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1.
大气甲醛(HCHO)是臭氧(O3)和细颗粒物(PM2.5)二次组分的关键前体物,在大气光化学反应和二次污染形成过程中扮演着重要角色,并存在致癌性.然而,当前对大气HCHO排放来源认识存在不足,制约了二次污染形成机制研究和污染防控策略制定.采用排放因子和成分谱结合方法,建立2006~2020年广东省HCHO排放趋势清单,识别了广东省主要HCHO排放来源和排放时空演变特征.结果表明,2006~2020年期间广东省HCHO排放量在3.9~5.6万t区间波动,整体呈现极微弱的下降趋势;生物质燃烧源是广东省重要HCHO排放源,而受到管控措施的显著影响,其排放量占比从2006年的58%降至2020年的27%;溶剂使用源的HCHO排放则逐渐突显,2020年占比增长至28%,并成为广东省首要排放源,其中塑料制品和沥青铺路是主要贡献行业.移动源中以柴油作为燃料的工程机械和货车也是HCHO重要排放来源;虽然珠三角和非珠三角地区对广东省HCHO排放量贡献相当,但空间分布结果表明HCHO排放热点区域分别集中于珠三角中心区域和非珠三角的东西两角,这是由于珠三角主要来源为溶剂使用源和移动源,而非珠三角主要受生物质燃烧源影响.因此,未来应进一步加强珠三角中心区域的工业和移动源减排以及粤西地区的生物质燃烧监管.  相似文献   
2.
基于中国资源型城市2003—2018年面板数据综合测度城市转型绩效,采用空间马尔科夫链、空间计量模型和空间双重差分模型,探究资源型城市转型绩效特征及其对碳排放的影响。结果表明:(1)资源型城市转型绩效逐渐提升,与此对应的是区域差异呈波动上升趋势,且四种类型资源型城市之间区域差异主要来源于地区内差异,成熟型城市贡献最大;资源型城市转型绩效存在明显的空间分异性,发展格局由以跨越区为核心的“多点式”零星分布向先行区为核心的“组团式”聚集形态演变。(2)资源型城市转型绩效在不同时期存在状态转移的可能性,具有滞后区、起步区、跨越区和先行区4个趋同俱乐部特征,空间马尔科夫链表明转移趋势存在明显空间关联性,状态转移通常出现在相邻等级之间,较少有“跳跃式”转移现象,具有长期性和持续性特征。(3)资源型城市转型具有显著碳减排效应,而且这种效应存在不同资源类型、不同发展阶段和不同空间区位的异质性特征,经济产业转型、社会生活转型和生态环境转型是发挥碳减排效应的重要因素;进一步的政策冲击分析表明,产业转型升级示范区和高新技术产业开发区的设立对城市碳减排具有积极的政策效应。  相似文献   
3.
In this paper, the life span of hydro and nuclear energy generations and the relationship between hydro and nuclear energy generations, environmental pollution, and economic growth were investigated for Japan covering the period of 1960–2018 by employing the Bathtub-Weibull curve and Markov switching-vector error correcting (MSVEC) method, respectively. According to the Bathtub-Weibull curve analysis, a rising failure rate for nuclear energy was found, indicating that the life of nuclear energy has expired, but a decreasing failure rate for hydroelectric energy has been detected. Then two different MSVEC models were used. The MSVEC method, unlike traditional approaches, determines the relationship between variables under different regimes. The results of MSVEC methods indicate three important points. First, regime-dependent asymmetry and regime changes are crucial for policy recommendations. Second, the shocks to hydropower and nuclear energy generations cause temporary deviations from the long-run growth path in both regimes. Lastly, the increase in hydropower generation leads to a decrease in environmental pollution and an increase in GDP, and an increase in nuclear power generation increases pollution and growth in both regimes.  相似文献   
4.
本文以江苏省为研究区域,采用1990—2013年江苏省市级面板数据,基于单位根检验和面板协整检验,运用可拓展的随机性环境影响评估模型(STIRPAT)和参数、半参数固定效应回归方法,对经济增长与工业COD排放之间的关系展开研究。研究发现,江苏省经济增长与工业COD排放之间存在倒U形曲线关系,即全省工业COD排放随经济的发展呈现先增长后降低的趋势,同时人口增长对水污染物排放影响很大,二者之间的环境库兹涅茨曲线表明了经济持续发展能够协调并能解决其与水污染排放之间的困境。本研究丰富了社会经济发展与水污染关系在市级尺度层面的实证研究,为"十三五"期间江苏省水污染治理提供了政策依据。  相似文献   
5.
We exploit recent advances in climate science to develop a physically consistent, yet surprisingly simple, model of climate policy. It seems that key economic models have greatly overestimated the delay between carbon emissions and warming, and ignored the saturation of carbon sinks that takes place when the atmospheric concentration of carbon dioxide rises. This has important implications for climate policy. If carbon emissions are abated, damages are avoided almost immediately. Therefore it is optimal to reduce emissions significantly in the near term and bring about a slow transition to optimal peak warming, even if optimal steady-state/peak warming is high. The optimal carbon price should start relatively high and grow relatively fast.  相似文献   
6.
