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931.
本文在介绍嫩江齐齐哈尔江段基本情况及污染源排放状况基础上,分折了嫩江齐齐哈尔江段水环境质量污染的主要问题,提出了嫩江齐齐哈尔江段可持续发展与相关对策。 相似文献
932.
Guanabara Bay is a 384-km2 coastal bay with 70% of the population of the metropolitan area of Rio de Janeiro located within its drainage basin. The
water quality of the Bay is impacted by domestic and industrial runoff, of which only 15% has been adequately treated. However,
based on a 14-year monitoring program, the water quality for most of Guanabara Bay remains acceptable because of intense tidal
flushing, and we failed to find a worsening of conditions during the 14-year study. The inner shallow regions of the Bay,
the western and northwestern parts, receive most of the drainage from metropolitan Rio de Janeiro. It is here that the water
quality is alarmingly poor, characterized by hypertrophic conditions and occasional hypoxic events. Fecal coliform counts
in these inner reaches of the Bay are 4–100 times higher than the maximum acceptable count for recreational waters. Hypertrophic
conditions prevail in Guanabara Bay, which is characterized by low dissolved oxygen, high biochemical oxygen demand, peaks
in fecal coliform, and extremely high chlorophyll-a concentrations, which reflect high quantities of nutrients entering the system. These anthropogenic pressures are a threat
to planktonic and benthic communities and are reminiscent of San Francisco Bay 30 years ago. The Guanabara Bay water quality
could be returned to pre-1950 conditions, but it would require sufficient political will and economic investment to ensure
that at least 80–90% of the domestic and industrial sewage were treated adequately.
Electronic Publication 相似文献
933.
America has always had to confront environmental problems, but it wasn't until after World War II that most Americans began to develop the kind of consciousness about environmental issues that has played such a role in domestic politics over the past quarter century. After the surge of post war growth, we began to recognize the limits of our ability to exploit our environment for private gain, thus creating environmental awareness and ultimately a political movement. In 1970, President Nixon created the Environmental Protection Agency, and appointed William Ruckelshaus as Director. Ruckelshaus was succeeded by Russell Train and Douglas Coste, and all three men began to make serious headway in the effort to clean up the nation's environment. In 1980, however, President Ronald Reagan, taking an anti-Federal government involvement in the private sector stance, began to seriously cut the budget of the EPA. He appointed Ann Gorsuch, who cut the budget as she believed the President wished, but her poor relationship with the Congress eventually forced her to resign. President Reagan requested that Bill Ruckelshaus return, and EPA has been blessed with good leadership ever since. During the Bush years, EPA director William Reilly even managed to pass sweeping acid rain control legislation. When Bill Clinton was elected President in 1992, he did not possess a strong environmental record, however his running mate, Al Gore, most certainly did. EPA administrator Carole Browner, in fact, was a former Gore staffer and the White House environmental office is led by former Gore people. Clinton and Gore have attempted to bring a degree of flexibility to environmental regulation, and have also involved themselves personally in resolving environmental disputes. For instance, they and Secretary of the Interior Bruce Babbit worked to fashion a long-term plan for the Florida Everglades that helped warring groups and interests come to consensus. With the 1994 Republican victory in the Congressional elections, it appeared that the environment may once again be in danger, as the Contract with America pledged to reduce or eliminate environmental controls. Popular opinion, however, caused the Congress to change their views and even directed them to pass environmental legislation that has won the support of both the business and environmental protection sectors. These developments have displayed that Americans care deeply about the environment and provide the basis for a genuine bipartisan consensus on environmental issues which will increasingly emphasize thoughtful and effective technological solutions in the future. Although the benefits of this legislation have been drastic, we are now dealing with problems requiring more subtle and sophisticated answers than we needed in the past. Because of this, political leaders will look to the classrooms and laboratories to produce the answers to the environmental problems of the future, and in turn will be willing to support educators and researchers with resources and political clout. Neither the politicians nor the business community can solve these problems without a close working relationship with the world of environmental and biotechnology. Building that collaborative relationship is one of the most important challenges we face as we approach the 21st century. It is also, particularly for those of us who have been laboring in the environmental vineyard for years, one of the most exciting. 相似文献
934.
935.
哈尔滨大气中PAHs污染特征 总被引:2,自引:0,他引:2
多环芳烃(PAHs)是大气中广泛存在的一种有毒污染物,因其具有"三致"毒性,已成为关注的焦点。本文通过在哈尔滨市区设置大气采样点,利用大流量主动采样器进行为期一年的大气样品采集,对大气中PAHs的浓度、污染特征进行了研究,并深入探讨了PAHs的污染源和贡献率,结果表明,哈尔滨大气中∑16PAHs浓度范围为6.3~340 ng/m3,平均浓度为100±94 ng/m3,主要以低分子量的PAHs为主。与国内外的研究相比,哈尔滨大气中PAHs的污染处于中等污染水平。PAHs具有明显的季节差异,低温气象条件和排放源的增强是导致冬季PAHs污染加重的主要原因。 相似文献
936.
937.
室内环境污染是继煤烟污染和光化学污染之后的全球第三大空气污染问题,它对居民健康和整个社会经济均会造成重大的损失。本文简述了室内空气污染的种类及其对人体健康的危害,从4个方面提出了防治室内空气污染的措施。 相似文献
938.
促进我国环保产业发展的实证研究——对《水污染防治行动计划》的解读 总被引:1,自引:0,他引:1
基于2010年《中国投入产出表》,结合环保产业统计调查,构建环保产业外部化投入产出表,采用投入产出局部闭模型定量研究水污染防治行动计划对环保产业的促进作用,并对拉动效应的时滞特性进行分析。研究发现:行动计划的实施将直接带动水污染防治专业设备制造、环境监测专用仪器设备、环境咨询服务等相关领域发展,对环保产品和环保服务的直接贡献为1.4万亿,间接贡献约5 000亿。拉动效应的时滞特性分析表明,行动计划投资对环保产业的刺激效应在2017年达到高峰,然后逐年递减。 相似文献
939.
940.
南太湖地区湖州市大气PM_(2.5)中多环芳烃的研究——污染现状和人体暴露健康风险评价 总被引:1,自引:0,他引:1
运用智能综合大气采样仪采集了南太湖地区湖州市大气PM 10和PM 2.5样品,采用高效液相色谱检测了该样品中16种多环芳烃化合物,通过苯并(a)芘(Ba P)致癌等效浓度、人群终身超额致癌风险和预期寿命损失等指标,评价湖州市大气PM2.5中多环芳烃的人群健康风险。结果表明:全市大气PM 2.5中多环芳烃全年总平均浓度为11.59 ng/m 3,季平均浓度范围在4.775~23.98 ng/m3之间,季节之间呈现一定的变化,冬季秋季春季夏季;全市大气PM 2.5中多环芳烃的苯并(a)芘总致癌等效浓度(TEQ)年均值为1.138 ng/m3,污染所致的成人和儿童的终身超额致癌风险分别为8.7×10-6和6.0×10-6,成人的预期寿命损失为44.5 min。 相似文献