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881.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years, the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences of development plans are seldom considered). Some international conservation organizations are testing promising new approaches to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources, they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major role in the design and implementation of any fishing management actions.  相似文献   
882.
从江苏省环境安全形势出发,借鉴“压力-状态-响应”(PSR)模型的框架思路,构建了环境安全度量的层次指标体系。从环境安全的压力、状态、响应3个方面确定相应的指数及对应的评估指标,通过基于德尔斐法的层次分析法确定权重,计算环境安全综合指数,并建立环境安全等级划分标准。应用建立的环境安全评估体系,对2006-2012年江苏省环境安全进行了评估。结果表明:2006-2012年,全省环境安全综合指数呈明显下降趋势,安全等级由中警状态好转为预警状态,江苏省环境安全形势不断改善。但2012年以来,大气灰霾、酸雨等复合型污染有所加重,环境安全接近中警状态,全省环境安全形势亟需进一步采取措施进行有效保障。  相似文献   
883.
在当前保障性住房供给与需求矛盾不断加深的背景下,研究保障对象对保障性住房的租赁或购买的需求特征及其关键影响因素,具有较强的必要性与现实意义。本文通过问卷调查方式获取城市中心城区受保障对象的需求特征数据,从保障对象住房需求的视角,分析影响保障性住房租赁或购买选择的相关因素。文中构建了Logit模型,并检验各因素对保障性住房租购选择的影响关系及强度。结果显示:(1)住区环境、个体特征、家庭特征、住房特征等四大类因素对保障性住房租购选择产生显著的影响;(2)住区环境中,教育资源、交通配套设施等是影响保障性住房租购选择的关键指标,这些关键指标的改善,将会使保障对象更倾向于购买保障房而不是租赁;(3)个体特征中,性别与年龄对保障性住房租购选择影响最大,相比男性、年轻人,女性、年长者更倾向于购买保障性住房而不是租赁;(4)家庭特征方面,人口数量多、经济收入高等特征的家庭更愿意选择购买保障房,但家庭人口数量的影响大于家庭经济收入;(5)住房特征中,居住稳定性对保障性住房租购选择影响最大,其次是保障性住房准入政策合理性、住房面积及户型,这些因素的改善,都将提高保障对象对保障性住房做出购买的决策。因此,提供多形式、多条件的保障性住房,才能满足不同保障对象的租赁或购买的需求。设置合理的保障性住房准入条件,构建科学合理规范的保障性住房供给标准和住房保障运行机制,才能使迫切需要租购保障房的家庭从中受益。  相似文献   
884.
以星云湖流域自然人文环境特征、主要生态环境问题为出发点,结合景观生态学原理方法、熵值法和GIS空间分析技术,实现星云湖流域生态安全的空间分异格局及优化。选取海拔高程、坡度、土壤侵蚀强度、地质灾害易发性、土地覆被(利用方式和植被覆盖度)、人口密度、距自然保护区距离、距离建设用地和距水源距离等因素为阻力因子叠加生成综合阻力要素,根据GIS空间成本距离分析原理,引用最小累积阻力模型识别构建流域生态廊道和生态节点,进一步规划优化流域生态功能网络的结构和功能。研究表明:(1)从各安全等级面积比例和平均生态安全指数角度,星云湖流域中度安全占流域总面积的45.81%,高度安全为25.24%,较低安全为21.05%,不安全占7.9%,平均生态安全指数为2.95,流域生态安全总体处于中度安全,生态系统健康一般,但部分地区生态安全性较低,主要分布在南部、东部和北部地区,应重视这些区域的生态保护和建设;同时,坡度、水土流失因子和水资源(自然环境要素)、土地利用格局和距离建设用地(人类活动干扰要素)等因素是流域生态安全格局形成的主要因子;(2)识别规划了中枢生态源、核心型生态源斑块、一般生态源、多种级别的生态廊道和生态节点或战略点等构成的具有结构性和层次性的流域生态安全网络格局,对不同层次和结构的生态源、生态廊道和生态节点或战略点进行针对性建设保护,将有效提升流域生态系统的功能价值性和系统的完整性,进而加强流域生态稳定安全。  相似文献   
885.
