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691.
The ability to achieve urban sustainability has become an indication of the competence of a municipal government aiming to gain world class status for the city. While both Guangzhou and Hong Kong are Chinese cities having their own formulation of urban sustainability, the implementation details and the actual sustainability blueprints are very different. As a result, the outcomes and prospects for urban sustainability are also different.

Hong Kong has adopted a less integrative and more institutionally-oriented approach for urban sustainability. Guangzhou has used the conventional approach to formulate an integrated sustainability programme for its local Agenda 21. Hong Kong's action plan emphasizes improving coordination, making objective assessments and achieving consistency in policy-making. Guangzhou, on the other hand, emphasizes the meeting of concrete environmental targets. Unfortunately, the new institutional arrangement and monitoring tools adopted by Hong Kong have not been able to achieve the original intent and neither is there the intention to go too far beyond the weak sustainability approach. On the contrary, Guangzhou has planned and attempted to incorporate industrial ecology in its development regime while heavily investing into pollution control programmes and pushing forward a green community programme at the grass-roots level.  相似文献   
692.

Seven measures of sustainable development for Scotland are examined for the period 1980-1993. These measures are green net national product, genuine savings, ecological footprint, environmental space, human appropriation of net primary production, the index of sustainable economic welfare and the genuine progress indicator. Very different messages concerning sustainable development in Scotland emerge from these measures.  相似文献   
693.
通过对机场运行安全规划中安全指标体系定位的分析,遵循可接受、可实施、可量化、可调控的原则,以结果和过程管理思想为指导,结合风险管理理论,构建机场运行安全规划中的安全指标体系。这个体系包括3个子体系,它们分别涉及运行安全的结果、运行安全的业务过程和运行安全管理绩效3个方面。其中,有关运行安全结果的子指标体系包括事故、事故征候、其他不安全事件3个维度11项指标;有关运行安全业务过程的子指标体系包括飞行区管理、机坪运行管理等7个维度20项指标;有关安全管理绩效的子指标体系包括安全政策与目标、风险管理等4个维度7项指标。  相似文献   
694.
不同波段下黄海中二甲基硫光氧化动力学研究   总被引:1,自引:0,他引:1  
采集黄海表层海水样品,在模拟太阳光照射条件下研究二甲基硫(DMS)在UVB(280、295和305nm)、UVA(320、345和395nm)和可见光(435和495nm)8个不同波段下的光化学氧化动力学行为,并探讨其对二甲亚砜(DMSO)生成的贡献率.研究结果表明,DMS光氧化过程均符合一级反应动力学方程,在UVB、UVA和可见光波段的光氧化速率常数分别为2.71~5.52、2.23~4.09和1.5~2.65d-1.同一样品UVB波段下DMS的氧化速率明显大于UVA和可见光波段下的速率,且在280nm下最大.随着光照时间的增长,海水样品中DMS浓度与有色溶解有机物(CDOM)的光谱吸收系数(α(355))表现出明显的负相关性,表明CDOM吸光特性对DMS的光氧化过程有明显影响.此外,8个不同波段下DMS光氧化向DMSO的转化率在20.0%-31.9%范围之间,其中在280nm下达到最大值.  相似文献   
695.
Since its introduction in the early 1960s, the EU Common Agricultural Policy (CAP) has demonstrated a capacity to adapt and change in the face of new challenges. The reformed CAP, under AGENDA 2000, encourages more environmentally friendly farming practices. In the context of their rural development plans, Member States are required to link policies on agriculture with protection of the environment and to ensure that farmers meet environmental standards. Additionally, Member States should maintain and restore the quality of both their aquatic and adjacent terrestrial ecosystems according to the Directive 2000/60/EU, 'Establishing a framework for Community Action in the field of Water Policy'. Within this framework, agri-environmental indicators play an important role in planning and implementing CAP guidelines. However, selection and use of the proper indicators remains unresolved, considering that ecosystem processes are complex and interactions in most cases not obvious. This paper proposes a methodology for assessing the environmental state and impacts of current land use and management when implementing agri-environmental measures of CAP. The proposed methodology includes a modified Driving forces-Pressures-Impacts-Responses (DPSIR) framework, identification of Zones of Specific Functional Interest (ZSFI), and criteria for selecting agri-environmental indicators, which assess the functional performance of each zone and meet existing legislation. The Mygdonia Watershed (Greece) is an example where through use of both the appropriate Minimum Data Set of agri-environmental indicators at the identified zones and the proposed modified DPSIR, the functioning performance of each ZSFI can be assessed to evaluate the applied agri-environmental measures.  相似文献   
696.
