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Community-based approaches are pursued in recognition of the need for place-based responses to environmental change that integrate local understandings of risk and vulnerability. Yet the potential for fair adaptation is intimately linked to how variations in perceptions of environmental change and risk are treated. There is, however, little empirical evidence of the extent and nature of variations in risk perception in and between multiple community settings. Here, we rely on data from 231 semi-structured interviews conducted in nine communities in Western Province, Solomon Islands, to statistically model different perceptions of risk and change within and between communities. Overall, people were found to be less likely to perceive environmental changes in the marine environment than they were for terrestrial systems. The distance to the nearest market town (which may be a proxy for exposure to commercial logging and degree of involvement with the market economy), and gender had the greatest overall statistical effects on perceptions of risk. Yet, we also find that significant environmental change is underreported in communities, while variations in perception are not always easily related to commonly assumed fault lines of vulnerability. The findings suggest that there is an urgent need for methods that engage with the drivers of perceptions as part of community-based approaches. In particular, it is important to explicitly account for place, complexity and diversity of environmental risk perceptions, and we reinforce calls to engage seriously with underlying questions of power, culture, identity and practice that influence adaptive capacity and risk perception.

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加拉帕戈斯海参捕捞危机是由于大量的移民涌入、激烈的经济竞争以及软弱无力的管理机构所造成的一个典型例子.短时期内,海参捕捞已经成为加拉帕戈斯地区最有煽动性的争议问题.就对新的海洋资源进行高效捕捞来说关键因素并不是渔民本身,而是新的捕捞技术、银行贷款和水产市场.这说明造成每年海参捕捞危机的原因非常复杂而不仅仅因为不断增多的渔民加大了海参的捕捞量.本文通过人口普查数据和渔民注册登记数据分析了该群岛人口的增长情况.还通过一项民意调查来确定人们对海参捕捞和有关规定的态度.定性的采访揭示了海参繁荣的历史,同时海参监测信息也提供了年海参捕捞量的估计值.  相似文献   
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Microbiological characteristics in a zero-valent iron reactive barrier   总被引:6,自引:0,他引:6  
Zero-valent iron (Fe0)-based permeable reactive barriertreatment has been generating great interest for passivegroundwater remediation, yet few studies have paid particularattention to the microbial activity and characteristics withinand in the vicinity of the Fe0-barrier matrix. The presentstudy was undertaken to evaluate the microbial population andcommunity composition in the reducing zone of influence byFe0 corrosion in the barrier at the Oak Ridge Y-12 Plantsite. Both phospholipid fatty acids and DNA analyses were usedto determine the total microbial population and microbialfunctional groups, including sulfate-reducing bacteria,denitrifying bacteria, and methanogens, in groundwater andsoil/iron core samples. A diverse microbial community wasidentified in the strongly reducing Fe0 environment despitea relatively high pH condition within the Fe0 barrier (up topH 10). In comparison with those found in the backgroundsoil/groundwater samples, the enhanced microbial populationranged from 1 to 3 orders of magnitude and appeared to increase from upgradient of the barrier to downgradient soil. Inaddition, microbial community composition appeared to change overtime, and the bacterial types of microorganismsincreased consistently as the barrier aged. DNA analysisindicated the presence of sulfate-reducing and denitrifyingbacteria in the barrier and its surrounding soil. However, theactivity of methanogens was found to be relatively low,presumably as a result of the competition by sulfate/metal-reducing bacteria and denitrifying bacteria because of the unlimited availability of sulfate and nitrate in the site groundwater. Results of this study provide evidenceof a diverse microbial population within and in the vicinity ofthe iron barrier, although the important roles of microbial activity, either beneficially or detrimentally, on the longevityand enduring efficiency of the Fe0 barriers are yet to be evaluated.  相似文献   
