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51.
张宁  庞军  温婧  王军霞 《中国环境科学》2022,42(5):2442-2452
通过构建电力部门细分的CGE模型,分别在电价管制和完全竞争市场背景下,评估了取消电价交叉补贴和可再生能源电价补贴,以及引入碳税政策并将碳税收入转移支付给风电及光伏行业的经济影响.研究发现:取消电价交叉补贴对GDP有负面影响,而取消可再生能源电价补贴后GDP有所提升;相比完全竞争市场,电价管制市场背景下取消电价交叉补贴对GDP的负面冲击强度增加了0.003%,而取消可再生能源电价补贴对GDP的促进作用幅度则相对减小0.056%;同时取消两种补贴时,在电价管制市场背景下GDP相比基准情景下降了0.022%,而在完全竞争市场背景下GDP则增加了0.038%.电价管制市场背景下取消电价补贴对电力结构及能源结构影响较小;而在完全竞争市场背景下取消电价补贴将刺激传统电力消费并导致碳排放有所增加.引入碳税政策并将碳税收入转移支付给风电及光伏行业可以有效控制碳排放并促进电力结构和能源结构改善,但会对行业总产出和GDP产生更大的负面冲击.我国未来应适度放开电价管制,并采取诸如适时征收碳税并将其收入转移支付给风电和光伏行业的支持性政策,推动我国能源结构优化和节能减排目标的实现.  相似文献   
52.
近年来,海洋微塑料污染已成为全球关注的重要环境问题。海洋中广泛存在的微塑料可被藻类吸附、微生物定植,亦可被海洋动物摄食并蓄积。生物与微塑料之间的相互作用必然会改变微塑料的物理、化学性质,及其在海洋中的迁移转化。因此,本文系统地阐述了海洋生物对微塑料的吸附、摄入、蓄积与排泄等关键过程;重点总结了微塑料在海洋生物过程(如排泄、与海洋雪团聚、形成生物膜以及生物扰动)影响下的沉降-埋藏等迁移过程;深入讨论了海洋动物对微塑料的摄食、消化过程以及微生物的分解作用导致的微塑料破碎、降解以及塑料添加剂和吸附污染物的释放过程及其机理。本文阐明了海洋生物对微塑料迁移转化的调控作用,为理解海洋微塑料的环境归趋提供理论依据。  相似文献   
53.
Most probable number (MPN) and colony-forming unit (CFU) estimates of fecal indicator bacteria (FIB) concentration are common measures of water quality in aquatic environments. Thus, FIB intensively monitored in Yeongsan Watershed in an attempt to compare two di erent methods and to develop a statistical model to convert from CFU to MPN estimates or vice versa. As a result, the significant di erence was found in the MPN and CFU estimates. The enumerated Escherichia coli concentrations in MPN are greater than those in CFU, except for the measurement in winter. Especially in fall, E. coli concentrations in MPN are one order of magnitude greater than that in CFU. Contrarily, enterococci bacteria in MPN are lower than those in CFU. However, in general, a strongly positive relationship are found between MPN and CFU estimates. Therefore, the statistical models were developed, and showed the reasonable converting FIB concentrations from CFU estimates to MPN estimates. We expect this study will provide preliminary information towards future research on whether di erent analysis methods may result in di erent water quality standard violation frequencies for the same water sample.  相似文献   
54.
海岸带环境综合管理问题探讨   总被引:1,自引:0,他引:1  
目前,中国海岸带环境管理中存在的法律、组织协调和运行机制等现有主要问题;福建省海岸带环境管理中存在的主要问题,提出了调整海洋环境功能区划、建立海洋污染事故快速反应体系与应急联动处置机制、加快城市排海污水处理能力的规划与建设、规范海水养殖功能区的管理、加强污染物排海总量控制技术与政策研究、实施海湾区域开发规划环境影响评价、实施海陆一体化的海岸带环境综合管理等福建省海岸带环境综合管理的调控措施.  相似文献   
55.
中国民航局提出持续安全理念,并正在制定国家航空安全方案,推动行业安全管理由目前基于规章符合性的安全监管逐渐转向规章符合性基础上的安全绩效监管,其中一项重要的工作是设定中国民航业可接受的安全水平,来衡量民航业是否满足持续改进安全的目标的要求。本文根据国际民航组织对可接受安全水平的设定指南,同时参考国外民航常用的事故指标,设计了一套中国民航行业可接受安全水平的指标体系,该指标体系包括安全评估指标、安全绩效评估指标和安全指数三层,并对该指标体系内事故率指标和事故征候率指标设定了未来10年的目标值。该指标体系及其目标值的设定不仅可作为衡量民航是否持续安全的标准,也可为航空运输企业设定自身的安全绩效考核指标提供参考。  相似文献   
56.
