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201.
Climate change is one of the major worldwide environmental concerns. It is especially the case in many developed countries, where the greenhouse gas emissions responsible for this change are mainly concentrated. For the first time, the Kyoto Protocol includes an international agreement for the reduction of the net emissions of these gases. To fulfil this agreement measures designed to reduce or limit current emissions have to be brought into force. Consequently, fears have arisen about possible consequences on competitiveness and future development of manufacturing activities and the need for support mechanisms for the affected sectors is obvious. In this paper, we carry out a study of the emissions of gases responsible for climate change in Asturias (Spain), a region with an important economic presence of sectors with intensive emissions of CO(2), the chief greenhouse gas. To be precise, in the first place, the volumes of direct emissions of the said gases in 1995 were calculated, showing that the sectors most affected by the Kyoto Protocol in Asturias are iron and steel and electricity production. Secondly, input-output analysis was applied to determine the direct and indirect emissions and the direct, indirect and induced emissions of the different production sectors, respectively. The results derived from the direct and indirect emissions analysis and their comparison with the results of the former allow us to reach some conclusions and environmental policy implications.  相似文献   
202.
Methyl-mercury (CH3Hg+) production was studied in freshwaters from lake Moreno, an ultraoligotrophic system belonging to Northern Patagonia. Hg2+ labelled with high specific activity 197Hg was spiked to water samples in concentrations of 10 ng l(-1), and incubated in laboratory for 3d time trends under different conditions. Experimental water was sampled daily to evaluate CH3(197)Hg+ production. Lake water used in the experiments was sampled just below the upper limit of the metalimnion ( approximately 30 m depth), where maximum values of chlorophyll a have been measured previously. Sampling was performed in late autumn, when the plankton fraction <50 microm exhibited mercury concentrations up to 260 microg g(-1) dry weight. The experiments analysed lake water filtered through 50, 20, and 0.2 microm (filter-sterilized) mesh nets. ASTM grade 1 water was also incubated for control. All the experiments were run in an environmental chamber under controlled temperature and light regime. High Hg2+ conversion to CH3Hg+, up to 50%, was measured in lake water, in a process stimulated by light. CH3Hg+ production was two-fold higher after 3d of incubation with illumination compared to total darkness. Sterile lake water showed conversions up to 30%, while the planktonic components seem to enhance the CH3Hg+ production. Overall, our results provide evidence that lake Moreno waters favour CH3Hg+ production in processes stimulated by light. Although biotic components certainly contribute to enhance mercury methylation, water chemistry plays a key role in this process. We hypothesize that dissolved organic matter, particularly its quality, could be decisive.  相似文献   
203.
This study was performed to determine sublethal responses of two invertebrate species by using field deployments in areas affected by oil spills, which are acute in the Galician Coast (NNW, Spain) and chronic in the Bay of Algeciras (SSW, Spain). The organisms employed were the crab Carcinus maenas and the clam Ruditapes philippinarum, and during 28 days the animals were exposed to contaminated sediments in cages under field conditions. Different biomarkers of exposure were determined after a 28-day period exposure: ethoxyresorufin O-deethylase (EROD), phase I detoxification enzyme, glutathione-S-transferase (GST) phase II detoxification enzyme but also implicated in oxidative stress events, glutathione peroxidase (GPX) and glutathione reductase (GR), both antioxidant enzymes. In addition, histopathological effects in target tissues of the deployed organisms were evaluated. Biomarker measurements were linked with the concentration of chemicals in the sediments in order to elucidate the type, source and bioavailability of contaminants that produce adverse effects in the bioindicator species. Results obtained in this study have shown how the application of the selected battery of biomarkers under field bioassays allows for the identification of alternative sources of stress that are not observable in laboratory experiments.  相似文献   
