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241.
Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (northwestern Spain). We used orthoimages and a set of standard landscape metrics to determine transitions between land cover classes and to examine forest distribution patterns. Eucalypt plantations showed the greatest increase in area (197%) over time. Furthermore, transitions to eucalypt plantations were found in all major land cover classes. Forest showed a net decline of 20% in total area and represented 30% of the landscape area in 2003. Forest losses were mainly due to eucalypt plantations and the building of a water reservoir, while forest gains were due to increases in shrubland, meadows and cultivated fields which had been recolonised. Forest patch size and core area decreased, and edge length increased over time. In turn, increases were obtained in mean distance between forest patches, and in adjacency to eucalypt plantations and to a water reservoir. These results suggest an increase in forest fragmentation from 1957 to 2003, as well as a change in the nature of the habitat surrounding forest patches. This study shows that land use changes, mostly from eucalypt plantation intensification, negatively affected forested habitats, although some regeneration was ongoing through ecological succession from land abandonment.  相似文献   
242.
The effect of meteorological variables on surface ozone (O3) concentrations was analysed based on temporal variation of linear correlation and artificial neural network (ANN) models defined by genetic algorithms (GAs). ANN models were also used to predict the daily average concentration of this air pollutant in Campo Grande, Brazil. Three methodologies were applied using GAs, two of them considering threshold models. In these models, the variables selected to define different regimes were daily average O3 concentration, relative humidity and solar radiation. The threshold model that considers two O3 regimes was the one that correctly describes the effect of important meteorological variables in O3 behaviour, presenting also a good predictive performance. Solar radiation, relative humidity and rainfall were considered significant for both O3 regimes; however, wind speed (dispersion effect) was only significant for high concentrations. According to this model, high O3 concentrations corresponded to high solar radiation, low relative humidity and wind speed. This model showed to be a powerful tool to interpret the O3 behaviour, being useful to define policy strategies for human health protection regarding air pollution.  相似文献   
243.
A Best Available Techniques (BAT) analysis of a mussel canning processing facility in northwest Spain was undertaken to investigate potential cleaner production and efficiency improvements. Potential techniques were identified from the literature and from our experience in the seafood sector. BATs were then assessed for possible implementation in a mussel canning facility. This work describes, in considerable detail, the advantages and disadvantages of the techniques discussed.  相似文献   
244.
Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.  相似文献   
245.
Environmental Science and Pollution Research - Pharmaceuticals, such as dipyrone (DIP), paracetamol (PCT), and propranolol (PPN), are widely used analgesics and beta-blockers with the greatest...  相似文献   
246.
The construction sector is responsible for around 28% of the total waste volume generated in Europe, which exceeds the amount of household waste. This has led to an increase of different research studies focusing on construction waste quantification. However, within the research studies made, packaging waste has been analyzed to a limited extent. This article focuses on the packaging waste stream generated in the construction sector. To this purpose current on-site waste packaging management has been assessed by monitoring ten Mediterranean residential building works. The findings of the experimental data collection revealed that the incentive measures implemented by the construction company to improve on-site waste sorting failed to achieve the intended purpose, showing low segregation ratios. Subsequently, through an analytical study the generation patterns for packaging waste are established, leading to the identification of the prevailing kinds of packaging and the products responsible for their generation. Results indicate that plastic waste generation maintains a constant trend throughout the whole construction process, while cardboard becomes predominant towards the end of the construction works with switches and sockets from the electricity stage. Understanding the production patterns of packaging waste will be beneficial for adapting waste management strategies to the identified patterns for the specific nature of packaging waste within the context of construction worksites.  相似文献   
247.
 Penaeid shrimps comprise an important portion of the world's industrial fisheries and mariculture. In the Southwest Atlantic, Penaeus (Farfantepenaeus) subtilis, P. (F.) paulensis, P. (F.) brasiliensis and P. (Litopenaeus) schmitti are the most important commercially exploited species. Despite their high commercial value, there is little information available on the different aspects of their biology or genetics and almost no data on stock structure. Also, the taxonomic status of P. subtilis populations in relation to P. paulensis and their geographic ranges have been recently questioned. In this paper we used both nuclear (allozymes) and mitochondrial (cytochrome oxidase subunit 1) data to compare species of south-western Atlantic penaeids and to estimate their phylogenetic relationships. We could readily discriminate among the four main Brazilian penaeid species and detected a fifth, new, species of Penaeus. This new species corresponded to one of the described morphotypes of P. subtilis. Based on these analyses, the geographic ranges of P. subtilis and P. paulensis were clarified. Our data also support the conclusion of Baldwin et al. (1998) that the subgenus Farfantepenaeus is polyphyletic. Received: 6 January 2000 / Accepted: 13 June 2000  相似文献   
248.
249.
For decades, several native medicinal species have been used by the pharmaceutical industry in Brazil to create commercial products. In 1995, the Ministry of Health, following the recommendations of the World Health Organization, established herbal regulations (RDC 17) in order to improve the quality of such products. In fact, only plant species with conclusive results from pharmacological and toxicological studies can be used for creating medicines. In this study, we evaluated the consequences of RDC 17 on the use and conservation of native medicinal plants by comparing the plant material used by six companies in 1995/1996 and 10 years later (2005/2006). Eighty-three different species were used in 1995/1996, 50 of them native (60.2%), 16 exotic (19.3%), and 17 imported (20.5%). In 2005/2006, 44 species were used by the companies and only 19 (43.2%) were native. The category of plant material that saw the largest decrease in use was roots, and in 2005/2006 leaves were more used. The study shows a strong reduction in the collection of native species signalizing the importance of herbal regulations on their conservation. It also points to the need for pharmacological and toxicological studies of the Brazilian native medicinal flora, as well as studies on their ecology and conservation.  相似文献   
250.
The main goal of this paper is to obtain a granular material formulated with Municipal Solid Waste Incineration (MSWI) bottom ash (BA) and air pollution control (APC) fly ash to be used as secondary building material. Previously, an optimum concrete mixture using both MSWI residues as aggregates was formulated. A compromise between the environmental behavior whilst maximizing the reuse of APC fly ash was considered and assessed. Unconfined compressive strength and abrasion resistance values were measured in order to evaluate the mechanical properties. From these results, the granular mixture was not suited for certain applications owing to the high BA/APC fly ash content and low cement percentages used to reduce the costs of the final product. Nevertheless, the leaching test performed showed that the concentrations of all heavy metals were below the limits established by the current Catalan legislation for their reutilization. Therefore, the material studied might be mainly used in embankments, where high mechanical properties are not needed and environmental safety is assured.  相似文献   
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