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31.
Advocates of community-based approaches to environmental management argue that by respecting local circumstances, skills, and concerns we may improve the prospects of achieving environmental sustainability; yet, within nation states such as Canada, environmental conditions, management and enforcement costs and capabilities, and power differentials within and among civic and public sectors may result in a highly differentiated capacity for environmental management across different localities and regions. This article draws on insights of political ecology to 1) create a conceptual framework that identifies key elements shaping regional environmental management regimes and to 2) undertake a comparative analysis to assess how elements interact to generate uneven management outcomes. I compare experiences of two Canadian biosphere reserves designated in 2000: Clayoquot Sound, BC; and Redberry Lake, SK. Analysis reveals that differences in governance and institutional capacities in the biosphere reserves are key to explaining uneven local outcomes. Where the public and civic sectors are strong, a robust and publicly vetted form of management will emerge. Where these sectors are weak and land is held as private property, environmental nongovernmental organizations can set the type and level of management, to the exclusion of effective civic and state involvement. This result may improve environmental sustainability but hinder social sustainability of a management regime and raises questions about the efficacy of community-based management.  相似文献   
32.
Impacts of sediments and heavy metals on the biota of streams in the copper-mining district of southwestern Montana were examined by comparing aquatic communities of impacted streams with those of control streams. Control streams were chosen through the use of a technique that identifies similar streams based on similarities in their watershed characteristics. Significant differences between impacted and control sites existed for surface substrate, riparian vegetation, and the number of macroinvertebrate taxa. These results revealed that: (a) chemical and physical habitats at the impacted sites were disrupted, (b) the presence of trout was an inadequate measure of ecological integrity for these sites, and (c) watershed classification based on a combination of mapped terrestrial characteristics provided a reasonable method to select control sites where potential control sites upstream and downstream were unsuitable.  相似文献   
33.
目前我国区域性大气复合污染日益严重,迫切需要明晰的控制技术路线指引。本文尝试将情景分析技术应用于区域复合污染控制方案制定中。建立了包括确定主题、驱动力筛选、驱动力预测、排放量预测和情景构建等步骤的情景设计方法。并利用本文建立的方法,详细介绍了在构建区域大气复合污染压力-状态-响应模型的基础上,利用主要驱动力与压力之间的数学关系,进行驱动力预测、构建基线情景和控制情景的方法。讨论了在制定区域协同控制方案过程中,确定满足区域总量控制目标的分区减排原则,并提出实现区域协同控制区域性大气复合污染的控制目标的分区削减方案情景设计的方法建议。  相似文献   
34.
Aerosol samples were collected at Lin'an, a background site of Yangtze River Delta(YRD).Morphology, size, composition, and mixing state of individual aerosol particles were characterized by transmission electron microscopy(TEM) coupled with energy dispersive X-ray spectroscopy(EDS), and the soluble ions of PM_(1.0) were studied by aerosol mass spectrometer(AMS). The daily average AMS mass concentrations of sulfate, nitrate, and ammonium were about 5.8, 8.6, and 5.6 μg/m~3, respectively. Individual aerosol particles were classified into seven types: S-rich, K-rich, organic matter(OM), soot, fly ash, metal, and mineral. S-rich particles were dominant in all size bins, and 51%(by number) of S-rich particles were internally mixed with other particles. The fraction of organic coating particles was 13.7% in morning, 25.2% in afternoon, and 11% in evening, suggesting that the strong photochemical process during afternoon produced more secondary organic aerosols(SOA) on the surface of inorganic particles. Fly ash and metal particles were abundant during the day, suggesting the influence of emissions from coal-fired power plants and steel plants. The results indicate that the intense industrial emissions in the YRD significantly transported to the background areas. PM_(2.5) concentration may be lower in background air than in urban air but complex mixing state of aerosol particles indicates that the long-range transported particles substantially influenced the background air quality.  相似文献   
35.
With rapid economic growth and urbanization, the Yangtze River Delta(YRD) region in China has experienced serious air pollution challenges. In this study, we analyzed the air pollution characteristics and their relationship with emissions and meteorology in the YRD region during 2014–2016. In recent years, the concentrations of all air pollutants, except O_3,decreased. Spatially, the PM_(2.5), PM_(10), SO_2, and CO concentrations were higher in the northern YRD region, and NO_2 and O_3 were higher in the central YRD region. Based on the number of non-attainment days(i.e., days with air quality index greater than 100), PM_(2.5) was the largest contributor to air pollution in the YRD region, followed by O_3, PM_(10), and NO_2.However, particulate matter pollution has declined gradually, while O_3 pollution worsened.Meteorological conditions mainly influenced day-to-day variations in pollutant concentrations. PM_(2.5) concentration was inversely related to wind speed, while O_3 concentration was positively correlated with temperature and negatively correlated with relative humidity.The air quality improvement in recent years was mainly attributed to emission reductions.During 2014–2016, PM_(2.5), PM_(10), SO_2, NO_x, CO, NH_3, and volatile organic compound(VOC)emissions in the YRD region were reduced by 26.3%, 29.2%, 32.4%, 8.1%, 15.9%, 4.5%, and0.3%, respectively. Regional transport also contributed to the air pollution. During regional haze periods, pollutants from North China and East China aggravated the pollution in the YRD region. Our findings suggest that emission reduction and regional joint prevention and control helped to improve the air quality in the YRD region.  相似文献   
36.