In this paper, we document and analyse the recent decline (2007–2013) in domestic water consumption in Barcelona. The postulates of ecological modernisation and market environmentalism celebrate these declines as an example of sustainable development, thanks to the combination of more efficient technologies and economic incentives. However, these interpretations ignore the new framework of social relations introduced by technologies and markets and take environmental improvements as homogeneous and universal regardless of distributional issues. Therefore, it would be perfectly possible to achieve optimal environmental situations in the context of deteriorating social conditions, particularly in terms of access to basic resources by the most disadvantaged. We explored the relationships between declining domestic water consumption and the uneven impact of the economic crisis on Barcelona’s urban geography. We found that the alleged increase in environmental sustainability that follows decline in resource use translates into highly uneven social impacts in terms of both accessibility and consumption. These results show that water flows have profound political dimensions and that water justice in terms of distributional costs and benefits but also in terms of recognition and participation of the less well-off should be a fundamental component of future urban water policies in this area.  相似文献   
886.
This paper’s purpose is to predict China’s uranium resources demand from 2016 to 2030 based on experimental modeling. In addition, we discuss the future supply structure of China’s uranium resources by analyzing the domestic and foreign supply capacity of China’s uranium resources. According the forecast results, Chinese uranium resource demand will reach 21385 tU in 2030 under a medium scenario. Due to the poor endowment of uranium resources, China’s domestic uranium production will increase slowly. It can be calculated that the total demand of uranium resources in China during 2016–2030 will be 216581 tU, the cumulative production of domestic production will be 37900 tU, the overseas production will be 41950 tU, and the international market purchases will be 130574 tU. Hence, the cumulative degree of dependence on foreign resources is approximately 80%. China’s foreign dependence on uranium will be greater than for oil, and the situation will become extremely serious. Therefore, we put forward several suggestions to ensure the supply of China’s uranium resources: (1) strengthening mineral exploration and increasing domestic production, (2) actively operating the “going out” strategy, (3) enhancing the enterprise competition ability, and (4) establishing uranium resource reserves. By these means, China could efficiently guarantee the domestic uranium resource security and respond to the competition of India’s uranium resources demand increased.  相似文献   
887.
This study examines the effects of relocating the Flint Farmers’ Market, a large and successful market in the medium-sized legacy city of Flint, Michigan. Over the course of a year, market patrons and vendors were surveyed to explore questions about the scale of the market, patron demographics, reasons for visiting the market, seasonal variations in outcomes, and healthy food access. The results indicate that the relocated, downtown market is successful in large part because it satisfies multiple needs – it provides access to fresh, local produce; it provides lunch options for downtown workers and students; and it serves as a community gathering space. The study further demonstrates that farmers’ markets in legacy cities can serve a large region, attract diverse customers, and remain sustainable year-round, even in northern climates. These findings should be of interest to planners, policy-makers, and market managers who are considering opening or relocating a farmers’ market as a means of supporting community health, well-being, and economic development.  相似文献   
888.
Ekblom A 《Ambio》2012,41(5):479-489
A sustainable livelihood framework is used to analyse livelihood security, vulnerability and resilience in the village of Chibuene, Vilanculos, southern Mozambique from a historical and contemporary perspective. Interviews, assessments, archaeology, palaeoecology and written sources are used to address tangible and intangible aspects of livelihood security. The analysis shows that livelihood strategies for building resilience, diversification of resource use, social networks and trade, have long historical continuities. Vulnerability is contingent on historical processes as long-term socio-environmental insecurity and resultant biodiversity loss. These contingencies affect the social capacity to cope with vulnerability in the present. The study concludes that contingency and the extent and strength of social networks should be added as a factor in livelihood assessments. Furthermore, policies for mitigating vulnerability must build on the reality of environmental insecurity, and strengthen local structures that diversify and spread risk.  相似文献   
889.
Marincioni F  Fraboni R 《Disasters》2012,36(2):291-315
Besides offering teaching and research services, schools and universities also must provide for the safety and security of their employees, students, and visitors. This paper describes emergency preparedness in a sample of Italian universities. In particular it examines risk perception within a specific professional category (university safety and security officers) in a specific cultural context (Italy). In addition, it discusses the transposition and implementation in a European Union (EU) member state of EU Council Directive 89/391/EEC of 12 June 1989, on the introduction of measures to encourage improvements in the safety and health of workers. The findings highlight heterogeneous and fragmented emergency management models within the Italian university system, underlining the need for a stricter framework of standardised safety protocols and emergency management guidelines. The study also points out that enhancing emergency planning and preparedness in Italian universities entails increasing safety leadership, employee engagement and individual responsibility for safety and security; essentially, it necessitates improving the culture of risk prevention.  相似文献   
890.
野战弹药环境安全的灰色模糊综合评判   总被引:1,自引:1,他引:0  
战场环境安全评价是对野战弹药实施合理防护的前提。将灰色模糊数学理论应用于“弹药-野战环境”系统的安全评价,通过分析影响野战弹药安全的环境因素,建立了系统综合评价指标体系,在此基础上进行了系统综合评价并得到了满意的效果。  相似文献   
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