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271.
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
272.
Fluorescence excitation-emission matrix spectroscopy (EEMs) combined with fluorescence regional integration (FRI) analysis was used to investigate the composition and transformation of humic acid (HA) and fulvic acid (FA) from landfill. The EEMs of HAs at different landfill ages were characterized by two typical fluorescence chromophores with Ex/Em pairs at Ex = 420-470 nm/Em = 490-530 nm and Ex = 345-375 nm/Em = 450-465 nm. EEMs of FA were featured by other two distinctly different fluorophores with Ex/Em pairs at Ex = 315-335 nm/Em = 420-440 nm and Ex = 255-275 nm/Em = 425-455 nm. The results show that HA extracted from the refuse disposed in the year of 1989 was formed by connecting small-condensed aromatic structures with protein-like chains. Compared with HA extracted from the refuse disposed in the year of 1992, HA extracted from the refuse of 1996 had a higher fluorescence intensity and lower r(B,A) (the ratio of the fluorescence intensities of peak B and peak A) value. It contained low molar mass components, low aromatic condensation degree, and more easily oxidized substituents. This indicates that the landfill time strongly affects the EEMs characteristics of HA, and that the humification degree of HA increases with the landfill time. A red shift to a longer wavelength region and an increase of fluorescence intensity were observed when the concentration of HA was increased, suggesting that concentration had a great influence on the fluorescence characteristics of HAs. pH (2-12) also had significant effects on the fluorescence intensity, although it exerted no effect on the peak position of fluorescence of HA and FA. The results of FRI show that increasing concentration lead to more interactions among various structure components and that small molecular weight units tend to aggregate or be masked into more complicated and larger structures. The pH influence on the fluorescence intensity of HA seems mainly through molecular configuration, while the fluorescence intensity change with pH may be due to various substituents of FA. 相似文献
273.
Guiling?L.?ZhangEmail author Jing?Zhang Jie?Xu Jingling?L.?Ren Sumei?M.?Liu 《Water, Air, & Soil Pollution: Focus》2007,7(6):645-654
CH4 concentrations in both the surface and bottom waters of Jiaozhou Bay were determined during four surveys in 2003, which showed
variability with both seasons and tidal cycles. Atmospheric fluxes of CH4 in Jiaozhou Bay showed obvious seasonal and spatial variations, with the highest values occurring in summer and the lowest
in winter. The annual emission of CH4 from Jiaozhou Bay was estimated to be . CH4 in the water column of Jiaozhou Bay was found to come from several land-sources including riverine water input, sewage water
input and groundwater input. The spatial and temporal variation in distributions and atmospheric fluxes of CH4 in Jiaozhou Bay was influenced mainly by the input of polluted river waters and the sewage effluents along the eastern coast,
which highlights the effects of human impacts on CH4 emission rates. 相似文献
274.
利用1985年至1987年三年大气监测数据,对唐山市大气自动监测子站整体代表性作了系统分析,结果表明,子站布局合理,各子站监测的SO2、TSP年均值,季均值相对误差,百分位数相对误差符合《国家环境监测网络大气监测点位验收标准》规定的指标,具有整体代表性。 相似文献
275.
Yueqi Jiang Jia Xing Shuxiao Wang Xing Chang Shuchang Liu Aijun Shi Baoxian Liu Shovan Kumar Sahu 《Frontiers of Environmental Science & Engineering》2021,15(5):88
276.
PM(10) concentration and chemical composition (ions and carbon compounds) at three sampling stations in Rome and in its surroundings was determined daily during a one-month field study, carried out during December 2003. PM concentration at the traffic station was considerably higher than at the urban background and semi-rural stations; elemental carbon was detected as one of the chemical components responsible for this increase. The difference in the concentration of sulphate and ammonium was negligible, as it was expected for secondary pollutants. A negative artefact in the determination of ammonium nitrate by means of heated automatic monitors was highlighted. The dilution properties of the lower atmosphere were traced by means of a natural radioactivity monitor. This parameter has been found to play an essential role in pollution buildup. A considerable increase in PM concentration was observed to coincide with periods of atmospheric stability. The main difference in PM composition between periods of high concentration and periods of "clean" air was found to be in the increase of ammonium nitrate concentration. 相似文献
277.
Masako Konishi 《Environmental Communication: A Journal of Nature and Culture》2018,12(4):558-573
This article assesses the success of WWF Japan’s “Background Media Strategy” in influencing Japanese mainstream news outlets’ coverage of climate change negotiations. WWF Japan adopted this “Background Media Strategy” after the Bali COP in 2007; instead of lobbying, it aims to build journalists’ expertise. This article examines its success after seven years through three research approaches: the analysis of participant lists; two surveys (conducted in 2009 and 2015); and a content analysis of climate change articles that appeared in four large mainstream newspapers between April and July 2015. Based on these different data, the author concludes that the new media strategy was successful: Japanese journalists increasingly rely on information provided by WWF Japan and less on information provided by the government and industry. This experiment suggests that a new relationship between global NGOs and the media can improve environmental communications—an approach that could help advocacy groups around the world. 相似文献
278.
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
279.
四川省泥石流预报的区域临界雨量指标研究 总被引:29,自引:0,他引:29
本文在讨论四川泥石流分区的基础上,论述了区域泥石流临界雨量指标的确定方法及应用问题。并制定了四川泥石流预报的区域临界日雨量和临界小时雨强指标。 相似文献
280.
近五年中国自然灾害空间分布格局及其月动态变化研究 总被引:5,自引:7,他引:5
作者根据《中国减灾》所载1990~1994年月灾情记录,经统一编码和标准化处理,建立了以行政县为基本单元的数据库。进而对近五年来中国自然灾害空间分布及其月动态变化进行分析,并与1949~1990年中国自然灾害的平均状况进行对比。 相似文献