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801.
Implementation of more stringent 8-hour ozone standards has led the U.S. Environmental Protection Agency to designate nonattainment status to 474 counties nationwide, many of which had never previously violated air quality standards. As states select emission control measures to achieve attainment in these regions, their choices pose significant implications to local economies and the health of their citizens. Considering a case study of one such nonattainment region, Macon, Georgia, we develop a menu of potential controls that could be implemented locally or in neighboring parts of the state. The control menu offers the potential to control about 20–35% of ozone precursor emissions in most Georgia regions, but marginal costs increase rapidly beyond 15–20%. We link high-order ozone sensitivities with the control menu to identify cost-optimized strategies for achieving attainment and for alternative goals such as reducing spatially averaged or population-weighted ozone concentrations. Strategies targeted toward attainment of Macon ozone would prioritize local reductions of nitrogen oxides, whereas controls in the more densely populated Atlanta region are shown to be more effective for reducing statewide potential population exposure to ozone. A U.S. EPA-sanctioned approach for demonstrating ozone attainment with photochemical models is shown to be highly dependent on the choice of a baseline period and may not foster optimal strategies for assuring attainment and protecting human health.  相似文献   
802.
通过对辽宁省移动通信基站的调查 ,对全省移动通讯基站的监测和分析从环保角度指出了基站建设中存在的主要矛盾 ,明确其对周围环境可能造成的影响 ,提出了今后基站建设中应注意的问题  相似文献   
803.
利用ADMS-城市模型模拟分析鞍山市大气环境质量   总被引:2,自引:0,他引:2  
方力 《环境保护科学》2004,30(6):8-10,13
利用鞍山市 2 0 0 2年的TSP(总悬浮颗粒物 )和SO2 (二氧化硫 )大气环境监测资料、污染源排放清单资料和气象资料 ,以及ADMS -城市大气扩散模型进行了鞍山市大气环境质量分析。结果表明 :鞍山市低架源对地面浓度的贡献较大 ,高架源对地面浓度的贡献相对较小。  相似文献   
804.
国家标准GB/T13201-91推荐基于单箱模型推导出来的A值法制定地方大气污染物排放总量标准,该文在放弃了控制区呈圆形的假设之后推导出可利用风向大气稳定度联合频率的更为详细的单箱模型,并用于计算杭州、宁波、温州、衢州的SO2排放年总控制量,在温州和衢州得到不同于A值法的结果。   相似文献   
805.
区域环境风险评价与管理初探   总被引:5,自引:0,他引:5       下载免费PDF全文
阐述了开展区域环境风险评价与管理的重要性,探讨了开展区域环境风险评价与管理的几个主要问题:区域环境风险水平的表征方法;区域环境风险的识别方法;区域环境风险评价的模式方法;以及区域环境风险管理的基本原则。开展区域环境风险评价与管理的目的是降低区域环境风险水平,减少人为事故带来的环境灾害与经济损失。给区域环境生态和公众健康一个较安全的保证。  相似文献   
806.
城市大气环境质量评价模糊识别理论模型   总被引:16,自引:0,他引:16       下载免费PDF全文
本文提出一种新的大气环境质量评价理论模型——模糊识别模型。提出了大气质量评价的指标综合权重矩阵概念及其确定方法。   相似文献   
807.
为了加快大气降尘样品的蒸发速度和报出数据的及时,经过分析总结,得出蒸发样品的步骤为:先电热套蒸发再水浴蒸发最后用电热板蒸发,这样既可以节省时间,又可以节约能耗,避免样品在空气中放置时间过长,空气中的尘粒进入样品中,影响样品测定的结果。  相似文献   
808.
Florida’s coasts have been transformed over the past three decades as population growth and unprecedented demand for individual shore access to bays and estuaries led to the creation of residential canal developments. Thousands of miles of channels and basins were dredged as a by-product of this urbanization process. The navigable waterways that resulted are now being stressed by increasing boat traffic and canal-side activities. Recognizing their common goal to preserve the recreational and ecological value of southwest Florida waterways, the Florida Department of Environmental Protection, the four-county West Coast Inland Navigation District, and the University of Florida Sea Grant College Program signed a Memorandum of Agreement. The signatories agreed to develop a science-based Regional Waterway Management System (RWMS), which is a new approach to waterway planning and permitting based on carefully mapped channel depths, a census of actual boat populations, and the spatial extent of natural resources. The RWMS provides a comprehensive, regional overview of channel conditions and the geographic distribution and severity of existing impediments to safe navigation and resource protection. RWMS information and analyses result in regional-scale permitting to accommodate water-dependent uses while minimizing environmental impacts and reducing public expenditures. Compared with traditional approaches to waterway management, the science-based RWMS is relatively unbiased, objective, transparent, ecologically sound, and fiscally prudent.  相似文献   
809.
Based on available literature data of [NO2 ], steady-state [·OH], and ·OH generation rate upon nitrate photolysis in environmental aqueous samples under sunlight, the steady-state [·NO2], could be calculated. Interestingly, one to two orders of magnitude more ·NO2 would be formed in photochemical processes in atmospheric water droplets compared to transfer from the gas phase. The relative importance of nitrite oxidation compared to nitrate photolysis as an ·NO2 source would be higher in atmospheric than in surface waters. The calculated levels of ·NO2 could lead to substantial transformation of phenol into nitrophenols in both atmospheric and surface waters.  相似文献   
810.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October-December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   
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