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171.
This study aimed to assess the influence of excess iron on the capacity of accumulation of this heavy metal, mineral composition, and growth of Setaria parviflora and Paspalum urvillei. Seedlings were submitted to 0.009; 1; 2; 4; and 7 mM of Fe-EDTA. In both species there was an increase in the concentration of Fe, Zn, P, and Ca and a decrease in Mn, K, and Mg in the iron plaque. Both species accumulated more iron in roots. In the shoots, S. parviflora showed higher iron content, except at 7 mM. Iron altered the contents of Fe, Cu, K, and Mg in roots, and of Fe, Mn, Zn, N, P, K, Ca, and Mg in shoots. The two species tolerated high iron concentrations and accumulated high content of this element in both shoots and roots. The iron did not reduce their growth. Both species are indicated for studies aiming restoration of iron-contaminated areas.  相似文献   
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The Urban Cleaning Company of the City of Rio de Janeiro - COMLURB launched the Recycling Separation Center Project (Projeto Central de Separação de Recicláveis or CSR) in 2003. The objectives of the project were the adequate disposal of solid urban waste as well as the generation of employment and income. The COMLURB Project had economic, environmental and social facets, and the researchers sought to establish whether COMLURB had prepared reports that would enable evaluation of the investment made and the results obtained. In particular, the researchers sought to establish whether COMLURB financial statements set out the results of actions inherent to the CSR. We concluded from our analysis of the Project that the three elements of sustainability (social, environmental and economic), despite being fully present, were not adequately demonstrated. This study therefore proposes a model report with a view to enabling various information users to evaluate the results of the CSR Project.  相似文献   
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We report a small hawk-like diurnal bird from the early Oligocene (30–31 million years ago) of Poland. Aviraptor longicrus, n. gen. et sp. is of a size comparable with the smallest extant Accipitridae. The new species is characterized by very long legs, which, together with the small size, suggest an avivorous (bird-eating) feeding behavior. Overall, the new species resembles extant sparrowhawks (Accipiter spp.) in the length proportions of the major limb bones, even though some features indicate that it convergently acquired an Accipiter-like morphology. Most specialized avivores amongst extant accipitrids belong to the taxon Accipiter and predominantly predate small forest passerines; the smallest Accipiter species also hunts hummingbirds. Occurrence of a possibly avivorous raptor in the early Oligocene of Europe is particularly notable because A. longicrus coexisted with the earliest Northern Hemispheric passerines and modern-type hummingbirds. We therefore hypothesize that the diversification of these birds towards the early Oligocene may have triggered the evolution of small-sized avivorous raptors, and the new fossil may exemplify one of the earliest examples of avian predator/prey coevolution.

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As part of the monitoring program from Instituto Hidrográfico, since 1981 sediment and water samples have been collected from four different estuarine areas located along the continental coast of Portugal. The concentrations of different parameters were measured in the water and sediment samples. After normalization, the concentrations of chromium, mercury, lead and zinc in the sediments from the different areas were compared.  相似文献   
178.
The aim of this study was to evaluate the water quality of the Cértima River basin (Central Portugal). For that purpose, surface water samples were collected in March, May and July 2003, at 10 selected sampling sites, and were analysed for physicochemical parameters, namely temperature, conductivity, pH, total suspended solids, dissolved oxygen, biochemical oxygen demand (BOD5), Kjeldahl nitrogen and total phosphorus. Results revealed an acceptable water quality during the spring season. Maxima of 64 mg dm−3 for BOD5, 39 mg dm−3 for Kjeldahl nitrogen, and 5.2 mg dm−3 for total phosphorus, were recorded during summer, indicating a significant degradation of the water quality in a river stretch located downstream of the town of Mealhada. These values, which did not comply with the objectives of minimum quality for surface waters prescribed by the Portuguese legislation, were related to domestic wastewater discharges and runoff waters from a cattle farm. Besides their effects on the middle stretch of the river, these pollution sources were the most likely cause of the high nutrient load in downstream waters, and thus may have a major impact on the trophic status of Pateira de Fermentelos, a sensitive wetland area located in the lower Cértima basin.  相似文献   
179.
Natura 2000 is a network of natural sites whose aim is to preserve species and habitats of relevance in the European Union. The policy underlying Natura 2000 has faced widespread opposition from land users and received extensive support from environmentalists. This paper addresses the ethical framework for Natura 2000 and the probable moral assumptions of its main stakeholders. Arguments for and against Natura 2000 were analyzed and classified according to “strong” or “weak” versions of the three main theories of environmental ethics – anthropocentrism, biocentrism, and ecocentrism. Weak (intergenerational) anthropocentrism was found to underlie the Natura 2000 network itself and the positions of environmentalists, while strong (traditional) anthropocentrism pervaded the positions of economic developers. Land users seemed to fall somewhere between weak and strong anthropocentrism. The paper discusses the relation between ethics and different attitudes towards Natura 2000, highlighting some of the implications for the network’s ongoing implementation. It is shown that Natura 2000 achieves a strong reversal of the burden of proof from conservation to economic development and land use change under anthropocentrism. It is argued that the alleged theoretical divide between anthropocentrism and non-anthropocentrism in relation to the burden of proof does not seem to hold in practice. Finally, it is predicted that the weak versions of anthropocentrism, biocentrism, and ecocentrism, are likely to converge extensively in respect to nature conservation policy measures.“Charting the depths of law and policy disputes yield an understanding of ethical differences.” Paul B. Thompson (2002, p. 189).  相似文献   
180.

The purpose of this article is to analyze the challenges to, and opportunities for, increasing sustainable development (SD) co-benefits delivered by clean development mechanism (CDM) wind power projects in northeastern Brazil and the resulting implications for climate and energy policies. Five methodological phases were met: First, a documentary research was conducted in the main CDM database; second was a literature review, creating the analytical framework and a survey questionnaire needed to assess the SD co-benefits from the projects; third, documentary research was used to enable ex-ante analysis of the SD co-benefits proposed in the CDM Project Design Documents (PDDs); fourth, survey allowed for the analysis of SD co-benefits perceived by project entrepreneurs (ex-post analysis); and finally, a comparison between the ex-ante and ex-post analyses was completed. The results show the importance of carrying out SD co-benefit studies after the implementation of CDM projects in order to learn lessons for new mechanisms of climate governance. The lowest SD co-benefits were water management improvement in the project influence area, soil pollution prevention, health and safety improvements and technology transfer. The greatest opportunities for increasing SD co-benefits come from the environmental licensing process and the strengthening of Corporate Social Responsibility. The greatest challenges are new technology development, stakeholders’ engagement and SD co-benefit audits. We conclude that the improvement of multi-level climate and energy governance plays a key role in increasing SD co-benefits.

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