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991.
Abstract

Environmental justice laws protect certain populations against discriminatory actions that may result from a myriad of enterprises, including transportation activities. Previous environmental equity studies examining the effects of transportation-engendered externalities have been criticized on several points, including (1) that the choice of a reference population for comparison to the criterion variable may influence the outcome of research results and (2) that the selection and use of inappropriate methodologies intended to identify and characterize populations may foreordain research outcomes. This article examines the potentially confounding effects of selected spatial scale and population assignment strategies as applied to a study of excessive noise levels at a large Midwestern airport, finding that reported outcomes can vary significantly as a function of methodological choices.  相似文献   
992.
993.

This paper investigates the historical relationship between the development of marine-based tourism and representations of marine space. Over the past 100 years, the Caribbean Sea has been transformed from a transportation surface connecting exotic ports of call into a commodity itself. Imagined by early travelers as a two-dimensional space to be crossed, the Caribbean has became part of a new tropical marine aesthetic, a three-dimensional spectacle to be actively consumed and conserved. These changing representations of the marine environment as a space of consumption have been paralleled by changes in the relationships between marine and terrestrial political economies. As marine-based tourism has intensified, the balance of power among coastal resource users has shifted. The increasingly conflictive consequences of this shift are illustrated by the case of Soufrière in St. Lucia where new uses of marine space have re-configured social and economic relationships. Soufrière's coastal economy has been transformed and its marine space increasingly politicized as competing representations of the sea have been used to assert conflicting claims to resource access. This paper attempts to elucidate the power of these representations by investigating their historical relationship to the changing role of the Caribbean Sea in the international tourism industry.  相似文献   
994.
The grassroots environmental movement often protests locally unwanted land uses. Many grassroots groups have, however, expanded their agenda to the scale of environmental justice. Explanations for this scale transformation include historical circumstances, individuals' radicalization through activism, and the growth of environmental justice networks. This case study, grassroots environmentalists' opposition to a proposed electricity transmission line in Monroe County, WV, explores another explanation: appeals for environmental justice are also a strategic response to siting regulatory procedures. With concepts emerging from the political geography of scale, I interpret the Monroe Countians' efforts and show how their strategies link the grassroots scale with that of environmental justice.  相似文献   
995.
This article addresses the need to better understand the complex interactions between climate, human activities, vegetation responses, and surface ozone so that more informed air-quality policy recommendations can be made. The impacts of intraseasonal climate variations on ozone levels in Tucson, Arizona from April through September of 1995 to 1998 are determined by relating variations in ozone levels to variations in atmospheric conditions and emissions of ozone's precursor chemicals, volatile organic compounds (VOCs) and nitrogen oxides (NOx), and by determining month-specific atmospheric conditions that are conducive to elevated ozone levels. Results show that the transport of ozone and its precursor chemicals within the Tucson area causes the highest ozone levels to be measured at a downwind monitor. The highest ozone levels occur in August, due in part to the presence of the North American monsoon. Atmospheric conditions conducive to elevated ozone concentrations differ substantially between the arid foresummer (May and June) and the core monsoon months ( July and August). Transport of pollution from Phoenix may have a substantial impact on elevated ozone concentrations during April, May, and June, while El Paso/Ciudad Juarez –derived pollution may contribute significantly to elevated ozone concentrations in August and September. Two broad policy implications derive from this work. Regional pollutant transport, both within the U.S. and between the U.S. and Mexico, is a potential issue that needs to be examined more intensively in future studies. In addition, spatiotemporal variations in sensitivities of ozone production require the adoption of both NOx and VOC control measures to reduce ozone levels in the Tucson area.  相似文献   
996.
Recognized for years as a major environmental disruption, El Niño generated intense public interest in 1982–1983. During its last occurrence, this phenomenon, which develops in the tropical Pacific and usually affects rimlands of the Pacific basin, exceeded its boundaries and its effects were transmitted to continental North America, Europe, Africa and East Asia. Notwithstanding its vast areal extent, the interest of geographers in El Niño events, past and recent, has been comparatively less than that demonstrated by natural scientists and ecologists: little has been accomplished to place these climatic-ecological crises within global perspective. Lessons from El Niño include the acknowledgement of new concepts of climatic transitivity, ocean dynamics and energy exchanges that must find a place within the conceptual wealth of geography if this science intends to keep up with the rapid progress of other geosciences.  相似文献   
997.
《Urban geography》2013,34(7):694-725
This article explores the possibilities for a political ecology of gentrification. Gentrification research, while firmly rooted in materialist social science, has not yet broadened its interests to consider ecological aspects of, or the role in gentrification of, discourses, social movements, and state policies of the environment. Understanding the political ecologies of gentrification involves recognizing the ways in which material relations and uneven resource consumption, concepts of nature, and the politics of urban environmental management affect gentrification processes. By synthesizing diverse literatures in urban studies, political ecology, urban environmental governance, consumption studies, and gentrification, this study argues that Vancouver, British Columbia represents a well-developed urban crucible for the new political ecologies of gentrification in North America. New developments in Vancouver increasingly contribute to gentrification using languages of sustainability and green consumption in a process of ecological gentrification.  相似文献   
998.