204.
The aim of this study was to measure of serum levels of p,p′-dichlorodiphenyl trichloroethane (p,p′-DDT), p,p′-dichlorodiphenyl dichlorethylene (p,p′-DDE), β-hexachlorocyclohexane (β-HCH), and hexachlorobenzene (HCB) in healthy adults in Spain. Furthermore, we also analyzed these levels according to dietary, other lifestyle factors and anthropometric characteristics. We measured the concentrations of such organochlorine pesticides (OCPs) in serum samples collected during 1992–1996 from 953 subjects aged 35–64 years, they were residents of five Spanish regions, they were randomly selected from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. OCPs were determined by means of gas chromatography with electron-capture detection (GC-ECD). The most frequent compound found in serum was p,p′-DDE, present in 98% of the samples, followed by HCB and β-HCH, found in 89% and 77% of samples, respectively, while p,p′-DDT could be measured only in 26% of subjects. The geometric means of serum concentrations (ng/g lipid) were 822 for p,p′-DDE, 167 for β-HCH, and 379 for HCB. The concentrations of all OCPs were positively associated with age and body mass index, and decreased along the period of blood collection. No association was found between OCPs levels and dietary factors. The concentrations of p,p′-DDE and β-HCB were higher in Murcia, one of southern regions, most likely associated with intensive past use of pesticides related to agricultural practices, while higher levels of HCB were found in Navarra, located in the north, maybe due to industrial use rather than agricultural application.  相似文献   
205.
This is the first test of a highly charged swelling mica's (Na-2-mica) ability to reduce the plant-absorbed Cu in Cu-contaminated soils from Chile. Perennial ryegrass (Lolium perenne L.) was grown in two acid soils (Sector 2: pH 4.2, total Cu = 172 mg Cu kg−1 and Sector 3: pH 4.2, total Cu = 112 mg Cu kg−1) amended with 0.5% and 1% (w/w) mica, and 1% (w/w) montmorillonite. At 10 weeks of growth, both mica treatments decreased the shoot Cu of ryegrass grown in Sector 2 producing shoot Cu concentrations above 21-22 mg Cu kg−1 (the phytotoxicity threshold for that species), yet the mica treatments did not reduce shoot Cu concentrations when grown in Sector 3, which were at a typical level. The mica treatments improved shoot growth in Sector 3 by reducing free and extractable Cu to low enough levels where other nutrients could compete for plant absorption and translocation. In addition, the mica treatments improved root growth in both soils, and the 1% mica treatment reduced root Cu in both soils. This swelling mica warrants further testing of its ability to assist re-vegetation and reduce Cu bioavailability in Cu-contaminated surface soils.  相似文献   
206.
Environmental Science and Pollution Research - The effectiveness of compost, peat-calcite, and wood ash to remove Ni from a circum-neutral-contaminated mine water was tested in continuous flow...  相似文献   
207.
Social capital is considered important for resilience across social levels, including communities, yet insights are scattered across disciplines. This meta-synthesis of 187 studies examines conceptual and empirical understandings of how social capital relates to resilience, identifying implications for community resilience and climate change practice. Different conceptualisations are highlighted, yet also limited focus on underlying dimensions of social capital and proactive types of resilience for engaging with the complex climate change challenge. Empirical insights show that structural and socio-cultural aspects of social capital, multiple other factors and formal actors are all important for shaping the role of social capital for guiding resilience outcomes. Thus, finding ways to work with these different elements is important. Greater attention on how and why outcomes emerge, interactions between factors, approaches of formal actors and different socio-cultural dimensions will advance understandings about how to nurture social capital for resilience in the context of climate change.  相似文献   
208.

