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151.
Previous soil lead studies in New Orleans focused on the geochemical footprint and its health impacts. This study examines the human geography of race, income, and age in pre-Katrina metropolitan New Orleans within the context of lead accumulation in soils. Sample points of soil lead data (n = 5,467) collected in 1998–2000 were mapped in a geographic information system (GIS), binned into 9 ranges, and queried by (1) 2000 Census racial demographic data, (2) 1999 median household income, and (3) 2000 age data. The absolute population generally declines as lead levels increase except at lead levels from 200–400 to 400–1,000 mg/kg when population increases; the African–American population comprises a disproportionate share of this cohort. The high-lead areas occur in the inner city, home to the largest populations of African-Americans in New Orleans. The mean household income curve indicates that lower economic groups are at risk to higher levels of lead. A total of 44,701 children under the age of 5 years, plus 123,579 children aged 5–17, lived in census block groups containing at least one sample point with over 100 mg/kg lead, and these include 23,124 and 64,064 young people, respectively, who live near at least one point over 400 mg/kg. Lead exposure affects a panoply of outcomes that influence the health and welfare of the community. Unless corrected, children are likely to return to the same or, because of lack of lead-safe practices during renovation, even higher exposure risks than before the flooding of New Orleans.  相似文献   
152.
Abstract:  Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures ( Faith & Walker [1996] , Sarkar et al. [2004] , and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone.  相似文献   
153.
154.
沈北新区土壤中多环芳烃污染特征及源解析   总被引:10,自引:6,他引:4  
采用均匀网格布点法采集沈阳市沈北新区不同土地利用类型101个表层(0~20 cm)土壤样品,开展土壤中美国环保署优先控制的16种多环芳烃(PAHs)的含量空间分布特征、成分谱分析和污染物来源解析研究.结果表明,沈北新区土壤中16种PAHs(ΣPAHs)总含量为123.7~932.5μg·kg~(-1);PAHs组分以3~4环的中、低环组分为主,其中3环PAHs比例最高;ΣPAHs的空间分布特征明显,呈现出由南向北、自东向西逐渐递减的趋势.在研究区域所涉及的5种土地利用类型土壤中,土壤ΣPAHs含量的高值主要集中在城区绿地和人工绿化林地,其次为设施菜地,水稻田和玉米田中ΣPAHs含量相对较低且无明显空间分布差异.利用特征比值分析和因子分析/多元线性回归分析进行土壤中PAHs的污染源解析,初步确定沈北新区表土中PAHs的主要污染源为燃烧源和石油源的混合源,其中,工业燃煤和机动车尾气是PAHs的主要污染源,其贡献率达79.6%,石油泄漏和焦炉排放贡献率约为16.2%,生物质燃料的燃烧贡献率占4.2%.  相似文献   
155.
中国环境保护战略政策70年历史变迁与改革方向   总被引:5,自引:0,他引:5       下载免费PDF全文
系统地回顾了新中国成立70年以来环境保护战略政策的历史变迁,分析其演进脉络、阶段性变化特征和取得的成效,对于制定新时代国家生态环境保护战略政策、全面推进生态文明和"美丽中国"建设具有重大现实意义.以环境保护战略政策历史演进为主线,将新中国成立70年以来的环境保护战略政策历史变迁与发展划分为5个阶段:①非理性战略探索阶段(1949-1971年);②建立环境保护三大政策和八项管理制度的环境保护基本国策(1972-1991年);③强化重点流域、区域污染治理的可持续发展战略(1992-2000年);④控制污染物排放总量、推进生态环境示范创建的环境友好型战略(2001-2012年);⑤推进环境质量改善和"美丽中国"建设的生态文明战略(2013年至今).分析表明,我国基本形成了符合国情且较为完善的环境战略政策体系,在生态文明和环境保护法制与体制改革、生态环境目标责任制、生态环境市场经济政策体系以及多元有效的生态环境治理格局下取得了重大成就,对环境保护事业发展发挥了不可替代的支撑作用,为深入推进生态文明建设和"美丽中国"伟大目标实现提供了重要保障.结合新时代生态文明建设和"美丽中国"建设的目标需求,提出了未来我国生态环境保护战略政策的基本走向、改革目标,指出了管理体制、生态法治、空间管控、市场机制、公众参与、责任考核等六大改革方向.   相似文献   
156.
Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO_2, coarse mode, and accumulation mode(100–500 nm) particles. Through single particle mass spectrometry analysis, five different types of particles(fireworks-metal, ash, dust, organic carbon-sulfate(OC-sulfate), biomass burning) with different size distributions were identified as primary emissions from firework displays. The fireworks-related particles accounted for more than70% of the total analyzed particles during severe firework detonations. The formation of secondary particulate sulfate and nitrate during firework events was investigated on single particle level. An increase of sulfite peak(80SO_3~-) followed by an increase of sulfate peaks(97HSO_4~-+ 96SO_4~-) in the mass spectra during firework displays indicated the aqueous uptake and oxidation of SO_2 on particles. High concentration of gaseous SO_2, high relative humidity and high particle loading likely promoted SO_2 oxidation. Secondary nitrate formed through gas-phase oxidation of NO_2 to nitric acid, followed by the condensation into particles as ammonium nitrate. This study shows that under worm, humid conditions, both primary and secondary aerosols contribute to the particulate air pollution during firework displays.  相似文献   
157.
The Manawatu floods of 2004 have had significant, long-lasting social consequences. This paper draws on findings from a series of detailed surveys of 39 farm households directly affected by the floods and 17 individuals directly involved in managing the flood recovery programme. The nature of the impact on rural families highlights how the 'hollowing out' of rural New Zealand has changed the capacity of rural communities to respond to natural hazards and increased their sense of isolation. In addition, the floods exposed the vulnerability of rural communities. This is shown to have implications for policies designed to build resilience and improve responses to adverse events, including the need to support local, community initiatives on self-reliance and mutual support. Approaches to manage better long-term flood risks should be designed within a context of ongoing rural decline that has compromised the health of both individuals and communities.  相似文献   
158.
Despite the apparent failure of international negotiations and renewed criticism of the accuracy of climate science, responses to climate change continue in households, cities, fields, and meeting rooms. Notions of “doing something about”, or “taking action on” or “mitigating and adapting” to climate change inform practices of carbon trading, restoring native forests, constructing wind turbines, insulating houses, using energy efficient light bulbs, and lobbying politicians for more or less of these actions. These expressions of agency in relation to climate change provide the focus of our enquiry. We found that relationships or social networks linked through local government are building capabilities to respond to climate change. However, the framework of “mitigation–adaptation” will need to be supplemented by a more diverse suite of mental models for making sense of climate change. Use of appropriate languages, cultural reference points, and metaphors embedded in diverse histories of climates and change will assist actors in their networked climate change responses.  相似文献   
159.
天津滨海新区海洋经济可持续发展潜力探讨   总被引:2,自引:1,他引:1  
在对海洋经济可持续发展内涵分析的基础上,构建了以海洋资源承载力、海洋经济发展力和海洋环境质量为主要构成的海洋经济可持续发展指标体系.以天津滨海新区为案例,从环境资源和生态系统稳定的角度对滨海新区海洋经济的可持续发展潜力进行了分析评价,对2006、2008和2015年滨海新区海洋经济发展的可持续综合指数进行了计算,并针对滨海新区海洋经济发展中存在的问题,提出了相应的对策建议.  相似文献   
160.
随着工业化的发展,排向环境中的含酚废水越来越多,由于其具有很强的毒性,目前已经受到国内外广泛关注。因此含酚废水的处理越来越受到人们的关注。本文对含酚废水的来源、危害进行了分析,概述了目前国内处理含酚废水的主要方法,展望了含酚废水处理技术的发展前景。  相似文献   
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