3 resultados para 616.865

em Portal de Revistas Científicas Complutenses - Espanha


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In this study, Evernia prunastri, a lichen growing in its natural habitat in Morocco was analysed for the concentration of five heavy metals (Fe, Pb, Zn, Cu and Cr) from eleven sites between Kenitra and Mohammedia cities. The control site was Dar Essalam, an isolated area with low traffic density and dense vegetation. In the investigated areas, the concentration of heavy metals was correlated with vehicular traffic, industrial activity and urbanization. The total metal concentration was highest in Sidi Yahya, followed by Mohammedia and Bouznika. The coefficient of variation was higher for Pb and lower for Cu, Zn and Fe. The concentrations of most heavy metals in the thalli differed significantly between sites (p<0.01). Principal component analysis (PCA) revealed a significant correlation between heavy metal accumulation and atmospheric purity index. This study demonstrated also that the factors most strongly affecting the lichen flora were traffic density, the petroleum industry and paper factories in these areas. Overall, these results suggest that the index of atmospheric purity and assessment of heavy metals in lichen thalli are good indicators of the air quality at the studied sites.

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The new class, the Tamaricetea arceuthoidis, is described covering riparian and intermittent shrubby vegetation of the Irano-Turanian Region in the southwestern and Central Asia and the Lower Volga valley. The dominating species are species of the genus Tamarix that refer high water table in arid and semi-arid habitats with high to moderate salinity. This new class is an ecological analogon of the Nerio-Tamaricetea occurring in the Mediterranean Basin.

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This article fi rst summarizes the structural reforms of pensions (total or partial privatization) in Latin America and Central and Eastern Europe, identifying their advantages and disadvantages, and does the same with the international process of re-reforms of pensions with a greater role of the state. Second, chooses Chile as a case study, as a world pioneer in both types of reforms; describes their characteristics and effects on social welfare of the structural reform of 1981 and the re-reform of 2008. Such effects are evaluated based on ten basic principles of social security from the International Labour Offi ce (ILO): 1) social dialogue to approve the reforms, 2) universal coverage of the population, 3) equal treatment of insured persons, 4) social solidarity, 5) gender equity, 6) suffi ciency of benefi ts, 7) effi ciency and reasonable administrative cost, 8) social participation in the management of the system, 9) role of the state and supervision, and 10) fi nancial sustainability. Third, it summarizes the advantages and disadvantages-challenges of the re-reform and informs on the current debate for further reforms.