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371.
The operational designing of Environmentally Sustainable Economic Development (ESED) emerges as an urgent and demanding task. Even though ESED has paved the way for thought-provoking and constructive scientific dialogue, appeal for designing an operational ESED is still lagging behind the needs of contemporary societies, leaving much to be desired. With this in mind, the present paper will aim at delineating principles for the operational application of ESED. First, the preservation of crucial properties of environmental functions and ecosystems, emerges as a prime condition of ESED. The second condition concerns the provision of the economic process with sufficient natural inputs; in this context, the paper intends to trace certain operational tenets governing the use of natural resources. Finally, the appropriate institutional settings for the operational design of ESED are traced. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   
372.
Reference conditions are a key concept in the European Water Framework Directive (WFD). The WFD stipulates that the ecological status of a given water body shall be assessed by quantifying the deviation from a set of reference conditions that represent the stable state of an ecosystem in the absence of significant human disturbance. This concept is subject to criticism from several authors, particularly because underlying ecological concepts are weak and the distinction between natural variability and the effects of anthropogenic activities on ecosystem function will become increasingly artificial. In this paper, a sociologist and an aquatic ecologist examine the origin, successes and limits of the reference conditions concept and raise important questions about applying this concept in practice. We argue that this concept fitted specific needs from different institutions and stakeholders which promoted the WFD. Monitoring practices using this concept require some adaptations. Setting goals for restoration based on reference conditions is more problematic. A more adaptive management approach would be wiser.  相似文献   
373.
为明确我国灭火专业标准体系发展的方向和重点,分别从灭火剂、灭火器、灭火救援装备、消防通信和灭火救援管理5个方面对我国和国际消防标准化组织、美国消防标准研究机构及协会发布的灭火救援标准共200项进行了比较研究。结果表明,我国固体和液体灭火剂标准处于国际领先水平,但气体灭火剂标准未涉及部分新型卤代烷气体灭火剂;灭火器标准修订情况落后于国际标准;灭火装备类标准数量较多,但不够全面且缺乏系统性;消防通信系统标准落后于目前通信技术的发展;灭火救援管理类标准是我国消防标准化最为薄弱的方面。针对上述问题,对我国灭火专业标准体系的发展和完善提出了改进意见。  相似文献   
374.
Guangzhou is a city in southern China that has experienced very rapid economic development in recent years. The city's air has very high concentrations of various pollutants, including sulphur dioxide (SO2), oxides of nitrogen (NOx), ozone (O3) and particulate. This paper reviews the changes in air quality in the city over the past 15 years, and notes that a serious vehicular-related emissions problem has been superimposed on the traditional coal-burning problem evident in most Chinese cities. As NOx concentrations have increased, oxidants and photochemical smog now interact with the traditional SO2 and particulate pollutants, leading to increased health risks and other environmental concerns.
Any responsible NOx control strategy for the city must include vehicle emission control measures. This paper reviews control strategies designed to abate vehicle emissions to fulfill the city's air quality improvement target in 2010. A cost-effectiveness analysis suggests that, while NOx emission control is expensive, vehicular emission standards could achieve a relatively sizable emissions reduction at reasonable cost. To achieve the 2010 air quality target of NOx, advanced implementation of EURO3 standards is recommended, substituting for the EURO2 currently envisioned in the national regulations. Related technical options, including fuel quality improvements and inspection/maintenance (I/M) upgrades (ASM or IM240), are assessed as well.  相似文献   
375.
High-pressure membrane process is one of the cost-effective technologies for the treatment of groundwater containing excessive dissolved solids. This paper reports a pilot study in treating a typical groundwater in Huaibei Plain containing excessive sodium, sulfate and fluoride ions. Three membrane systems were set up and two brands of reverse osmosis (RO), four low-pressure RO (LPRO) and one tight nanofiltration (NF) membranes were tested under this pilot study. An apparent recovery rate at about 75% was adopted. Cartridge filtration, in combination with dosing antiscalent, was not sufficient to reduce the fouling potential of the raw water. All RO and LPRO systems (except for the two severely affected by membrane fouling) demonstrated similar rejection ratios of the conductivity (~98.5%), sodium (~98.5%) and fluoride (~99%). Membrane fouling substantially reduced the rejection performance of the fouled membranes. The tight NF membrane also had a good rejection on conductivity (95%), sodium (94%) and fluoride (95%). All membranes rejected sulfate ion almost completely (more than 99%). The electricity consumptions for the RO, LPRO and NF systems were 1.74, 1.10 and 0.72 kWh?m-3 treated water, respectively. The estimated treatment costs by using typical RO, LPRO and tight NF membrane systems were 1.21, 0.98 and 0.96 CNY?m-3 finished water, respectively. A treatment process consisting of either LPRO or tight NF facilities following multi-media filtration was suggested.  相似文献   
376.
