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841.
Strategic environmental assessment (SEA) inherently needs to address greater levels of uncertainty in the formulation and implementation processes of strategic decisions, compared with project environmental impact assessment. The range of uncertainties includes internal and external factors of the complex system that is concerned in the strategy. Scenario analysis is increasingly being used to cope with uncertainty in SEA. Following a brief introduction of scenarios and scenario analysis, this paper examines the rationale for scenario analysis in SEA in the context of China. The state of the art associated with scenario analysis applied to SEA in China was reviewed through four SEA case analyses. Lessons learned from these cases indicated the word “scenario” appears to be abused and the scenario-based methods appear to be misused due to the lack of understanding of an uncertain future and scenario analysis. However, good experiences were also drawn on, regarding how to integrate scenario analysis into the SEA process in China, how to cope with driving forces including uncertainties, how to combine qualitative scenario storylines with quantitative impact predictions, and how to conduct assessments and propose recommendations based on scenarios. Additionally, the ways to improve the application of this tool in SEA were suggested. We concluded by calling for further methodological research on this issue and more practices.  相似文献   
842.
Fan Li  Tao Zhou  Lin Wang 《Disasters》2021,45(1):180-201
This study performed a comparative analysis of changes in the operating status of initial surviving disaster‐stricken businesses and non‐disaster‐stricken businesses in Lushan County, China, after a devastating earthquake on 20 April 2013. It used a logistic regression model to explore the key factors associated with ‘post‐disaster continued business operation’ in the long term. Field data were collected from 1,078 businesses and questionnaire data from 263 small businesses between 2013 and 2017. The results indicate that a higher proportion of initial surviving disaster‐stricken businesses than non‐disaster‐stricken businesses managed to remain operational in each observation period. The continued operation of disaster‐stricken businesses after the earthquake was positively associated with the owner's age, previous disaster experience, pre‐disaster financial conditions, closure duration, and borrowing money from family or friends. A negative association was found with the size of the business. The findings serve as a vital reference for strategies to promote post‐disaster continued business operation.  相似文献   
843.
能源燃烧产物是PM2.5暴露水平提高的重要因素,燃烧不同种类的能源对PM2.5形成的影响机理不同,但各类能源消耗量对人群PM2.5暴露水平的影响程度尚不明确.基于2003-2010年的PM2.5质量浓度与煤炭、焦炭、原油、汽油、煤油、柴油、燃料油、天然气和电力消耗数据组成的面板数据,建立了不同种类能源消耗影响我国人群PM25暴露水平的随机效应模型.结果表明,我国2003-2010年多数省(市、自治区)的年均PM2.5质量浓度超过了世界卫生组织的标准.在研究时间段内,不同种类能源消耗量对人群PM2.5暴露水平的影响具有较大差异,煤炭、焦炭、汽油和煤油消耗对人群PM2.5暴露水平具有正影响,其中,正向影响最大的为焦炭消耗量,表明工业消耗焦炭对形成PM2.5的促进作用比较明显;与焦炭消耗量具有相近的影响效果的因素是汽油消耗,表明改进机动车和航空燃油技术同样非常重要;原油、柴油、燃料油、天然气和电力消耗对人群PM2.5暴露水平具有负影响,其中负向影响最大的为电力消耗量,表明电力作为一种清洁能源,有利于降低人群PM2.5暴露水平.  相似文献   
844.
简要统计了2015年5-6月国内发生的各种环境事件118起,包括沙尘天气7起,污染事件14起,地震40起,山体滑坡和泥石流25起,旱灾2起以及其他自然灾害30起.  相似文献   
845.
The secondary tropical forests in southern China have suffered from frequent human disturbance and increasing high N deposition. In order to explore the nutrient limitation status in secondary tropical forests of South China, this 3-year field experiment of nitrogen (+N) and phosphorus (+P) addition investigated nitrogen (N) and phosphorus (P) concentrations of the aboveground tissue (leaf and branch) of two widely distributed understory native species Clerodendrum cyrtophyllum and Uvaria microcarpa in a secondary tropical forest of South China. The results showed that: 1) the N and P concentrations of the two species were significantly different (P < 0.001); N and P concentrations of different tissues in the same species were different; N&P addition greatly affected N and P concentrations in branch rather than new leaf and older leaf. 2) +N treatment had no significant effect on N or P concentrations of either species, but significantly decreased N:P ratios (P = 0.001), at the level of 9% for C. cyrtophyllum and 50% for U. microcarpa, respectively. 3) +P treatment had no significant effect on tissue N concentrations, but significantly increased plant P concentrations (P < 0.001), at 54% for C. cyrtophyllum and 88% for U. microcarpa, respectively; +P treatment significantly decreased plant N:P ratios (P < 0.001), at 28% and 60%, respectively. 4) The alterations of P concentrations of two species had significantly negative correlations with N:P alterations under +N/+P treatment (P < 0.001), suggesting that the alteration of P concentrations in plant tissue was the major driver for N:P alteration. Our results show that N and P addition would affect tissue N and P concentrations of the two species, with +P treatment having relatively greater effect on nutrient concentrations than +N treatment; the branch is more sensitive than new or older leaf in response to nutrient addition. Therefore, P availability may be the limiting factor for plant growth in the tropical forests.  相似文献   
846.
