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221.
我国城市生态承载力研究进展   总被引:1,自引:0,他引:1  
从生态承载力角度研究区域资源-生态-环境问题,是当今生态学、地理学和经济学等学科研究的热点与前沿领域之一。依据现有研究成果,阐述了承载力的概念和什么是城市生态承载力,并对生态承载力的研究方法、研究趋势及其研究存在的问题和方法途径及提高城市生态承载力的对策建议进行了简述。  相似文献   
222.
The sulphur dioxide and nitrogen oxides emissions from all sources in Alberta, Canada, during 1982 amounted to 488,297 and 353,511 tonnes, respectively. During this year deposition of wet sulphate from all stations in the province, 8 kg ha–1 yr–1, compares well with the five-year average (1978–1982) value of 10 kg ha–1 yr–1. These measurements are about one-half of the wet sulphate deposition criteria of 20 kg ha–1 yr–1 established for protecting the moderately sensitive aquatic ecosystem in eastern Canada. Due to dry, cold, continental climate conditions of Alberta, dry sulphate or sulphur deposition is equally or more important than wet deposition. No effects of the long-range transport of atmospheric pollutants (LRTAP) on the ecosystems in Alberta have been observed to date. Atmospheric deposition target loadings of SO4 –2, NO3 , and H+ for Alberta and western Canadian environmental conditions should be developed to protect the highly sensitive ecosystems. Some future research and monitoring priorities for Alberta and western Canada are outlined.  相似文献   
223.
区域农业生态环境质量综合评价方法与模型研究   总被引:24,自引:0,他引:24  
为了客观准确的评价区域农业生态环境质量,引入灰色系统理论中的关联度分析法,提出了区域生态环境质量的多级模糊综合评价——灰色关联优势分析复合模型,并以安徽省芜湖市区域农业生态环境质量的综合评价为例,根据芜湖市区域农业生态环境调查与监测资料,进行了实例研究。结果表明:安徽省芜湖市区域农业生态环境已经受到了明显的污染,并且各区域污染水平具有一定的差异;芜湖市区域农业生态环境质量优劣的关联序依次为:南陵县、芜湖县、繁昌县和城市郊区。   相似文献   
224.
许晓路  申秀英 《灾害学》1994,9(1):79-83
大气环境污染和人体肺癌发生率密切相关。工业和交通排放大气污染物、厨房污染、吸烟、复印机和居室装饰等造成的大气环境污染过程均能造成居民肺癌发病率的上升。应通过控制工业污染、改变能源结构、戒烟及绿化造林等措施加以解决。  相似文献   
225.
The Pearl River Delta (PRD) is one of the most industrialized, urbanized and populated regions in China, and thus has been long suffering from severe air pollutions. Space data provide a unique perspective for investigating the atmospheric environment at a regional scale. By utilizing multiple satellite retrievals from 2005 to 2013, this study presented, for the first time, the spatial patterns and temporal trends of typical air pollutants over PRD and its vicinity. As viewed from space, aerosol optical depth (AOD), NO2 and SO2 all had their higher values at the central part of PRD, and showed clear descending gradients as moving to the outskirt of this region. As to the inter-annual variation, all these pollutants had decreasing trends in PRD during the study period, which generally agreed with the relevant in situ measurements. However, the satellite retrievals differed from ground measurements when addressing NO2 and SO2 in the vicinity of PRD. This work also provides the inter-comparison among PRD and three other metropolitan clusters in China: PRD had relatively high AOD, moderate NO2 and low SO2 levels, and it was the only region achieving the effective reduction of NO2 and SO2 during last decade. Unlike the previous three pollutants, HCHO observed by satellite showed very special patterns: it had a relatively homogeneous spatial distribution over both of PRD and its vicinity, and presented an opposite increasing trend from 2005 to 2010. Moreover, PRD had the highest HCHO level among all the metropolitan clusters, hinting a considerable contribution of biogenic origins of HCHO in PRD.
  相似文献   
226.
The present work relates to galvanized structures with several years of time life subjected to atmospheric corrosion, like galvanized high tension steel pylons. The mass and fate of zinc released is evaluated both via empirical and experimental procedures. The corrosion rate determination requested atmospheric condition characterization, especially for SO 2 concentration and experimental activities focused on soil sampling around pylons. The soil zinc content, total and exchangeable, is determinates by different analytical procedures. The zinc diffusion in environment and the zinc extension under the top soil is evaluated using 1-dimensional mathematical model for miscible species in porous soil.  相似文献   
227.
执行《环境空气质量标准》应注意的问题   总被引:2,自引:0,他引:2  
随着《环境空气质量标准》GB30 95- 1 996(简称新标准 )取代 GB30 95- 82 (简称旧标准 ) ,大气环境质量现状监测和影响评价工作需要作出相应的修正以适应新标准的要求 ,从实际工作出发 ,总结出了执行新标准应注意的一些问题及其解决方法。  相似文献   
228.
近地层氮氧化物和臭氧的区域分布研究   总被引:1,自引:1,他引:1       下载免费PDF全文
介绍了近地层氮氧化物和臭氧的区域分布研究方法,使用简化的区域尺度大气污染物传输模型和光化学反应模型,模拟计算了1990年中国主要城市排放氮氧化物的情景下,夏季(7月)主要城市的氮氧化物和相应的臭氧在近地层的浓度分布。   相似文献   
229.
Peroxyacetyl nitrate observed in Beijing in August from 2005 to 2009   总被引:1,自引:0,他引:1  
Measurements of peroxyacetyl nitrate(PAN) were made at a Beijing urban site each August from2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3(2005) to 11.7 μg/m3(2007); however, it decreased rapidly in 2008(4.1 μg/m3).Generally, the variation over the 5 years showed a rise in the first part of the study period,followed by a decline. We considered two categories of local and regional air masses in this study, which revealed that the PAN concentration in Beijing was affected mainly by southeastern air masses. The August PAN variation was influenced predominantly by local air masses in 2005,but by 2009 regional air masses had become more important. This study showed the level and variation of PAN in the month of August in 5 consecutive years for the first time, and proved that control measures are useful in decreasing photochemical pollution; hence, these measures are probably feasible for other megacities too. Furthermore, this method of analyzing regional and local impacts might be useful for other studies as well.  相似文献   
230.
我国区域性大气污染问题频频发生,成为当前亟待解决的重大环境问题。区域联防联控工作需要建立相应的区域空气质量监测体系和评价方法,这对已有的监测体系提出了新的要求。在区域监测体系中需要增加臭氧、细粒子等区域性污染物及其前体物的监测,同时设立区域监控点使监测网络覆盖面由城市建成区拓展到广大近郊及农村地区。采用移动式柱浓度监测和卫星遥感监测等多样化监测手段结合超级空气站来增强区域综合监测和源解析能力。在区域内搭建监测信息共享平台和实时发布机制并建立区域空气质量预警预报系统。建立区域内统一的质量管理和质量控制方案,城市监测点质控工作由所在省市管理,区域监控点质控工作由国家统一直管。采用分区分层次的区域空气质量评价方法,评价因子包括所有六项监测指标。  相似文献   
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