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61.
The aim of this paper is to identify the factors that drive support levels for wind on-shore electricity in the Member States of the European Union (EU) with the help of econometric techniques. The econometric analysis is based on cross-section linear regressions with ordinary least squares. Four alternative specifications of the model have been estimated. The estimates comply with the basic hypotheses of the lineal model, i.e., absence of multicollinearity, accurate functional form, homokedasticity and normality in the distribution of errors. Thus, the estimations are unbiased, efficient and consistent. The results show that countries with higher wind energy generation costs have higher support levels. The higher support levels in countries with higher carbon intensities suggest that wind energy deployment is regarded as effective to mitigate carbon emissions. The type of support scheme also influences support levels, with feed-in tariffs leading to lower levels of support than other instruments. In addition, a general good investment climate in the country makes higher support levels less necessary, stressing the importance of lowering risks in order to reduce support levels and, thus, financial transfers from consumers to producers. Thus, providing stable regulatory frameworks should be a priority of policy-makers. The rest of variables (renewable energy resource potentials, administrative barriers, energy import dependency, interest rates, share of wind energy in total electricity generation as a proxy of lobbying pressures and electricity demand) are not statistically significant in most specifications and some of them do not have the expected sign.  相似文献   
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A simple, sensitive and selective method by solvent extraction-first derivative spectrophotometry is described for the determination of microamounts of copper in water by means of its reaction and extraction at pH 8.0 with 3-(4-phenyl-2-pyridinyl-5-phenyl-1,2,4-triazine) (PPT) and picrate (2,4,6-trinitro-phenol) into 1,2-dichloroethane. Copper was thus determined in the range 7.5–350 ng/ml with a detection limits (3) of 2.3 ng/ml. The relative standard deviations were in all instances less than 2.0%. The proposed method was successfully applied for the determination of copper in several kinds of water.  相似文献   
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The Almería-Oran Oceanographic Front (AOOF) has been proposed as an effective marine barrier to gene flow between the NE Atlantic Ocean and the Mediterranean Sea for several species. Previous studies using allozymes and mitochondrial DNA have reported a scenario of secondary intergradation between populations of Mytilus galloprovincialis from those basins, with the allelic frequencies of some loci showing abrupt clinal patterns across the AOOF. In this study, we aimed at testing the congruence between six neutral polymorphic microsatellites versus previous data on allozymes and mtDNA-RFLPs, at depicting the population structure of this species in the Iberian Peninsula. Microsatellite genotyping was scored on 17 samples of mussels collected in the Iberian coast, including some areas not sampled before. Microsatellites exhibited larger intrabasin diversity (F SC = 1.72%, ), similar interbasin differentiation (F CT = 2.81%) and fewer allelic clines than allozymes or mtDNA haplotypes. These results fully support the scenario of secondary intergradation with some ongoing gene flow between basins, as proposed in previous analyses. Moreover, this congruence between markers and analyses separated by a 12-year period (1988–2000) confirm the temporal stability of this marine barrier at shaping the Iberian phylogeographic break in M. galloprovincialis. In addition, the genetic continuity between the NE Atlantic (Portugal) and the Alboran Sea seems to be warranted across the Gulf of Cadiz and the Gibraltar strait after the present microsatellite data. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
65.
Black-browed albatrosses (Thalassarche melanophris) disperse over the Argentinean Continental Shelf and neighboring waters during their non-breeding season. It is one of the most frequent seabirds attending fishing vessels and also the most common Procellariform in the bycatch of longliners and trawlers in the area. Understanding the use of fishery discards by this species is an important issue when assessing the potential effect of strategic discard management in decreasing the abundance, interactions, and mitigating mortality. In the present study, we analyzed carbon and nitrogen stable isotope compositions in the blood of Black-browed albatrosses to assess the relative contribution of discards from different fisheries to the diet of this species in winter. Samples were obtained in winter 2011 from fishing vessels operating between 41–43°S and 57–59°W. No sex differences in δ13C and δ15N were observed. Results indicate that during their non-breeding season, isotopic signatures of Black-browed albatrosses are closer to discards and offal generated by fisheries and in particular by trawlers. The large fishing effort of trawl fisheries in Argentina highlights the urgency of an exhaustive analysis to find practical and effective ways to reduce the number of seabirds attending trawlers.  相似文献   
66.
The human health impact of the historic and current mining and industrial activities in Tunisia is not known. This study assessed the exposure to metals in the population of Southern Tunisia, using biomonitoring. The aim of this pilot study was to evaluate metal exposure on 350 participants living near mining and active industrial areas in the South of Tunisia. Blood specimens were analyzed for metals (Cd, Cr, As, and Ni) by Atomic Absorption Spectrometer equipped with Zeeman background correction and AS-800 auto sampler by graphite furnace and graphite tubes with integrated L'vov platform. The sample population was classified according to different age groups, sex, smoking habit, sea food and water drinking consumption, occupational exposure, amalgam fillings and place of residence. The blood As, Cd, Cr and Ni values expressed as mean?±?SD were 1.56?±?2.49, 0.74?±?1.15, 35.04?±?26.02 and 30.56?±?29.96 μg/l, respectively. Blood Cd and Ni levels in smokers were 2 and 1.2 times, respectively, higher than in non-smokers. Blood Cd levels increase significantly with age (p?=?0.002). As, Cd and Ni were significantly correlated with gender and age (p?<?0.05). Cd level in blood samples of subjects occupationally exposed was 1.3 times higher than that of non-exposed. Blood metals were not significantly affected by amalgam fillings, place of living and sea food and drinking water consumption. This first biomonitoring study of metal exposure in the South of Tunisia reveals a substantial exposure to several metals. The pathways of exposure and health significance of these findings need to be further investigated.  相似文献   
67.
Effective ecosystem‐based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components’ vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions.  相似文献   
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Our aim was to explore the adaptation choices to climate change in the grapevine regions of Spain from two points of view. First, what are the main reasons for concern? Second, how large is the adaptation effort in each region? We address the first question by measuring sensitivity to climate change with Huglin, Cold Night and Dryness Indices over the entire territory, providing information on the adaptation type (e.g. varieties, zoning, water allocation). We then estimate probabilistic projections across scenario, zone and sensitivity indices in the 56 Protected Designation of Origin areas to inform on the magnitude of the adaptation effort. Second, we propose an adaptation effort measure that is framed according to the local environmental context. Results suggest that most areas urgently need an adaptation plan due to the deterioration of production and quality indices as a result of climate change. Potential opportunities in many climate regions might be limited by current policy. The production objectives of quality and quantity trade-offs will probably need to be revised by analysing the sustainability of grapevine production.  相似文献   
70.
Mitigation and Adaptation Strategies for Global Change - Soils hold the largest pool of organic carbon (C) on Earth; yet, soil organic carbon (SOC) reservoirs are not well represented in climate...  相似文献   
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