Background, aim, and scope

Ten years of public health interventions on industrial emissions to clean air were monitored for the Mediterranean city of Cartagena. During the 1960s, a number of large chemical and non-ferrous metallurgical factories were established that significantly deteriorated the city’s air quality. By the 1970s, the average annual air concentration of sulfur dioxide (SO2) ranged from 200 to 300 µg/m3 (standard conditions units). In 1979, the Spanish government implemented an industrial intervention plan to improve the performance of factories and industrial air pollution surveillance. Unplanned urban development led to residential housing being located adjacent to three major factories. Factory A produced lead, factory B processed zinc from ore concentrates, and factory C produced sulfuric acid and phosphates. This, in combination with the particular abrupt topography and frequent atmospheric thermal inversions, resulted in the worsening of air quality and heightening concern for public health. In 1990, the City Council authorized the immediate intervention at these factories to reduce or shut down production if ambient levels of SO2 or total suspended particles (TSP) exceeded a time-emission threshold in pre-established meteorological contexts. The aim of this research was to assess the appropriateness and effectiveness of the intervention plan implemented from 1992 to 2001 to abate industrial air pollution.

Materials and methods

The maximum daily 1-h ambient air level of SO2, NO2, and TSP pollutants was selected from one of the three urban automatic stations, designed to monitor ambient air quality around industrial emissions sources. The day on which an intervention took place to reduce and/or interrupt industrial production by factory and pollutant was defined as a control day, and the day after an intervention as a post-control day. To assess the short-term intervention effect on air quality, an ecological time series design was applied, using regression analysis in generalized additive models, focusing on day-to-day variations of ambient air pollutants levels. Two indicators were estimated: (a) appropriateness, the ratio between mean levels of the pollutant for control days versus the other days, and (b) effectiveness, the ratio between mean levels of the pollutant for post-control days versus the other days. Ratios in regression analyses were adjusted for trend, seasonality, temperature, humidity and atmospheric pressure, calendar day, and special events as well as the other pollutants.

Results

A total of 702 control days were made on the factories’ industrial production during the 10-year period. Fifteen reductions and five shutdown control days took place at factory A for ambient air SO2. At factory B, more controls were carried out for the SO2 pollutant in the years 1992–1993 and 1997. At factory C, the control days for SO2 decreased from 59 reductions and 14 shutdowns to a minimum from 1995 onwards, whereas the controls on TSP were more frequent, reaching a maximum of 99 reductions and 47 shutdowns in the last year. SO2 ambient air mean levels ranged from 456 to 699 µg/m3 among factories on reduction control days and between 624 and 1,010 µg/m3 on shutdown days. The TSP ambient air mean levels were 428 and 506 µg/m3 on reduction and shutdown days, respectively. For all types of control days and factories, a mean ratio of 104% (95% confidence interval [CI] 88 to 121) in SO2 levels was obtained and a mean ratio of 67% (95% CI 59 to 75) in TSP levels. Post-control days at all factories showed a mean ratio of ?16% (95% CI ?7 to ?24) in SO2 levels and a mean ratio of ?13% (95% CI ?7 to ?19) in TSP levels.

Discussion

Interventions on industrial production based on the urban SO2 and TSP ambient air levels were justified by the high concentrations detected. The best assessment of the interventions’ effectiveness would have been to utilize the ambient air pollutant concentration readings from the entire time of the production shutdowns or reductions; however, the daily hourly maximum turned out to be a useful indicator because of meteorological factors influencing the diurnal concentration profile. A substantial number of interventions were carried out from 1 to 3 am, when vehicular traffic was minimum. On the other hand, atmospheric stability undergoes diurnal cycling in the autumn–winter period due to thermal inversion, which reaches maximum levels around daybreak. Therefore, this increases the ambient air levels and justified the interventions carried out at daybreak in spite of the traffic influence.

Conclusions

All the interventions for SO2 and TSP were carried out when the measured ambient air levels of pollutants were exceeded, which shows the appropriateness of the intervention program. This excess was greater when intervening on SO2 than on the TSP levels. For both ambient air levels of SO2 and TSP, significant drops in air pollution were achieved from all three factories following activity reductions. The production shutdown controls were very effective, because they returned excess levels, higher than in the reduction controls, to everyday mean values.

Recommendations and perspectives

The Cartagena City observational system of intermittent control has proven to effectively reduce industrial emissions’ impact on ambient air quality. This experienced model approach could serve well in highly polluted industrial settings. From a public health perspective, studies are needed to assess that the industrial interventions to control air pollution were related to healthier human populations. Legislation was needed to allow the public administration to take direct actions upon the polluting industries.  相似文献   
209.

Background, aim and scope  

Marine and coastal sediments can accumulate substantial concentrations of metals and hydrocarbons, yet the consequences of this contamination for exposed biota in situ can be difficult to establish. Here, we examine the hypothesis that exposure to contaminated sediments can lead to detrimental effects in sediment-dwelling species. The combination of chemical and biological assessment allows the identification of the impact of chemical contamination, and their use as assessment tools is becoming increasingly important.  相似文献   
210.
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