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831.
洪水灾害间接经济损失评估研究进展 总被引:3,自引:0,他引:3
受全球气候变化及人类活动的影响,洪水灾害发生的频率和损失越来越大,洪灾直接经济损失评估研究不断深入,但是,洪灾间接经济损失评估研究相对薄弱。为了能综合地对洪水灾害间接经济损失进行科学的评价,回顾了国内外洪水灾害间接经济损失评估的研究现状,综述了洪水灾害间接经济损失的内涵及组成(减产停产损失、产业关联损失和投资溢价损失),分析了他们之间的关系及相应的评估方法特点。指出洪水灾害间接经济损失主要指产业关联损失,投入产出法是间接经济损失评估的适用方法,但该方法的使用必须作适应性改进,上述观点可供洪灾间接经济损失评价参考。 相似文献
832.
833.
考察了阴极负载Co3O4和MnOOH对天然水体中沉积物微生物燃料电池(SMFC)产电性能和SMFC对沉积物中有机质去除率的影响。实验结果表明,SMFC阴极负载Co3O4和MnOOH后,体系的输出电压由483 mV增大到549 mV和534 mV;相应体系的内阻由206 Ω显著降低到99 Ω和128 Ω,最大功率密度(Pmax)由3.3 mW/m2增大到9.1 mW/m2和6.6 mW/m2。此外,SMFC体系的电流密度与沉积物中烧失量(LOI)、易氧化有机质(ROOM)去除率呈线性关系,并且阴极负载Co3O4和MnOOH可以促进阳极沉积物中有机质的去除。 相似文献
834.
通过标准GM 9540P和GMW 14872两种方法的试验,评价了不锈钢SUH409L、B409和409DG的耐蚀性,两种方法的结果表明三种不锈钢的耐蚀性能由强至弱依次为SUH409L〉B409〉409DG。 相似文献
835.
Sari Kontunen-Soppela Juha Parviainen Mikael Brosché Ramesh C. Thakur Jaakko Kangasjärvi David F. Karnosky 《Environmental pollution (Barking, Essex : 1987)》2010,158(4):959-968
Gene expression responses of paper birch (Betula papyrifera) leaves to elevated concentrations of CO2 and O3 were studied with microarray analyses from three time points during the summer of 2004 at Aspen FACE. Microarray data were analyzed with clustering techniques, self-organizing maps, K-means clustering and Sammon's mappings, to detect similar gene expression patterns within sampling times and treatments. Most of the alterations in gene expression were caused by O3, alone or in combination with CO2. O3 induced defensive reactions to oxidative stress and earlier leaf senescence, seen as decreased expression of photosynthesis- and carbon fixation-related genes, and increased expression of senescence-associated genes. The effects of elevated CO2 reflected surplus of carbon that was directed to synthesis of secondary compounds. The combined CO2 + O3 treatment resulted in differential gene expression than with individual gas treatments or in changes similar to O3 treatment, indicating that CO2 cannot totally alleviate the harmful effects of O3. 相似文献
836.
The role of radial oxygen loss and root anatomy on zinc uptake and tolerance in mangrove seedlings 总被引:1,自引:0,他引:1
H. Cheng N.F.Y. Tam S.Y. Li Z.H. Ye 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1189-1196
Root anatomy, radial oxygen loss (ROL) and zinc (Zn) uptake and tolerance in mangrove plants were investigated using seedlings of Aegiceras corniculatum, Bruguiera gymnorrhiza and Rhizophora stylosa. The results revealed that B. gymnorrhiza, which possessed the ‘tightest barrier’ in ROL spatial patterns among the three species studied, took up the least Zn and showed the highest Zn tolerance. Furthermore, zinc significantly decreased the ROL of all three plants by inhibition of root permeability, which included an obvious thickening of outer cortex and significant increases of lignification in cell walls. The results of SEM X-ray microanalysis further confirmed that such an inducible, low permeability of roots was likely an adaptive strategy to metal stress by direct prevention of excessive Zn entering into the root. The present study proposes new evidence of structural adaptive strategy on metal tolerance by mangrove seedlings. 相似文献
837.
838.
In this study, different concentrations of five food dyes (amaranth, patent blue, carminic acid, indigotine and erythrosine) have been evaluated for genotoxicity in the Somatic Mutation and Recombination Test (SMART) of Drosophila melanogaster. Standard cross was used in the experiment. Larvae including two linked recessive wing hair mutations were chronically fed at different concentrations of the test compounds in standard Drosophila Instant Medium. Feeding ended with pupation of the surviving larvae. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can result from either somatic mutation or somatic recombination. For the evaluation of genotoxic effects, the frequencies of spots per wing in the treated series were compared to the control group, which was distilled water. The present study shows that carminic acid and indigotine demonstrated negative results while erythrosine demonstrated inconclusive results. In addition 25 mg mL−1 concentration of patent blue and 12.5, 25 and 50 mg mL−1 concentrations of amaranth demonstrated positive results in the SMART. 相似文献
839.
The Taoer River basin is the epitome in the west of Northeast China and it is one of the most fragile and sensitive ecoregions. Thus, protection of water quality of the Taoer River is important. Not only point source pollution but non-point source (NPS) pollution results in deteriorating water quality. In this study, long-term hydrologic impact assessment model was used to evaluate the impacts of land use change impacts on NPS pollution, and the replacement cost method was used to calculate the economic loss caused by NPS pollution. Through analyzing the NPS pollutant loads of different land categories and the economic loss, the article puts forward that there exists a close relationship between land-use types and NPS pollution, and agricultural pollution is the main component of the NPS pollution in this area. The results of this study can provide decision-making basis for agricultural development and land-use change. 相似文献
840.
环境问题备受关注,环境污染严重影响中国经济的增长质量.本文采用治理成本法测算了1989 -2008年中国环境污染造成的经济损失,利用环境污染经济损失数据,采用协整理论研究了中国环境污染损失与经济增长之间的关系.研究表明,我国经济总量与环境污染之间存在长期均衡关系,经济增长是造成环境污染的基础性原因,并且环境污染状况随经济增长仍有扩大的趋势,至今尚未出现环境库兹涅茨曲线拐点的迹象.然后,本文从产业结构、能源结构和效率角度揭示了环境污染的结构性成因.研究认为,高污染行业在整个国民经济中比重过大是造成环境污染的产业结构方面的成因;以煤炭为主的能源消费和高耗能产品增长过快是造成环境污染的能源结构成因;能源效率低下是造成环境污染的技术性成因;资源能源价格长期偏低和法律法规滞后是造成环境污染的制度性缺陷.最后,针对问题提出,只有切实转变经济增长方式,突出技术创新、健全市场机制、完善环境法规才是解决环境污染问题的根本出路. 相似文献