基础设施与区域经济发展环境   总被引:23,自引:0,他引:23  
基础设施及其所形成的环境是人类自己营造的基础物质环境之一。是区域经济发展环境的主要组成部分。本文从四方面系统阐述了基础设施与区域经济发展之间的关系。提出了基础设施的引导与从属功能、带状经济的激发器和助推嚣等观点。分析了基础设施在改瞢生产环境与效率、空间经济集聚与扩散中的作用。以及基础设施短缺对区域经济发展的影响等。同时时归纳总结了我国土范国内已经形成的基础设施走廊的基本概况。  相似文献   
37.
Kim KH  Kim MY  Kim J 《Chemosphere》2005,59(11):1613-1624
The exchange processes of CH4 were investigated in a paddy field in the Hari area of Kang Hwa Island over an 8 day period in late April 2002. The quantification of CH4 fluxes was made under dry field condition of early spring by concurrently measuring its concentrations (at the two heights of 1 and 5 m) and the relevant micrometeorological parameters. To help elucidate the factors determining the mobilization characteristics of CH4, the results of our measurement data were examined using a number of approaches. The results of the trajectory analysis indicated that its concentration changed very sensitively with the influence of different source types, as seen from the air mass movement patterns. The concentrations and fluxes of methane, when examined over this short-term scale, showed moderately strong patterns across 24 h period in which higher values tend to occur during morning or evening. The overall results of our field measurements suggest that CH4 exchange processes in the paddy area proceeded in a fairly complicated manner. The study area behaved as a net source of CH4 to the atmosphere with a net daily emission rate of 3.6 mg m−2 despite the fact that downward deposition was observed more frequently than upward emission.  相似文献   
38.
Public evacuation preparation exerts an important impact on overall evacuation efficiency during regional evacuations. Early warnings often delay the occurrence of chemical accidents. Studying the characteristics of public evacuation preparation in such accidents will help develop better evacuation strategies considering the actual public response. In this work, the characteristics and factors influencing public evacuation preparation behaviors were analyzed by examining an evacuation case in China. The results indicated that the probability distribution of public's evacuation preparation time during a regional evacuation conforms to a Weibull distribution regardless of whether or not evacuation warnings were received. An estimation model of the traffic flow loading rate in a regional evacuation was then proposed on the basis of this finding. The results of this research can provide a reliable reference for evacuation modeling or logistics optimization for future incidents.  相似文献   
39.
Nowadays, the fine particle pollution is still severe in some megacities of China, especially in the Sichuan Basin, southwestern China. In order to understand the causes, sources, and impacts of fine particles, we collected PM2.5 samples and analyzed their chemical composition in typical months from July 2018 to May 2019 at an urban and a suburban (background) site of Chengdu, a megacity in this region. The daily average concentrations of PM2.5 ranged from 5.6-102.3 µg/m3 and 4.3-110.4 µg/m3 at each site. Secondary inorganics and organic matters were the major components in PM2.5 at both sites. The proportion of nitrate in PM2.5 has exceeded sulfate and become the primary inorganic component. SO2 was easier to transform into sulfate in urban areas because of Mn-catalytic heterogeneous reactions. In contrast, NO2 was easily converted in suburbs with high aerosol water content. Furthermore, organic carbon in urban was much greater than that in rural, other than elemental carbon. Element Cr and As were the key cancer risk drivers. The main sources of PM2.5 in urban and suburban areas were all secondary aerosols (42.9%, 32.1%), combustion (16.0%, 25.2%) and vehicle emission (15.2%, 19.2%). From clean period to pollution period, the contributions from combustion and secondary aerosols increased markedly. In addition to tightening vehicle controls, urban areas need to restrict emissions from steel smelters, and suburbs need to minimize coal and biomass combustion in autumn and winter.  相似文献   
40.
工业循环经济发展区域分异研究--以江苏省为例   总被引:3,自引:0,他引:3  
依据工业循环经济发展的基本原则,构建了包括产业及社会发展、资源减量、循环利用、污染减排、资源与环境安全五类指标在内的区域工业循环经济发展评价指标体系.运用AHP(层次分析法)方法,测算了指标权重,并以江苏省13个地级市为例进行了研究.用2003年的数据,对13个地级市的工业循环经济发展状况进行了评价.研究结果表明,江苏省13个地级市的工业循环经济发展水平可以分为四个层次,第一层次(水平良好)的城市为无锡、苏州、常州;第二层次(水平中上)的城市为盐城、南通、泰州;第三层次(水平中等)的城市为扬州、镇江、徐州、南京、连云港;第四层次(水平较差)的城市为淮安、宿迁.从总体上看,南部好于北部,东部好于西部,沿江沿海地区要好于内陆地区,靠近工业产业带的地区好于远离工业产业带的地区.  相似文献   
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