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381.
J. M. Rodriguez-Anton L. Rubio-Andrada M. S. Celemín-Pedroche M. D. M. Alonso-Almeida 《国际发展与全球生态学杂志》2013,20(8):708-720
ABSTRACTSince the United Nations approved the eight Millennium Development Goals in 2000 and, 15 years later, the 2030 Agenda for Sustainable Development and its 17 Sustainable Development Goals (SDGs), the highest political institutions in the world have not stopped worrying about achieving the sustainability of the planet. Also in 2015, the European Commission prepared the European Union Action Plan for the Circular Economy, seeking a transition towards a less linear economy, in which products, materials, and resources are kept in the system for as long as possible and in which the generation of waste is minimized.Since then, the European Union has continued issuing reports and communications to accelerate this process in search of a circular economy, making continuous references to the fact that, through circular economy initiatives, the SDGs would be fulfilled. In this context, the objectives of this paper are 1) to determine, through exploratory factor analysis and correlation analysis, whether there is a statistically significant relationship between circular economy initiatives undertaken in the EU and compliance with the SDGs; 2) to check, through a cluster analysis, if there are homogeneous groups of countries worldwide in terms of compliance with the SDGs; and 3) using this same technique, to check whether the countries that make up the EU achieve similar results in terms of compliance with the SDGs. 相似文献
382.
Joern Birkmann 《Environmental Hazards》2013,12(1):20-31
This paper outlines selected approaches to measuring risk and vulnerability to hazards of natural origin using indicators and indices. It discusses their applicability, usefulness and policy implications. Indicators and indices have been developed on different scales and for different purposes. The paper will briefly introduce three global approaches to disaster-risk identification and will juxtapose them with one local approach in order to examine the differences concerning the functions and the purpose of the assessment as well as their impact for policy development. In contrast to an earlier comparative analysis of the three global disaster-risk indicator programmes by Mark Pelling in 2004, which focused primarily on the methodologies used, this paper places more emphasis on aspects of applicability and policy implications and outlines challenges and limitations of the different approaches. Since the assessment and mapping of human vulnerability is less developed than hazard assessment work [Pelling M., 2004. Visions of Risk: A Review of International Indicators of Disaster Risk and its Management. UNDP—Bureau for Crisis Prevention and Recovery (BRCP), Geneva], this paper focuses in greater depth on how the approaches capture vulnerability. Conclusions will be formulated on how to further enhance vulnerability identification, particularly at the sub-national level. 相似文献
383.
再生水紫外线-氯联合消毒工艺特性研究 总被引:2,自引:0,他引:2
以二级出水作为消毒对象,比较了紫外线-氯联合消毒与单一紫外线消毒对水中肠道指示菌的灭活效果,考察了联合消毒工艺副产物(三卤甲烷)生成情况.结果表明,单一紫外线消毒对肠道指示菌的灭活曲线在剂量大于10mJ/cm2时存在拖尾现象,剂量为80mJ/cm2时对总大肠菌群最高对数灭活率约为2.5;而在紫外线剂量20mJ/cm2、氯投加量8mg/L(接触时间30min)条件下,紫外线-氯联合消毒对总大肠菌群的对数灭活率达到7.0.20mJ/cm2紫外线与8mg/L氯消毒组合及80mJ/cm2紫外线与3mg/L氯消毒组合均可有效灭活总大肠菌群浓度至3CFU/L以下.经紫外线照射后再氯消毒,二级出水中三卤甲烷生成量仅为10~55mg/L.80mJ/cm2紫外线照射再氯消毒后三卤甲烷生成量略高于20mJ/cm2紫外线照射再氯消毒的情形.紫外线消毒后投加氯消毒,可有效提高再生水消毒效果,控制消毒副产物生成量. 相似文献
384.
Jing HUO Ye YU Ling GE Bo ZHANG Yiliang HE 《Frontiers of Environmental Science & Engineering》2015,9(2):197
C60, as one of carbon nanomaterials widely used in various fields, could be released into the water environment thus exerting some potential health risks to human beings. This work examined the behavior of aqueous stable colloidal nano-C60 (nC60) aggregates under different environmental conditions including Polyethylene glycol octylphenol ether (TX100) micelles concentration, pH, and reaction time when exposed to TX100 micelles. Results show that the nC60 aggregates became more dispersive and restored the capability of generating the singlet oxygen when exposed to TX100 micelles. With the increase of TX100 concentration, smaller average size of nC60 aggregates was observed in dynamic light scattering (DLS) analysis, the fluorescence intensity of TX100 was more quenched by nC60 aggregates, and the kinetic rate constant of generating the singlet oxygen for nC60 aggregates was improved. The mean size of nC60 aggregates in the presence of TX100 had no obvious variations when the pH ranged from 4 to 8. The longer reaction time between nC60 aggregates and TX100 led to a higher kinetic rate constant of generating the singlet oxygen. Collective data suggest that variations in physicochemical properties of nC60 aggregates are strongly dependent on the surrounding media under different environmental conditions and directly govern nC60’s transport behavior and potential toxicity. 相似文献
385.
甲醛(HCHO)是大气光化学重要污染物之一,为研究西南地区郊区大气夏季甲醛污染特征选取了四川省成都市新津区进行大气甲醛观测,结合NOx、O3、PAN、J-value、温湿度、风速风向、天气数据进行分析.观测期间成都市新津区夏季甲醛浓度为0.76×10-9~12.50×10-9(V/V),均值为3.47×10-9±2.05×10-9(V/V),呈现明显的日变化规律.结合数据分析可知,一次人为排放源在成都郊区夏季日间甲醛贡献中占比较低.观测期间甲醛受光照的影响较大,与O3、PAN、J-value普遍呈现一致的变化规律,因此成都市夏季日间甲醛主要来源为甲醛前体物的二次光化学反应. 相似文献
386.