Large-scale incinerators are applied widely as a result of the heavy burden of municipal solid waste(MSW) generated, while strong opposition is arising from the public living nearby. A large-scale working incineration plant of 1500 ton/day was chosen for evaluation using life cycle assessment. It was found that the corresponding human toxicity impacts via soil(HTs), human toxicity impacts via water(HTw) and human toxicity impacts via air(HTa)categories are 0.213, 2.171, and 0.012 personal equivalents(PE), and global warming(GW100)and nutrient enrichment(NE) impacts are 0.002 and 0.001 PE per ton of waste burned for this plant. Heavy metals in flue gas, such as Hg and Pb, are the two dominant contributors to the toxicity impact categories, and energy recovery could reduce the GW100 and NE greatly. The corresponding HTs, HTw and HTa decrease to 0.087, 0.911 and 0.008 PE, and GW100 turns into savings of- 0.007 PE due to the increase of the heating value from 3935 to5811 k J/kg, if a trommel screener of 40 mm mesh size is used to pre-separate MSW. MSW sorting and the reduction of water content by physical pressure might be two promising pre-treatment methods to improve the combustion performance, and the application of stricter standards for leachate discharge and the flue gas purification process are two critical factors for improvement of the environmental profile identified in this work.  相似文献   
847.
Volatile organic compounds (VOCs) are crucial to control air pollution in major Chinese cities since VOCs are the dominant factor influencing ambient ozone level, and also an important precursor of secondary organic aerosols. Vehicular evaporative emissions have become a major and growing source of VOC emissions in China. This study consists of lab tests, technology evaluation, emissions modeling, policy projections and cost-benefit analysis to draw a roadmap for China for controlling vehicular evaporative emissions. The analysis suggests that evaporative VOC emissions from China's light-duty gasoline vehicles were approximately 185,000 ton in 2010 and would peak at 1,200,000 ton in 2040 without control. The current control strategy implemented in China, as shown in business as usual (BAU) scenario, will barely reduce the long-term growth in emissions. Even if Stage II gasoline station vapor control policies were extended national wide (BAU + extended Stage II), there would still be over 400,000 ton fuel loss in 2050. In contrast, the implementation of on-board refueling vapor recovery (ORVR) on new cars could reduce 97.5% of evaporative VOCs by 2050 (BAU + ORVR/BAU + delayed ORVR). According to the results, a combined Stage II and ORVR program is a comprehensive solution that provides both short-term and long-term benefits. The net cost to achieve the optimal total evaporative VOC control is approximately 62 billion CNY in 2025 and 149 billion CNY in 2050.  相似文献   
848.
Coal combustion and mercury pollution are closely linked, and this relationship is particularly relevant in China, the world's largest coal consumer. This paper begins with a summary of recent China-specific studies on mercury removal by air pollution control technologies and then provides an economic analysis of mercury abatement from these emission control technologies at coal-fired power plants in China. This includes a cost-effectiveness analysis at the enterprise and sector level in China using 2010 as a baseline and projecting out to 2020 and 2030. Of the control technologies evaluated, the most cost-effective is a fabric filter installed upstream of the wet flue gas desulfurization system (FF + WFGD). Halogen injection (HI) is also a cost-effective mercury-specific control strategy, although it has not yet reached commercial maturity. The sector-level analysis shows that 193 tons of mercury was removed in 2010 in China's coal-fired power sector, with annualized mercury emission control costs of 2.7 billion Chinese Yuan. Under a projected 2030 Emission Control (EC) scenario with stringent mercury limits compared to Business As Usual (BAU) scenario, the increase of selective catalytic reduction systems (SCR) and the use of HI could contribute to 39 tons of mercury removal at a cost of 3.8 billion CNY. The economic analysis presented in this paper offers insights on air pollution control technologies and practices for enhancing atmospheric mercury control that can aid decision-making in policy design and private-sector investments.  相似文献   
849.
多溴联苯醚(Polybrominated diphenyl ethers, PBDEs)为一类新型的溴代阻燃剂,广泛应用于塑料制品、纺织品、电路板和建筑材料等领域。随着生产量和使用量的增加,PBDEs已造成全球环境污染,其带来的环境问题已引起各国关注。同时PBDEs的长距离迁移性和难降解性,使其在环境介质中进行富集,从而加重污染。归纳了中国地区PBDEs的监测进展,分别从大气、水体、沉积物和土壤中PBDEs的污染水平以及原因进行了分析和探讨。在此基础上,对于我国PBDEs的研究方向提出了展望。  相似文献   
850.
在分析南湖水质的基础上,对重金属进行Pearson相关性分析,并进行了健康风险评价。结果表明Cr、Cu、Zn未超过生活饮用水卫生标准,Cd 和Pb严重超标。 Cu、Zn、Cd、Cr污染存在一定的同源性,而Mn、Fe、Ni、Pb污染具有多源性。污染物通过皮肤接触途径造成的危害要远小于饮水途径,致癌物风险比非致癌物高1~8个数量级,其中Cd对总风险贡献率为62.16%,成为主要的风险污染物。8个监测点都检测到致癌物,且风险度高于可接受水平,应引起环境治理部门的关注。  相似文献   
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