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41.
Evaluation of ambient air quality in Guangzhou, China   总被引:5,自引:0,他引:5  
On the basis of the reported air quality index (API) and air pollutant monitoring data provided by the Guangzhou Environment Monitoring Stations over the last twenty-five years, the characteristics of air quality, prominent pollutants, and variation of the average annual concentrations of SOE, NOE, total suspended particulate (TSP), fine particulates (PM10), CO and dustfall in Guangzhou City were analyzed. Results showed that TSP was the prominent pollutant in the ambient air environment of Guangzhou City. Of the prominent pollutants, TSP accounted for nearly 62%, SOE 12.3%, and NOx 6.4%, respectively. The average API of Guangzhou over 6 years was higher than that of Beijing, Tianjin, Nanjing, Hangzhou, Suzhou and Shanghai, and lower than that of Shenzhen, Zhuhai and Shantou. Concentrations of air pollutants have shown a downward trend in recent years, but they are generally worse than ambient air quality standards for USA, Hong Kong and EU. SOE and NOx pollution were still serious, impling that waste gas pollution from all kinds of vehicles had become a significant problem for environmental protection in Guangzhou. The possible causes of worsening air quality were also discussed in this paper.  相似文献   
42.
利用沈阳、鞍山、抚顺和本溪4城市2007-2009年大气细粒子PM2.5及大气污染物PM10SO2、NO2的观测资料,分析了4城市大气细粒子的分布特征及其与空气质量的关系.结果表明:4城市大气细粒子PM2.5污染很重,年均浓度平均值超过美国大气细粒子PM2.5年均浓度标准4倍左右;4城市PM10、SO2的年均浓度呈下降...  相似文献   
43.
ABSTRACT

This article analyzes the emergence of a new environmental issue in the German press. Since the 1990s, scientists have detected traces of pharmaceuticals, hormones and chemicals in all segments of the water cycle. These micropollutants have negative effects on aquatic life and might affect human health. Their sources are manifold and include private households. Yet although micropollutants of are direct concern to media audiences, they are a challenging topic for news reporting. Although this issue is systemic and fraught with uncertainty, it does not easily translate into news stories. Our content analysis of 444 articles (1995–2015) reveals that the societal risk was rarely presented as a stand-alone topic. Instead, the issue was mostly covered as part of local routine reporting and framed as a challenge for experts to solve. Over time, the reporting became more managerial, while media framings of micropollutants gained more substance and scope. We contend that local routine reporting should receive more attention as a public forum for addressing emerging environmental concerns.  相似文献   
44.
Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
45.
This paper aims to identify the positive and negative aspects in the sustainability reporting framework proposed by the Global Reporting Initiative (GRI). The research was conducted through content analysis of 27 companies’ responses to three questions: “Why does the company where you work prepare a sustainability report?” “What are the positive aspects you identify in the framework for GRI reporting?” and “What are the negative aspects you identify in the framework for GRI reporting?” The questionnaire was sent to all Brazilian companies that published sustainability reports using the GRI guidelines between 2011 and 2013 related to the base year 2010. We found that respondents viewed the GRI guidelines and the reports they created as management tools for sustainability and that they assist in benchmarking sustainability performance and legitimizing the sustainability actions of the organization. Furthermore, some respondents indicated that the reports themselves are marketing tools. On the other hand, the respondents reported difficulties in understanding the proposed GRI guidelines. They considered the guidelines complex, ambiguous, and too flexible, which undermined both the standardization of the reports and the ability to compare reports. Based on these comments, it is recommended that the GRI develop a simpler and less flexible reporting methodology.  相似文献   
46.
In a world where companies have major influence over the economy, politics, and environment, they must be held accountable for their actions. With this in mind, the publication of sustainability reports is in a company’s best interest, since the disclosure of Corporate Social Responsibility (CSR) and sustainable practices can bring enormous advantages, largely related to a company’s image. The amount of information presented in sustainability reports turns them into valuable sources for research data, allowing analyses related to CSR and management practices, stakeholder relations, language used, among others. However, there is no a paper in the literature that analyzes theses information jointly for the Brazilian companies, and then we decided to explore this theme. This research aimed to identify advances and gaps of CSR practices performed by Brazil companies, through the analysis of 30 sustainability reports published between 2014 and 2015. The main findings indicate that, in general, the analyzed companies are experienced in sustainability reporting; however, there is still room for improvements, including a better mapping and reporting of practices involving the integration of CSR to organizational structure, stakeholder engagement, and continuous improvement practices.  相似文献   
47.
为提高地铁施工阶段险兆事件自愿上报水平,研究地铁施工阶段险兆事件自愿上报意愿的影响因素,通过文献查阅和访谈等方法归纳出险兆事件自愿上报意愿的影响因素,建立险兆事件自愿上报意愿指标体系。基于组合赋权法计算的权重对各指标进行重要性排序,并提出提高险兆事件自愿上报水平的对策建议。结果表明:认知水平、未对上报者和当事人保密、存在责备及苛责文化和无惩罚制度没有充分落实是地铁施工阶段险兆事件自愿上报意愿的关键影响因素。  相似文献   
48.
Given the complexity and time-consuming of the conventional environmental capacity based assessment on air environment carrying capacity; a new method for assessing urban air environment carrying capacity based on air pollution index (API) is presented. By using this new method, the air environmental bearing capability of 333 cities at the prefecture level and above is assessed. The results show that of the 333 cities 9.6% is of high bearing capability, 34.5% relatively high bearing capability, 52.6% medium bearing capability, 2.7% low capability, and 0.6% is of weak bearing capability; in terms of regional distribution, the western region is of relatively high air environment bearing capability, followed by north-eastern and eastern regions, and the ambient air quality in the middle region is quite poor; among the 12 urban agglomerations in key regions, Pearl River delta, west side of Taiwan Strait and Chengdu-Chongqing agglomerations are of relatively high carrying capacity while other agglomerations are of medium bearing capability. The assessment results imply that the existing air quality standard (GB3095-1996) is quite unsound.  相似文献   
49.
对南宁市2003年的空气污染指数(API)与天气因素(天气类型、气象因子)的相关性进行了详细分析。结果表明,高压脊在冬春季对API影响较大;低压槽、副热带高压在夏秋季对API影响较大。湿度、云量与API呈相反走势,而温度则与API相关性不大。  相似文献   
50.
Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, the United States and other countries are implementing, by themselves or in cooperation with one or more other nations, climate change projects. These projects will reduce greenhouse gas (GHG) emissions or sequester carbon, and will also result in non-GHG benefits (i.e., environmental, economic, and social benefits). Monitoring, evaluating, reporting, and verifying (MERV) guidelines are needed for these projects to accurately determine their net GHG, and other, benefits. Implementation of MERV guidelines is also intended to: (1) increase the reliability of data for estimating GHG benefits; (2) provide real-time data so that mid-course corrections can be made; (3) introduce consistency and transparency across project types and reporters; and (4) enhance the credibility of the projects with stakeholders. In this paper, we review the issues involved in MERV activities. We identify several topics that future protocols and guidelines need to address, such as: (1) establishing a credible baseline; (2) accounting for impacts outside project boundaries through leakage; (3) net GHG reductions and other benefits; (4) precision of measurement; (5) MERV frequency and the persistence (sustainability) of savings, emissions reduction, and carbon sequestration; (6) reporting by multiple project participants; (7) verification of GHG reduction credits; (8) uncertainty and risk; (9) institutional capacity in conducting MERV; and (10) the cost of MERV.  相似文献   
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