海洋生态修复是遏制海洋生态系统退化的重要途径,受到全球越来越多学者的关注。本研究以科学引文索引(Science Citation Index Expanded,SCIE)数据库为数据源,采用文献计量统计分析方法,结合VOSviewer知识图谱可视化分析软件,定量分析了1980—2019年国际上在海洋生态修复领域发表的相关文献,梳理了近40年来该领域研究的发展脉络、前沿热点和未来方向。结果表明,近40年间,海洋生态修复领域的发文数量随时间呈上升趋势,尤其2000年后增长速度加快,以北美洲、大洋洲、欧洲国家居多,其中美国占绝对领先地位。海洋生态修复领域涉及的学科主要有环境科学、生态学、海洋及淡水生物学等,Journal of Coastal Research、Restoration Ecology、Ecological Engineering和Estuarine,Coastal and Shelf Science是该领域的主要发文期刊。当前海洋生态修复研究热点主要包括植被恢复、海洋生物种群恢复、滨海湿地修复与生物地球化学、气候变化与生态系统管理等主题,其中关于缓解和适应气候变化、生态系统的自然恢复途径、生态系统服务功能提升等方面的研究愈来愈受到关注,是未来一段时间内海洋生态修复领域的研究热点。随着我国《国民经济和社会发展第十四个五年规划》拉开序幕以及海洋生态文明建设不断深化,我国海洋生态修复研究将驶入快车道,建议在应对气候变化的海洋生态修复、区域性海洋生态系统修复规划、海洋生态退化机理与修复关键技术、适应性管理等方面加强研究和探索。  相似文献   
999.
暖水珊瑚礁生态系统是热带海域最具生物多样性和代表性的生态系统之一。本研究分析了全球变化背景下暖水珊瑚礁生态系统的变化和风险,开展了受损暖水珊瑚礁生态系统退化和消失的致灾因子归因分析,综述了暖水珊瑚礁生态系统的适应性与修复技术研究。分析表明:①过去几十年来,暖水珊瑚礁生态系统快速退化,包括大面积白化和死亡、多样性明显减少和生态功能显著衰退,主要归因于海洋升温与人类活动等致灾因子的影响;②在温室气体高排放浓度情景下(RCP 8.5),相比工业革命前,到本世纪中叶,南海升温将可能远超过2℃,这表明南海暖水珊瑚礁生态系统正在逼近其气候临界点,即全球升温高于2℃时,90%~99%以上的暖水珊瑚将消失;③1980年代以来,海洋升温、海洋热浪和强热带气旋等海洋气候变化致灾因子对南海暖水珊瑚的危害性(影响的强度、范围和时间)明显增加,对暖水珊瑚礁生态系统产生了严重的影响;与此同时,近岸海域的过度或破坏性捕捞、采挖和潜水等人类活动,对暖水珊瑚造成了严重损害,增加了暖水珊瑚的气候脆弱性,而这种人类活动既是局部的,也是全球性的现象,使得暖水珊瑚更难以适应全球变暖的影响。分析还表明,为了增强暖水珊瑚适应气候与环境变化的恢复力(韧性),人们开展了诸多受损珊瑚礁生态系统的适应性与修复研究,但主要是采用无性繁殖或结合人工基质的修复方式,而应用有性繁殖技术恢复受损珊瑚礁的方式仍较少;最近,暖水珊瑚耐热的基因适应性研究取得了重要进展,为暖水珊瑚适应全球变暖提供了一种新的途径。本研究最后探讨了中国受损珊瑚礁生态系统的修复问题与对策。  相似文献   
1000.
苯酚对海洋生态环境具有较大的威胁,从红树林根际土壤中分离获得对环境具有高适应性的高效芳烃降解菌具有重要的意义。本研究对北部湾红树林根际土壤中的苯酚降解菌进行富集培养,经过分离纯化得到30株菌株,筛选得到5株菌株FGYS1、FGYS7、FGYS11、FGYB1和FGYB5,可耐受70 g/L NaCl的高盐环境,最高可降解1 500 mg/L的苯酚。采用形态观察、BOX-PCR菌种多样性分析、16S rRNA序列分析等方法对菌株进行鉴定,均为假单胞菌属(Pseudomonas)。菌株FGYS1、FGYS7和FGYS11为同一种假单胞菌,与Pseudomonas extremaustralis 14-3T和Pseudomonas meridiana CMS 38~T的16S rRNA序列相似性分别达到99.71%和99.64%。菌株FGYB1和FGYB5为同一种假单胞菌,分别与Pseudomonas veronii DSM 11331~T和Pseudomonas extremaustralis 14-3~T的16S rRNA序列相似性均达到99.64%。16S rRNA序列的系统发育树分析表明菌株FGYS1、FGYS7、FGYS11、FGYB1和FGYB5在进化上与P. veronii为同一个分支,而与假单胞菌属其他模式菌株的序列进化关系相距较远。菌株FGYS1降解苯酚的适宜温度为25~35℃、适宜pH为4~6、最高耐NaCl含量为60 g/L;菌株FGYB1降解苯酚的适宜温度为25~35℃、适宜pH为4~6、最高耐NaCl含量为100 g/L,两株菌株对pH、温度和盐度的适应范围较广。菌株FGYS1和FGYB1还可以同时降解邻苯二酚、对苯二酚和间苯二酚。本研究分离得到的苯酚降解菌在应对红树林芳烃污染和生态环境修复方面显示了较大的潜力。  相似文献   
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