  相似文献   
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The UK government's consideration of whether to replace Trident evokes past controversies about the bomb including occasions when the Labour Party advocated unilateral renunciation of British nuclear weapons. Out of office, fierce debate engulfed the party, fuelled by, and in turn fuelling, intra-party conflict. In power, while Labour governments took different decisions on key defence issues to their Conservative counterparts, they nevertheless ensured that the UK remained a nuclear weapons state. Labour also ensured the habits of secrecy in nuclear decision-making were ingrained, though these were challenged by the current government. This article examines the development of Labour's approach to nuclear weapons since 1945. Particular attention is given to the 1980s as members of the current cabinet will have clear recollections of campaigning on an anti-nuclear policy in the 1980s. The Blair government has embarked on public debate ahead of a formal decision and should the issue of Britain's nuclear status become embroiled in a political battle over the leadership succession, anti-nuclear sentiment may re-emerge. Yet if the past is guide to the future, the history of Labour governments suggests that the real debate will be about what replaces Trident not whether it is replaced.  相似文献   
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Australia's metropolitan cities have undergone significant social, economic and demographic change over the past several decades. In terms of socio‐economic advantage and disadvantage these changes, which are often associated with globalisation, wider economic and technological restructuring, the changing demographics of the population and shifts in public policy are not evenly dispersed across cities, but represent a range of often contrasting outcomes. The current paper develops a typology of socio‐economic advantage and disadvantage for locations across Australian metropolitan cities. More specifically, the paper takes a range of Australian Bureau of Statistics data and uses a model‐based approach with clustering of data represented by a parameterised Gaussian mixture model and discriminant analysis utilised to consider the differences between the clusters. These clusters form the basis of a typology representing the range of socio‐economic and demographic outcomes at the local community level.  相似文献   
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This paper presents oxygen, strontium and neodymium isotopic analysis from a series of Late Bronze Age glasses from Egypt and Mesopotamia. It was found that oxygen and neodymium isotopes alone cannot readily distinguish between glasses from the various sites. However, combined Sr and Nd isotope analysis separate the data into three groups: an Egyptian group with relatively low Sr and Nd ratios; a Late Bronze Age (LBA) Nuzi group with high Sr and low Nd ratios; and an intermediate Sr and high Nd ratio grouping of glasses from Tell Brak. These findings suggest that most of the glass from Nuzi and Tell Brak had different raw materials and hence the glass was probably produced at different manufacturing sites. However, one glass ingot found at Tell Brak (TB1) appears to have Nuzi‐type Sr–Nd characteristics. This is the first positive identification of multiple production sites in LBA Mesopotamia and an exceptional example of a glass that may have been exchanged from one LBA site to another.  相似文献   
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