Sustainable use of natural resources would entail ensuring that derived economic benefits today do not undermine the welfare of generations to come. On this basis, this study examines the nexus between natural resource rents and carbon dioxide (CO2) emissions disaggregated into production and consumption-based (i.e., trade-adjusted) CO2 emissions for a selected panel of 45 developing and transition economies over the period 1995–2017. The empirical model also incorporates the impacts of population, affluence, and energy intensity. The results show that affluence increases production-based CO2 emissions by 1.407%, with the EKC's predicted inverted U-shaped curve only explaining consumption-based CO2 emissions. Economic reliance on natural resource rents and energy intensification contribute 0.022% and 0.766%, respectively, to CO2 emissions embedded in territorial production inventories and 0.035% and 0.583%, respectively, to CO2 emissions embedded in consumption inventories. The bootstrap non-causality test shows that historical data on each variable has significant predictive power for future CO2 emissions from both sources. The historical information about natural resource rents has significant predictive power over the future levels of affluence and energy intensity. Clearly, the results show that the environmental impact of natural resource rents is stronger when CO2 emissions are adjusted for trade and varies among the countries, with Bangladesh, Guinea, India, Malaysia, Mexico, Nigeria, Pakistan, Saudi Arabia, Vietnam, and Zimbabwe among the most affected countries. Overall, this study provides motivation for policies to keep the use of natural resources within sustainable limits.  相似文献   
7.
作为全球气候治理的重要手段,碳排放交易制度受到了广泛的关注与讨论。基于此,本文采用我国2010-2016年城市面板数据,运用非参数方法构建方向性环境距离函数测算了2009-2015年城市减排的机会成本,计算结果显示,试点地区与非试点地区的碳排放的机会成本整体表现为上升的趋势,且试点地区的碳排放的机会成本总体低于非试点地区。在测算城市减排机会成本的基础上,运用双重差分法来检验碳排放交易制度的有效性。经检验发现:碳排放交易制度有利于降低城市减排的机会成本,然而由于碳排放交易制度还存在碳排放权初始分配制度缺失、碳排放交易制度的定价机制扭曲等问题,因此其对降低城市减排的机会成本作用较小,并且进一步通过对政策时间趋势的分析得出政策效应随时间推移而逐渐减弱。  相似文献   
8.
Global greenhouse gas emissions from air travel (GHG-A) are on the rise, and projections point towards a rapid growth in the coming decades. This study aims to examine how local government (cities), addresses GHG-A in their Sustainable Energy Action Plans (SEAP). To fulfil this aim, over 200 SEAPs were analysed focusing on three issues: (1) Treatment of GHG-A in local emissions inventories; (2) Policy initiatives within this domain; and (3) The cities’ perceptions of the conflicts of interests. Results showed that more than half of the cities acknowledge the challenge of GHG-A, around one third include GHG-A in their emissions inventories, and more than one quarter have initiated policy interventions. To categorise these interventions, we have added a mode ‘governing by agenda setting’ to an existing analytical framework, ‘Modes of governing’. With their authority limited to the local setting, this mode of governing is a common channel for cities to push changes at higher levels.  相似文献   
9.
Global warming is negatively affecting the environment of the planet. This situation has led to the development of international standards, such as the International Organisation for Standardization's DIS 14064‐1 and the Greenhouse Gas Protocol Corporate Standard, both of which measure corporate carbon footprints. These standards provide guidelines that can be applied to different organizational sectors. However, these are not sufficient for controlling the reduction of carbon emissions, because although they propose the use of indicators, they do not explicitly define them. In addition, in the case of emissions from wastewater treatment, they only suggest that the emissions associated with this process be considered. In the present study, an eight‐step, unified methodology based on these two international standards is proposed, focusing on direct emissions. Moreover, the step‐by‐step to data collection, calculations, and the required indicators to control the emissions are defined. The first scope considers direct emissions from sources that are owned or controlled by the company. Methane generation measurement from wastewater treatment has been included in the methodology within Scope 1, as it is the second most polluting gas after carbon dioxide, both of which give rise to global warming. The proposed methodology was tested as a case study in one of the most important companies in the food sector in Colombia.  相似文献   
10.
Worldwide energy demand has been growing steadily during the past five decades and most experts believe that this trend will continue to rise. The amount of emitted harmful emission gases increases in parallel with increasing energy consumption. This increase has forced many countries to take various precautions, and various restrictions on emitted emissions have been carried. In this study, effects of addition of oxygen containing nanoparticle additives to biodiesel on fuel properties and effects on diesel engine performance and exhaust emissions were investigated. Two different nanoparticle additives, namely MgO and SiO2, were added to biodiesel at the addition dosage of 25 and 50 ppm. Fuel properties, engine performance, and exhaust emission characteristics of obtained modified fuels were examined. As a result of this study, engine emission values NOx and CO were decreased and engine performance values slightly increased with the addition of nanoparticle additives.  相似文献   
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