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221.
Kazuo Kamura Yu Hara Bulent Inanc Masato Yamada Yuzo Inoue Yusaku Ono 《Journal of Material Cycles and Waste Management》2005,7(2):66-70
It is always possible for impermeable layers to exist in landfills. When they do, the properties of the solution at the exit of the leachate-collection system might not accurately reflect the overall properties of the landfill. This study examines whether resistivity monitoring is effective for determining the influence of impermeable layers on the leachate. The test cell used in this study was filled with waste made up mainly of incinerator ash and shredded incombustible material. Three lines of resistivity sensors were laid in the uppermost layer of the fill. A resistivity profile was recorded periodically from each of these lines. The water-table level and leachate properties were measured concurrently. Leachate conductivity was mainly controlled by concentrations of the main ions, and it correlated inversely to variations in resistivity. Temporal changes in the resistivity of the fills are an excellent means of assessing the leaching in fills. Monitoring the properties of leachate, combined with resistivity profiling, is extremely useful for interpreting the temporal changes of properties in landfills containing impermeable layers. 相似文献
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223.
针对仪化热电厂将循环水用作冲灰水,导致浓缩倍率只有1.6,以及凝汽器铜管腐蚀结垢严重等问题,提出了隔断循环水与冲灰水的直接联系,实现闲路循环,对凝汽器铜管进行酸洗,并对循环水实施加缓蚀阻垢荆、杀菌剂和旁流过滤等办法,全部实施后产生了很好的效益,值得借鉴。 相似文献
224.
胡苑 《中国环境管理干部学院学报》2003,13(4):14-17
本文通过分析清洁生产和消费的含义,指出清洁生产的调整范围包括消费环节.我国《清洁生产促进法》的内容体现了清洁生产从生产领域扩展到消费领域这一新动向.本文论证了这一新发展的正当性和合理性,最后结合具体法条进行分析,指出相关制度手段和意义所在. 相似文献
225.
The environmental situation in Ghana is characterized by desertification, land degradation, deforestation, soil erosion, and
inadequate water supply in the northern regions of the country. The population as a whole is growing at a rate of 3% per annum,
with even greater urban growth rates, due to rural out-migration. Large parts of the coastal zone in the south are rapidly
developing to become one large suburbanized area. Water quality is particularly threatened in the urban and industrialized
areas, which are mainly located in the southern part of the country. The coastal lagoons and coastal waters are moderately
to heavily polluted. Erosion extends along the whole Ghanaian coast with excesses, for example, in the Keta area, where during
the last century over 90% of the original buildings have been washed awayby the sea. The obvious environmental consequences
of the mining sector are illustrative of the environmental threats caused by a fast growing industry and industrializing agriculture,
in a country where environmental policy is only in its formative years. Desertification, food insecurity and coastal erosion
all contribute to an increasing number of environmental refugees.
Environmental policy in Ghana is a post-Rio phenomenon. Environmental laws, a Ministry of Environment, Science and Technology,
an advisory National Committee for the Implementation of Agenda 21, and a fully mandated environmental administration have
been established. This administration advocates a progressive attitude towards environmental legislation and points out the
specific utility of economic and legal instruments in environmental management in this relatively fast developing country.
The choice of instruments for environmental management is increasingly influenced by the specific state of African environmental
and technological capacity and by a call for the recognition of the role of traditional customs in nature conservation. This
African perspective on environmental management is further intensified by an unmet need for regional, transboundary cooperation
in the West African subcontinent. This specific West African context calls for an elaboration of an effective capacity-building
program for environmental management in the area. 相似文献
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本文调查研究了孔林内动植物物种资源的现状,报道了高等植物物种有356 种( 包括变种和亚种) ,隶属91 科243 属,鸟类有28 种,分属9 个目,并提出了保护孔林动植物物种资源的几点对策 相似文献
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229.
风险投资已经被各国公认为中小企业尤其是高科技企业成长的"推进器"。为了深入理解风险投资的本质,从风险投资的行为和基本特征入手,通过对价值理论的回顾和企业价值表述方式的描述,揭示了风险投资作为发现价值型投资的本质,即通过发现投资对象的潜在价值并通过不断的增值服务使潜在的价值逐步显化,从而得到大多数投资者认可后实施股权转让获得丰厚回报的投资本质。 相似文献
230.
Hydrological Connectivity Between Headwater Streams and Downstream Waters: How Science Can Inform Policy1 总被引:1,自引:0,他引:1
Tracie‐Lynn Nadeau Mark Cable Rains 《Journal of the American Water Resources Association》2007,43(1):118-133
Abstract: In January 2001, the U.S. Supreme Court ruled that the U.S. Army Corps of Engineers exceeded its statutory authority by asserting Clean Water Act (CWA) jurisdiction over non‐navigable, isolated, intrastate waters based solely on their use by migratory birds. The Supreme Court’s majority opinion addressed broader issues of CWA jurisdiction by implying that the CWA intended some “connection” to navigability and that isolated waters need a “significant nexus” to navigable waters to be jurisdictional. Subsequent to this decision (SWANCC), there have been many lawsuits challenging CWA jurisdiction, many of which are focused on headwater, intermittent, and ephemeral streams. To inform the legal and policy debate surrounding this issue, we present information on the geographic distribution of headwater streams and intermittent and ephemeral streams throughout the U.S., summarize major findings from the scientific literature in considering hydrological connectivity between headwater streams and downstream waters, and relate the scientific information presented to policy issues surrounding the scope of waters protected under the CWA. Headwater streams comprise approximately 53% (2,900,000 km) of the total stream length in the U.S., excluding Alaska, and intermittent and ephemeral streams comprise approximately 59% (3,200,000 km) of the total stream length and approximately 50% (1,460,000 km) of the headwater stream length in the U.S., excluding Alaska. Hillslopes, headwater streams, and downstream waters are best described as individual elements of integrated hydrological systems. Hydrological connectivity allows for the exchange of mass, momentum, energy, and organisms longitudinally, laterally, vertically, and temporally between headwater streams and downstream waters. Via hydrological connectivity, headwater, intermittent and ephemeral streams cumulatively contribute to the functional integrity of downstream waters; hydrologically and ecologically, they are a part of the tributary system. As this debate continues, scientific input from multiple fields will be important for policymaking at the federal, state, and local levels and to inform water resource management regardless of the level at which those decisions are being made. Strengthening the interface between science, policy, and public participation is critical if we are going to achieve effective water resource management. 相似文献