从安全生产作为一种"公共产品"的视角,分析中小企业供给与需求状况,得出目前中小企业安全生产处于"供给低、需求低"的非正常状态,说明劳动力市场对安全供求的调节已经失灵;通过对安全管制下中小企业日常安全管理行动的调研,结合相关研究成果,说明中小企业安全生产管制存在"管制失灵";对安全生产管制存在的问题进行分析,并提出以完善安全生产法律法规体系为前提,以加强中小企业安全生产监管信息库建设为基础,以建立和完善中小企业安全生产三大机制为手段将中小企业安全生产引入良性发展轨道。  相似文献   
57.
用经济学分析工具对现有的职业健康规制进行探讨,研究规制机构、企业和劳动者三方行为主体的博弈,通过分析存在的问题,提出解决职业健康规制的对策。在理顺职业健康规制体制,健全机构的同时不断完善法规体系。同时,加强对劳动者职业健康的保障,完善第三方介入机制,并且加大对违规企业的处罚力度,提高对劳动者的赔偿。不断强化企业作为职业健康责任主体的意识,推进职业危害防治技术创新,培养"以人为本"的职业健康安全文化观念。  相似文献   
58.
The present study was undertaken to determine the persistence and mobility of 2,4-dichlorophenoxy acetic acid (2,4-D) in unsaturated soil zone under real field conditions for the wheat crop in Roorkee, India. Three experimental plots were chosen in the agricultural field itself to represent the real field conditions in the study area and the potential movement and persistence of herbicide 2,4-D was investigated under three different irrigation treatments. The presence of herbicide along with soil water content was determined in soil at different depths at a temporal scale. The movement of the herbicide was also simulated numerically by solving the coupled soil water content movement and mass transport equations using HYDRUS-1D. The measured soil water content trends and the 2,4-D concentration profiles showed a good agreement with the numerically simulated results. The maximum effect of the herbicide was primarily retained up to 15 cm of the soil profile. The current existing dosage of 0.5 kg ha−1 of pesticide was found to be safe to avoid soil contamination as no residue of 2,4-D was traced at the end of the wheat crop season in any of the plots. Higher concentrations of 2,4-D were also simulated numerically and the simulated results showed that the safe dosage of pesticide application would depend on irrigation treatments.  相似文献   
59.
Thevenon F  Adatte T  Wildi W  Poté J 《Chemosphere》2012,86(5):468-476
This study investigates faecal indicator bacteria (FIB), multiple antibiotic resistant (MAR), and antibiotic resistance genes (ARGs), of sediment profiles from different parts of Lake Geneva (Switzerland) over the last decades. MARs consist to expose culturable Escherichia coli (EC) and Enterococcus (ENT) to mixed five antibiotics including Ampicillin, Tetracycline, Amoxicillin, Chloramphenicol and Erythromycin. Culture-independent is performed to assess the distribution of ARGs responsible for, β-lactams (blaTEM; Amoxicillin/Ampicillin), Streptomycin/Spectinomycin (aadA), Tetracycline (tet) Chloramphenicol (cmlA) and Vancomycin (van). Bacterial cultures reveal that in the sediments deposited following eutrophication of Lake Geneva in the 1970s, the percentage of MARs to five antibiotics varied from 0.12% to 4.6% and 0.016% to 11.6% of total culturable EC and ENT, respectively. In these organic-rich bacteria-contaminated sediments, the blaTEM resistant of FIB varied from 22% to 48% and 16% to 37% for EC and ENT respectively, whereas the positive PCR assays responsible for tested ARGs were observed for EC, ENT, and total DNA from all samples. The aadA resistance gene was amplified for all the sediment samples, including those not influenced by WWTP effluent water. Our results demonstrate that bacteria MARs and ARGs highly increased in the sediments contaminated with WWTP effluent following the cultural eutrophication of Lake Geneva. Hence, the human-induced changing limnological conditions highly enhanced the sediment microbial activity, and therein the spreading of antibiotic resistant bacteria and genes in this aquatic environment used to supply drinking water in a highly populated area. Furthermore, the presence of the antibiotic resistance gene aadA in all the studied samples points out a regional dissemination of this emerging contaminant in freshwater sediments since at least the late nineteenth century.  相似文献   
60.
A fungal perspective on conservation biology   总被引:1,自引:0,他引:1       下载免费PDF全文
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación  相似文献   
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