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691.

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   
692.
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   
693.
尿液、头发、指(趾)甲高铊汞砷是铊矿区污染标志   总被引:8,自引:0,他引:8       下载免费PDF全文
铊矿区村民尿液、头发和指(趾)甲中铊汞砷的含量高是矿区和村民受铊汞砷污染的标志,也是判别汞铊病的标志根据村民尿液中铊含量高低初步得出区别不同程度汞铊病患者的标准TL>1000×10-9、100×10-9-1000×10-9和<100×10-9分别为重汞铊病患者、轻汞铊病患者和非汞铊病者。人体和生物体中TL、Hg、As含量高低与矿区岩矿石、土壤和水体中TI、Hg、As的背景含量密切相关  相似文献   
694.
苯并(a)芘致毒的鱼的分子生态毒理学指标研究   总被引:11,自引:1,他引:10       下载免费PDF全文
通过测定典型的多环芳烃类物质苯并(a)芘(BaP)致毒后鱼体内几种重要分子生态毒理学指标的变化,来反映苯并(a)芘致毒对鱼体的影响.结果表明,肝脏ATPase活性降低,GST活性升高,DNA加合物相对标记水平(RAL)也增大,而EROD活性没有明显改变.这说明苯并(a)芘致毒对鱼体正常生命活动产生了重大影响,并具有潜在的致癌性.  相似文献   
695.
Despite the widespread field and laboratory research works there are still a lot of unknown aspects about the cold in-place recycling. This paper presents the outcomes of a five year evaluation of a major highway in Iran which had been rehabilitated by cold in-place recycling. Before starting the rehabilitation process, a comprehensive field survey was performed. During the pavement surveying, type, severity and reason of distresses were investigated and PCI parameter was calculated. Furthermore, both destructive and nondestructive tests were carried out to evaluate the pavement condition and estimate the remaining life. On the basis of these investigations studied highway was divided to six design sections. Based on technical analysis four sections were recycled whereas two other sections were rehabilitated with the conventional cold milling and overlay method. Afterwards, the pavement performance was monitored during the next 5 years. After about six months of monitoring, structural failures were detected in about 10% of recycled areas. Based on field surveying, low compaction and load bearing of subgrade materials and lack of high quality unbound pavement layers accompanied by some shortcomings in recycled layer resulted in undesirable results in these areas. Based on obtained results and performed analysis a practical flowchart was presented which could be used as a project selection guideline.  相似文献   
696.
将29个煤电项目验收监测核算的二氧化硫排放总量与环保行政主管部门批复的总量控制指标作对比,从运行负荷、脱硫效率、燃煤煤质等方面分析了二者数值存在较大差异的原因。建议在验收监测期间要求企业按环评设计值控制各项参数,并将验收监测总量核算结果作为排污许可或日常监管的参照,进一步强化总量核查与总量控制,推行排污许可证制度。  相似文献   
697.
为了增强自然保护区内和保护区间的生态系统质量评估结果的可比性,基于“理想参照系和关键指标”的理念,提出量化关键指标阈值和生态系统质量的算法,并以额尔古纳、辉河和锡林郭勒国家级自然保护区为例开展具体的评估工作。研究发现:(1)额尔古纳保护区生态系统质量指数(84.59)显著高于辉河(69.26)和锡林郭勒保护区(63.41)。(2)三个保护区不同功能区间的生态系统质量指数无显著差异。(3)2000—2018年,额尔古纳和锡林郭勒保护区的生态系统质量指数均呈显著上升趋势,但辉河保护区无明显变化。本文提出的评估方法能科学、快速地评估自然保护区生态系统质量现状及变化,可量化其恢复潜力,并能实现评估结果间的比较,为保护区建设和管理提供参考。  相似文献   
698.
The performance evaluation of integrity management has become the focus of attention because integrity management has become widely accepted by pipeline operators. This paper proposes a three-index system of pipeline integrity management performance evaluation (TISPIMPE), which includes system construction, implementation process, and pipeline health status, comprehensively evaluating the status, adequacy, and effectiveness of integrity management. It helps the pipeline operators to determine the weakness in each step. Based on the improved analytic hierarchy process (AHP), the different backgrounds of experts are fully considered, and experts' opinions are revised. The adjustment coefficient of performance evaluation is set up simultaneously, and the evaluation results are adjusted to make the results more reasonable. Taking the performance evaluation of pipeline integrity management of an oil and gas company as an example, it is shown that TISPIMPE has reasonable practicability and can accurately reflect the shortcomings of pipeline integrity management. TISPIMPE can effectively help pipeline managers comprehensively and systematically evaluate the performance of pipeline integrity management and gain an in-depth understanding of pipeline operation status.  相似文献   
699.
水环境质量评价是水资源可持续利用的重要前提,同时也是水环境管理与治理决策的重要依据。为科学评价黄河呼和浩特段水环境质量,基于基础资料数据库,遵循全面性、区域性、易量化性等原则,采用综合污染指数法详细分析了黄河呼和浩特段水环境质量的时空变化情况,进一步揭示了2020年水质季节变化规律,并对主要超标因子进行了深度解析。结果表明:随着一系列环境保护政策和管理措施的实施,2015—2020年黄河呼和浩特段水环境质量综合指数下降了75.87%。在时间尺度上,各断面的水环境质量综合指数平均值由2015年的93.81下降至2020年的22.64,整体水环境质量评价等级由G4转为G2,对应的水环境质量状况由中度污染转为较好;在空间尺度上,上游水环境质量优于下游,城区段水环境质量较差。此外,评价结果显示,部分水体当前仍存在氨氮超标问题。评价结果较为客观地反映了黄河呼和浩特段的水环境质量,可为水环境管理提供决策依据。  相似文献   
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