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To assess contaminant concentrations in the Firth of Clyde in relation to the former sewage sludge dump site at Garroch Head, and investigate any temporal changes, fish have been sampled annually since 1992 and sediment since 1999. In addition, a further four locations in the Clyde (Holy Loch, Hunterston, Skelmorlie and Irvine Bay) have been sampled for fish and sediment since 1999. Chlorobiphenyls (CBs) were measured in fish samples and polycyclic aromatic hydrocarbons (PAHs) and CBs in sediment. Since sampling was initiated the concentration for the summation operatorICES7 CBs in fish liver has been consistently >500 microg kg(-1) lipid weight at Garroch Head and the other Clyde sites and lower at the reference sites (Pladda, Colonsay, Broad Bay). Although the lowest CB concentrations of the eleven year period in plaice liver from Garroch Head were found in 2002, CB concentrations were found not to have decreased significantly since sewage sludge dumping ceased in 1998. However, a change in CB profile was observed with fish liver collected between 1992 and 1998 from Garroch Head showing a lower proportion of the less chlorinated CBs compared to the 1999-2002 liver samples. Highest CB and PAH concentrations in sediment were found at Garroch Head and Holy Loch with concentrations at these sites being significantly higher than at all other sites.  相似文献   
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Lead has been found to depress the immune system in animal studies at levels far below those responsible for overt toxicity. Literature studies in animal systems most clearly showed an effect of lead on response to a specific immunogenic stimulus. Data are sparse concerning the effects of lead on the immune system in the human population at greatest risk for exposure-children up to six years of age. This portion of the Phase I study reports concentrations of IgG, IgM, IgA, and IgE, as well as antibody titers to the specific antigenic stimuli provided by the vaccines against diphtheria, tetanus, and Rubella. The study population consisted of a group of 193 children, ages 9 months to 6 years, who participate in the WIC (Women, Infants and Children) and Lead Poisoning Prevention Programs in the urban area of Springfield-Greene County Missouri. Blood lead levels ranged from 1 to 50 g dL–1. Total Ig levels were determined and the data were analysed. No consistent significant differences were observed among the risk categories in the five age groups examined. A single Ig class in each of three age groups showed apparent significant differences among the various risk categories, but these differences were not correlated with blood lead. An analysis of specific antibody titers to diphtheria, tetanus, and Rubella was performed. Regression analyses of current data in Phase I of this study suggest a detrimental effect of lead on the antibody titres to diphtheria and Rubella.  相似文献   
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The objective of this study was to detect fetal HLA-DQα gene sequences in maternal blood. HLA-DQα genotypes of 70 pregnant women and their partners were determined for type A1. We specifically sought couples where the father, but not the mother, had genotype A1. In 12 women, maternal blood samples were flow-sorted. Candidate fetal cells were isolated and amplified by using PCR primers specific for a paternal HLA-DQα A1 allele. Fetal HLA-DQα A1 genotype was predicted from sorted cells; amniocytes or cheek swabs were used for confirmation. Six of twelve sorted samples had amplification products indicating the presence of the HLA-DQα A1 allele; 6/12 did not. Prediction of the fetal genotype was 100 per cent correct, as determined by subsequent amplification of amniocytes or cheek swabs. We conclude that paternally inherited uniquely fetal HLA-DQα gene sequences can be identified in maternal blood. This system permits the identification of fetal cells independent of fetal gender, and has the potential for non-invasive prenatal diagnosis of paternally inherited conditions.  相似文献   
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The effects of in situ chemical oxidation (ISCO) on biological processes, as reported in the literature, were researched to determine if coupling ISCO with in situ bioremediation could be achieved in field and laboratory experiments. Literature was compiled concerning the effect of ISCO on microbial communities following addition of a chemical oxidant at a range of concentrations designed to treat a variety of subsurface contaminants. The results indicate that although microbial communities may potentially be adversely affected by chemical oxidation in the short term, a rebound of microbial biomass and/or bioremediation activity can be expected. Successfully coupling ISCO with bioremediation in field applications may be a cost‐effective method of achieving risk‐based site remediation goals. © 2006 Wiley Periodicals, Inc.  相似文献   
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