Traditional bacterial indicators used in public health to assess water quality and the Biolog system were evaluated to compare their response to biological, chemical, and physical habitat indicators of stream condition both within the state of Oregon and among ecoregion aggregates (Coast Range, Willamette Valley, Cascades, and eastern Oregon). Forty-three randomly selected Oregon river sites were sampled during the summer in 1997 and 1998. The public health indicators included heterotrophic plate counts (HPC), total coliforms (TC), fecal coliforms (FC) and Escherichia coli (EC). Statewide, HPC correlated strongly with physical habitat (elevation, riparian complexity, % canopy presence, and indices of agriculture, pavement, road, pasture, and total disturbance) and chemistry (pH, dissolved O2, specific conductance, acid-neutralizing capacity, dissolved organic carbon, total N, total P, SiO2, and SO4). FC and EC were significantly correlated generally with the river chemistry indicators. TC bacteria significantly correlated with riparian complexity, road disturbance, dissolved O2, and SiO2 and FC. Analyzing the sites by ecoregion, eastern Oregon was characterized by high HPC, FC, EC, nutrient loads, and indices of human disturbance, whereas the Cascades ecoregion had correspondingly low counts of these indicators. The Coast Range and Willamette Valley presented inconsistent indicator patterns that are more difficult to characterize. Attempts to distinguish between ecoregions with the Biolog system were not successful, nor did a statistical pattern emerge between the first five principle components and the other environmental indicators. Our research suggests that some traditional public health microbial indicators may be useful in measuring the environmental condition of lotic systems. 相似文献
387.
Klemas VV 《Environmental management》2001,27(1):47-57
Advances in technology and decreases in cost are making remote sensing (RS) and geographic information systems (GIS) practical and attractive for use in coastal resource management. They are also allowing researchers and managers to take a broader view of ecological patterns and processes. Landscape-level environmental indicators that can be detected by Landsat Thematic Mapper (TM) and other remote sensors are available to provide quantitative estimates of coastal and estuarine habitat conditions and trends. Such indicators include watershed land cover, riparian buffers, shoreline and wetland changes, among others. With the launch of Landsat 7, the cost of TM imagery has dropped by nearly a factor of 10, decreasing the cost of monitoring large coastal areas and estuaries. New satellites, carrying sensors with much finer spatial (1-5 m) and spectral (200 narrow bands) resolutions are being launched, providing a capability to more accurately detect changes in coastal habitat and wetland health. Advances in the application of GIS help incorporate ancillary data layers to improve the accuracy of satellite land-cover classification. When these techniques for generating, organizing, storing, and analyzing spatial information are combined with mathematical models, coastal planners and managers have a means for assessing the impacts of alternative management practices. 相似文献
388.
Susan Fuertsch Fanok Ellen E. Wohl 《Journal of the American Water Resources Association》1997,33(5):1091-1102
ABSTRACT: Gaging stations established in 1895 at Millville, West Virginia and in 1882 at Harpers Ferry, West Virginia record flows ranging from a maximum of 6,509 m3s-1 to a minimum of 2 m3s-1. Historical and botanical indicators were used to extend the systematic flood record of the Shenandoah River for a study reach approximately 7.5-km long. The long systematic record at the site provides a good opportunity to assess the accuracy of these sources of paleoflood information. Habitation of the area by settlers of European descent began in 1733, and historical flood records extend from 1748. Qualitative historical records from different sources were compared to yield the most complete flood history. The correlation between the various sources was extremely high. Botanical flood evidence preserved as adventitious sprouts, tree scars, and ring anomalies were documented in 37 trees. A flood chronology established from these data extended from 1896 to 1955. Botanical indicators provided an accurate, although incomplete, flood chronology. The ability to determine accurate flood stages from paleohydrologic indicators varied. Historical data yielded relatively accurate stages to within 1–2 m; only minimum values of flood stage could be obtained from botanical indicators. These results illustrate some of the strengths and weaknesses of paleohydrologic investigations in the eastern United States. 相似文献
389.
Environmental evaluation of subdivision site developments 总被引:5,自引:0,他引:5
An environmental evaluation was performed at 16 subdivision sites within four communities in east-central Michigan. The primary
objective was to evaluate the fit between environmental ordinances and the physical/environmental conditions to which they
were applied. An environmental response index was developed with indicators to assess water, soil, slope, development density,
roads, vegetation, and ecology. Water-related indicators achieved the highest scores, while soil-related indicators scored
the poorest, with generally poor performance across all indicators. The poor performance indicates there are problems in the
ability of environmental ordinances developed at broader jurisdictional scales (e.g., the state) to address the existing environmental
conditions at smaller geographic scales (subdivisions within communities). Two key problems include the lack of scientific
specificity in the broader state-level ordinances and the lack of local expertise and/or resources to monitor the environment. 相似文献
390.
David Seckler R. K. Sampath S. K. Raheja 《Journal of the American Water Resources Association》1988,24(4):855-860
ABSTRACT: This paper presents a statistically valid index for measuring the performance of irrigation systems. The index is applied to a sample of 39 farms on a watercourse under the warabandi system of irrigation management in India. It is found that while the farmers in fact irrigated almost exactly the total amount of irrigated area as designed, inter-farm variations were considerable. The index shows that the degree of error of managerial effectiveness of irrigation on this watercourse is 20 percent. Therefore it is concluded that the system is performing at 80 percent effectiveness. 相似文献