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121.
针对2012年珠江三角洲地区出现的2个典型灰霾个例(3月18~21日,10月13~15日),利用广州番禺大气成分综合观测基地的同期观测资料集,包括:能见度(VIS)、大气颗粒物质量浓度(PM10/PM2.5/PM1)、黑碳浓度(BC)等观测数据,分析过程中的气溶胶物理光学特征;配合过程的天气类型,气象要素和后向气流轨迹等对过程的成因进行综合分析.结果表明:在两个典型灰霾过程中,番禺日均能见度低至5.3km,黑碳浓度小时均值最高达19.0μg/m3、PM2.5浓度小时均值最高达163.0μg/m3,细粒子与黑碳粒子污染特征较为明显.两次典型灰霾过程分别受到冷锋前-均压场-冷锋前天气形势和台风外围-准均压场-冷锋前天气类型等不利于污染物输送扩散的气象条件影响.珠江三角洲地区低能见度的霾天气主要发生在高相对湿度的条件下,并可推断在珠江三角洲地区湿季的气溶胶吸湿能力明显高于干季.  相似文献   
122.
为研究沙尘天气大气可吸入颗粒物(PM10)与心血管系统疾病每日门诊人数的联系,采用半参数广义相加泊松回归模型(GAM),在排除了混杂因素如季节趋势、日历效应、气象因素和时间长期趋势等作用的前提下,分析2004年3月1日~5月31日沙尘暴频发区——甘肃省武威市大气PM10与多种心血管疾病每日门诊相对危险度(RR)的关系.结果表明,PM10与男、女总心血管系统疾病门诊RR均在滞后第2d(lag2)的联系有统计学意义.PM10分别在lag3和lag4对男、女性风湿性心脏病门诊RR的影响有统计学意义; PM10(lag2)与男性高血压门诊RR的联系有统计学意义.PM10在lag2对男性缺血性心血管疾病门诊RR的影响有统计学意义;PM10对男、女性心律失常以及充血性心力衰竭门诊RR的影响均无统计学意义.在调整了SO2和/或NO2后,PM10对男、女性心血管系统疾病门诊RR的作用有所下降,但在统计学上仍有意义.然而在分别调整了其他污染物后,SO2和NO2变得无统计学意义.沙尘天气PM10浓度分类模型分析表明,从正常清洁天、轻度污染天到扬沙天气、沙尘暴天气,随着PM10浓度水平的增大,心血管系统疾病(缺血性心血管疾病、充血性心力衰竭、心律失常、高血压、风湿性心脏病)门诊RR也随之增高,呈现一定的剂量效应关系.沙尘天气可吸入颗粒物可引起暴露居民多种心血管系统疾病(缺血性心血管疾病、充血性心力衰竭、心律失常、高血压、风湿性心脏病)门诊人数增多,且均呈现滞后效应. PM10浓度与心血管系统疾病门诊RR表现为一定的剂量效应关系.PM10浓度与沙尘天气强度有密切关系, 随着PM10浓度与沙尘天气强度的增大,暴露居民心血管系统多种疾病日门诊RR也增大,具体为:正常清洁天<轻度污染天<扬沙天<沙尘暴天.  相似文献   
123.
谷怿宸  曹乐 《环境化学》2022,41(1):144-159
自1997年在死海地区的大气边界层中观测到午间臭氧浓度迅速下降的现象后,研究学者们即对该地区的臭氧耗损现象(ozone depletion events,简称ODEs)展开了研究.而在此之前,大气边界层内的ODEs现象普遍被认为只会发生在极地地区的特殊大气现象.本文综述了关于死海地区ODEs研究的发展历史,主要展示了促...  相似文献   
124.
有别于单纯的"区域竞争"模式,国土空间开发格局逐渐成为新形势下我国区域发展的基础和前提,区域开发应满足前者的基本要求。本文根据各省基于县级单元的主体功能区划,以2010年为基年,通过建立人口、经济、产业结构和温室气体排放等多层次指标体系,评价"十二五"时期我国区域低碳经济与国土空间开发格局协调发展的进展程度。研究发现,城市化地区(重点开发区和优化开发区)以占不到18%的国土面积,集聚了1/2以上的人口和3/4的经济产出;农产品主产区的面积占比超过1/4,人口比例接近1/3;重点生态功能区面积比例接近56%,人口比例低于10%。2010—2014年,从全国范围看,各类主体功能区的发展态势与其功能定位基本吻合,表现为优化开发区、农产品主产区和重点生态功能区的人口和经济集聚度均有微降,而重点开发区有所上升;各区产业结构均有所优化,但农产品主产区和重点生态功能区产业结构调整的幅度小于城市化地区。具体到各省,研究发现本文所研究的"协调性"进展与传统意义上的东、中、西区域划分和发展水平并无直接关系,例如同为东部地区的京津冀三地,协调性进展有显著差异,也显示出三地协同发展的难度。相反,一些惯常认为发展较为落后的省区,例如河北、青海、山西等地,在经济发展与国土空间开发格局的协调性方面所付出的努力和成效走在前列。部分地区低碳发展与其国土空间开发格局呈现出相对不协调的态势,主要表现为农产品主产区和重点生态保护区都出现了经济集聚度上升、产业结构劣化、CO_2排放大幅度上升、排放强度甚至也上升的趋势。  相似文献   
125.