针对我国建设用地土壤污染风险管控标准存在的保护目标单一、毒理学基础数据库有待完善、缺少因地制宜的地方标准及统一的标准制定规程等问题,本文研究了加拿大联邦及其省级土壤质量指导值分级制定技术规程,梳理了加拿大污染场地修复目标值的确定方法。在此基础上,从保护人体健康与保护生态环境并重、提升建设用地土壤污染风险管控标准的基础研究水平、研究基于地方实际的建设用地土壤污染风险管控标准和出台统一的标准制定规程文件等四个方面提出对策建议,以期为我国建设用地土壤污染风险管控标准制修订提供参考。  相似文献   
377.
《大气污染防治法》授权国家环境保护主管部门制定大气污染物排放标准,但关于标准的法律规则还不够全面,在一定程度上影响了排放标准的功能发挥,也给标准限值确定带来了困难。当前国家正在对《大气污染防治法》进行修订,为完善相关标准条款,本文在对我国大气污染物排放标准立法现状分析的基础上,借鉴国外相关标准的立法规则和我国标准实践经验,提出了适用于我国的大气污染物排放标准制定的主要法律原则和程序建议。研究认为,制定大气污染物排放标准应考虑污染物对公众健康、空气质量和生态环境的影响,以及可采取的污染控制技术措施等情况,通过技术经济论证确定排放限值和相关技术要求,做到技术可行、经济合理、减排效益突出。标准制定过程要充分听取各方意见,经标准评审委员会审查通过后方可按照部门规章批准发布。  相似文献   
378.
Monsoon flooding occurred in the main areas of the Khyber Pakhtunkhwa, Punjab, and Balochistan as well as parts of Gilgit Baltistan of Pakistan and Azad Jammu Kashmir in July 2010. Water-borne diseases such as cholera, enteric fever, and dysentery were common among the inhabitants of flood-affected areas which were selected for sample collection. In the present study, 10 sites in District Peshawar were selected and drinking water samples collected. These samples were analyzed for the total plate count (TPC), total coliform bacteria (TCB), total fecal coliform bacteria (TFCB), Escherichia coli (EC), Pseudomonas aeruginosa (PA), Vibrio cholerae (VB), Salmonella Shigella, and Staphylococcus aureus. The TPC ranged from 8 × 101 to 7 × 104 CFU/ml. The TCB ranged from <1.1 to 280 MPN/100 ml. Twenty percent of the samples were contaminated with TFCB, EC, Salmonella, Shigella, and Staphylococcus aureus, while only one sample contaminated with PA. Forty percent of the samples were contaminated with VB. The surface and well water was greatly contaminated by flooding and major improvements on priority basis are essential.  相似文献   
379.
ABSTRACT

Low-carbon development is an essential measure to combat climate change, and the establishment of low-carbon standards is an important means to achieve low-carbon development. Due to the differences in size and development level among counties of China, the applicability and fairness of county-level low-carbon standards are very important in this country. This study analyzed the trends of county-level carbon emissions in China, defined the peak value of carbon emissions per capita, summarized the characteristics of existing low-carbon standards, and proposed a fair county-level low-carbon standard based on carbon emissions per capita. The results of our analysis suggest that, under the constraints of carbon emissions reduction policies, China’s carbon emissions per capita will tend towards a stable range. Additionally, by referring to predictions results of the peak value of China’s carbon emissions per capita, it was determined that, in low-carbon development targets, China’s county-level carbon emissions per capita should be set within the range of 2–4 tons. Besides setting low-carbon standards, the Chinese government and private enterprises should develop low-carbon technologies as soon as possible and innovate management models to achieve the win–win situation of simultaneous economic growth and carbon emissions reduction.  相似文献   
380.
《Environmental Hazards》2013,12(1):53-58
In 1984 the Mitigation Implementation Conference recognized the need for effective management of urban development in terms of building standards and land-use zonation. In the intervening 25 years, significant progress has been made in the development of building codes and hazard mapping for disaster risk reduction; however, the failure to promulgate, implement and enforce regulation of development has resulted in the dramatic expansion of exposure and risk. It is now necessary to re-assess regulatory policy and practice. New approaches to regulatory compliance must be explored, including participatory regulation and reliance on cultural and religious bases for individual commitment to community safety.  相似文献   
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