Rail has an important role to play in the development toward a sustainable transportation system. In this perspective, the European Brite Euram Project RAVEL (Rail Vehicle Eco-Efficient Design) has developed a rail sectorwide Design for Environment system to be used and standardized throughout the full supply chain. At the core of the system, quantitative environmental performance indicators for rail vehicles and components are used to incorporate environmental performance target levels in the product requirements and to measure and communicate achieved environmental performance. The concept of eco-efficiency is used to integrate both environmental and economical considerations. The methodology further builds on a standardized material list, standardized data formats, and proactive design guidance. To date, first steps are already taken to integrate the RAVEL project results into sector initiatives toward industrywide acceptance and standardization.Published online Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
697.
The three-dimensional Eulerian model CAMx (Comprehensive Air QualityModel with Extensions) was applied for the first time to simulate bothgaseous and particulate photochemical air pollution in Switzerland during July 28–30, 1993. The meteorological input data were prepared using the Systems Applications International Mesoscale Model (SAIMM). The CAMx model results were compared with the measurements carried out at ground level andfrom airborne measuring platforms within the frame of the Swiss POLLUMET research programme. In general, the CAMx performance for gaseous species wasfound to be better than that of the previously used Urban Airshed Model (UAM)and the Variable Grid Urban Airshed Model (UAM-V). The most significant improvement for the gaseous species is in the prediction of HNO3 concentrations, due to the inclusion of aerosol chemistry. Aerosol species such as NO3 -, NH4 +, SO4 2-, and secondary organic aerosols were calculated in one particle size range (0.04–2.5 m) and compared with a few measurements available. Although July 29 was reasonably well simulated, overestimated wind speeds by SAIMM for July 30 caused a too fast transport of pollutants. Similarly to measurements, significant spatial correlation of the secondarily formed aerosols with ozone and formaldehyde is found in the afternoon.  相似文献   
698.
A frame work was presented for the assessment of the quality of life through the development of different indicators applied for Egypt. This paper focuses on the assessment of the quality of life using previously developed indicators in the first part of the study. A GIS user-friendly interface was developed to enhance the presentation of the study. This enables non technical users to directly use the developed GIS application to explore different concerns. Three cases were demonstrated in this paper, where an assessment of the quality of life of farmers, civilians, and agricultural investors was attained under specific scenario in each case. Assessment for other cases can still be made by browsing through the dropdown menu for each interest group under the selected scenario. Based on the demonstrated results for the three groups of people, it was found that the quality of life for a certain group of people under the strict scenario is in general less than the quality of life for the same group under the relax scenario.  相似文献   
699.
The paper presents a quantitative engineering approach to analysis of total environment allowing for simultaneous consideration of a theoretically infinite number of quality indicators and physiological requirements. It discusses theory and fundamentals of a two-dimensional space and time function solution concerning a small estuarine-type environment. A three dimensional solution is indicated. Input data may range from reconnaissance-type to the outputs of mathematical transport models. Applications are discussed with respect to environmental quality problems, availability of suitable data, and some areas of research where results could find immediate application.  相似文献   
700.
ABSTRACT: A brief review of environmental assessment methods is presented as an introduction to a study of environmental management problems in a coastal area of southern Louisiana. The assessment method used in the study is called suitability analysis and involves the use of matrices. The matrix approach is simply a convenient method for organizing all factors representing environmental concerns in a region. The matrices proved to be very useful in defining the present state of an environmental regime and in maintaining an inventory of regional features and potential impacts. The method is described in detail and illustrated by evaluating the potential impacts of a major pipeline construction job in the area. Of major concern is the potential impact on the water resources of the region. Disruption to the natural drainage could be detremental, and affect the suitability of available water for a given use. Limitations of the method are discussed and potential areas for improvement and research are noted. Coupled with an economic assessment, the suitability analysis method should prove beneficial for selecting development sites for industries, residential areas, and other construction activities.  相似文献   
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