Extreme weather events such as floods and droughts can have devastating consequences for individual well being and economic development, in particular in poor societies with limited availability of coping mechanisms. Combining a dynamic computable general equilibrium model of the Yemeni economy with a household‐level calorie consumption simulation model, this paper assesses the economy‐wide, agricultural and food security effects of the 2008 tropical storm and flash flood that hit the Hadramout and Al‐Mahrah governorates. The estimation results suggest that agricultural value added, farm household incomes and rural food security deteriorated long term in the flood‐affected areas. Due to economic spillover effects, significant income losses and increases in food insecurity also occurred in areas that were unaffected by flooding. This finding suggests that while most relief efforts are typically concentrated in directly affected areas, future efforts should also consider surrounding areas and indirectly affected people.  相似文献   
126.
A historical survey was performed on 330 accidents involving domino effect, occurred in process/storage plants and in the transportation of hazardous materials; only accidents occurred after 1st-January-1961 have been considered. The main features – geographical location, type of accident, materials involved, origin and causes, consequences, domino sequences – were analyzed, with special consideration to the situation in the developing countries and compared to those from other previous surveys. Among the involved substances, LPG was the most frequent one, followed by liquid hydrocarbons. Process plants (38.5% of cases) and storage areas (33%) were the most common settings; 10.6% of past domino accidents occurred in transfer operations. The ratio between “two-step” and “three-step” domino accidents was found to be 6. A specific analysis of the accidents (84) occurred in the 21st century was performed, comparing them with the total set of accidents. Finally, a set of specific recommendations inferred from the results is provided.  相似文献   
127.
Methylation of mercury (Hg) to highly toxic methyl Hg (MeHg), a process known to occur when organic matter (OM) decomposition leads to anoxia, is considered a worldwide threat to aquatic ecosystems and human health. We measured temporal and spatial variations in sediment MeHg, total Hg (THg), and major elements in a freshwater lagoon in Sweden polluted with Hg-laden cellulose fibers. Fiber decomposition, confined to a narrow surface layer, resulted in loss of carbon (C), uptake of nitrogen (N), phosphorus (P), and sulfur (S), and increased MeHg levels. Notably, fiber decomposition and subsequent erosion of fiber residues will cause buried contaminants to gradually come closer to the sediment–water interface. At an adjacent site where decomposed fiber accumulated, there was a gain in C and a loss of S when MeHg increased. As evidenced by correlation patterns and vertical chemical profiles, reduced S may have fueled C-fixation and Hg methylation at this site.  相似文献   
128.
The paper focuses on risk sources under no legislative pressure in the field of prevention of major accidents. Despite this, they can represent significant sources of risk of accidents.The aim of the paper is to present the results of the risk assessment associated with the operation of enterprises not regulated by the SEVESO III Directive (the so-called subliminal enterprises), to provide information on possible operational problems and to verify the applicability of recognized risk analysis methods for these specific sources of risk. Last but not least, its purpose is to point out that subliminal enterprises, due to their location close to residential areas or areas with a high concentration of population, pose a serious risk to the population.The paper summarizes the results of the quantitative risk assessment of a specific enterprise not included in the Seveso Directive – a filling station. Filling stations are frequently located in built-up areas with a dense coefficient of habitability. Due to their number, location (e.g. close to residential areas), frequency of occurrence of persons in the area and handling of dangerous substances during normal operation, they can have negative or even tragic consequences to the life and health of the population.Due to the non-existent risk assessment methodology for enterprises with subliminal quantities of dangerous substances and the lack of a systematic search for risk sources, a risk assessment procedure for these companies is designed.  相似文献   
129.
共享发展理念要求全民共享改革发展成果,但当某些利于社会整体发展的项目设施建设将可能损害周边小部分群众个人利益时,政府管理部门如何合理协调处理好整体利益与个人利益的关系显得尤为重要,如果能提前做好相关调查应急预防工作,环境群体性事件的发生是完全可以避免的。本文从邻避冲突视角从微观上分析了环境群体性事件的发生过程、特点和内在机理,论述了邻避冲突引发的环境群体性事件的处理机制和政策措施。结果表明,舆情酝酿是引发环境群体性事件的关键,而解决舆情酝酿的关键则是参与人群边界的确定和恰当的信息公开。因此,建立有效的环境信息公开机制,对解决邻避冲突式的环境群体性事件具有重要的战略意义。同时,围绕邻避类项目的事前评价,提前做好损失预补方案和舆论疏导工作,有助于降低环境群体性事件发生的概率。具体说来主要可以通过建立环境类信息公开机制来了解民众的诉求,确保沟通渠道畅通;在信息公开的基础上,积极拓展并完善舆情监测与舆论引导机制,避免舆论因缺乏引导而持续发酵,引导舆论走向正面;建立环境类项目损害评估机制,本着公平、公正、公开、平等、自愿的原则进行不偏不倚的客观评估,制定科学合理的补偿方案;建立包括直接经济补偿和社会公益补偿等形式多样的环境类损失补偿机制;最后还要建立环境类事件过程监控机制,实行全过程、全方位管控,确保政府管理部门始终处于事件主导地位。在信息化不断发展、公民民主意识不断提升的背景下,努力提升政府治理能力显得尤为重要。在面对可能发生的矛盾焦点突出的环境群体性事件时,政府应当科学分析其产生发展的原因脉络,针对性地提出有效的解决方案。  相似文献   
130.
Based on an analysis of major recent social events in China, such as the 2008 Beijing Olympic Games, 2010 Shanghai World Expo, 2014 Nanjing Youth Olympic Games, and 2014 Beijing Asia Pacific Economic Cooperation Conference, mandatory, temporary, and indemnificatory quantitative policies aimed at protecting air quality, which were carried out by both central and local governments, made substantial contributions to changes and improvements in air quality. To some extent, the findings show that command and control measures play a significant role in protecting air quality, while the law and economic and voluntary environmental safeguard measures do not during major social events. Therefore, it reminds us the air quality could and will improve not only during major social events but also in the regular days if we implement appropriate environmental policies and safeguard measures.  相似文献   
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