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31.
This paper examines the role and diffusion of corporate social responsibility (CSR) management, especially in relation with the adoption of other management systems, in small and medium sized companies in the surface mining industry in Catalonia (Spain). Specifically, it identifies the most salient CSR practices, procedures and metrics and the profiles of companies more prone to adopt them. To fulfill this aim, a survey has been conducted. Results show that mining companies are familiar with CSR practices, but there is not much formalization of procedures and measurement systems of CSR yet. Results show that the majority of socially responsible practices are related to environmental issues and therefore there is a relation between CSR and the application of environmental management systems. The analysis reveals that the management of CSR activities improves with the diffusion of knowledge on CSR practices. A second survey collected the opinion of professional associations in the sector. Respondents indicate that an improvement in CSR management will lead to a better global competitive position.  相似文献   
32.
A particle-tracking model based on high-resolution ocean flow data was used to investigate particle residence times and spatial distribution of settling sediment for two geo-morphologically different Swedish coastal areas. The study was a part of a safety assessment for the location of a future nuclear-waste repository, and information about the particle-transport patterns can contribute to predictions of the fate of a possible leakage. It is also, to our knowledge, the first time particle-transport differences between two coastal areas have been quantified in this manner. In Forsmark, a funnel-shaped bay shielded by a number of islands, the average residence time for clay particles was 5 times longer than in the modeled part of Simpevarp, which is open to the Baltic Sea. In Forsmark, <10 % of the released particles left the domain compared to 60–80 % in Simpevarp. These site-specific differences will increase over time with the differences in land uplift between the areas.  相似文献   
33.
Kovács A  Mammen UC  Wernham CV 《Ambio》2008,37(6):408-412
Sixty-four percent of the 56 raptor and owl species that occur in Europe have an unfavorable conservation status. As well as requiring conservation measures in their own right, raptors and owls function as useful sentinels of wider environmental "health," because they are widespread top predators, relatively easy to monitor, and sensitive to environmental changes at a range of geographical scales. At a time of global acknowledgment of an increasing speed of biodiversity loss, and new, forward-looking and related European Union biodiversity policy, there is an urgent need to improve coordination at a pan-European scale of national initiatives that seek to monitor raptor populations. Here we describe current initiatives that make a contribution to this aim, particularly the current "MEROS" program, the results of a questionnaire survey on the current state of national raptor monitoring across 22 BirdLife Partners in Europe, the challenges faced by any enhanced pan-European monitoring scheme for raptors, and some suggested pathways for efficiently tapping expertise to contribute to such an initiative.  相似文献   
34.
Myrtus communis, Arbutus unedo and Retama sphaerocarpa are Mediterranean shrubs widely used in revegetation of semiarid degraded soils. The aim of this work is to study the resistance of these plants to arsenic under controlled conditions, in order to evaluate their potential use in revegetation and/or phytoremediation of As-polluted soils. R. sphaerocarpa showed higher resistance to As than M. communis or A. unedo according to its higher EC50, P status and P/As molar ratio in both, roots and shoots, and the lower increases in lipid peroxidation and decrease of chlorophyll levels in response to arsenic, while the highest arsenate sensitivity was obtained for A. unedo. Arsenic was mainly retained in roots, and, although M. communis accumulated higher arsenic amounts than the other two species, R. sphaerocarpa showed the highest root to shoot transfer. Most of the studied parameters (chlorophylls, MDA and total thiols) showed significant correlation with arsenic concentration in roots and leaves of plants, so they can be useful indexes in the diagnosis of arsenic toxicity in these species. According to our results, both M. communis and R. sphaerocarpa could be used in the revegetation of moderately arsenic contaminated sites.  相似文献   
35.
Tanning processes performed in drums consume large amounts of water and chemicals, most of which end up in the wastewater. This study explores an alternative approach at an industrial scale to the traditional pickle-chrome tanning method. The new method replaces formic and sulphuric acids with sulphonic aromatic acid. Because it is done without float, there is a sizeable reduction in the amount of added salt and chrome salt as well as an increase in temperatures at the end of the tanning process. From an environmental perspective, the new method offers important advantages. For instance, there is no float addition in the tannage. Also, there are reductions of 94% and 99%, respectively, in the discharge of chlorides and chrome, as well as a 75% reduction in the residual float. Our financial assessment demonstrated that the new method is 42% cheaper than a traditional approach.  相似文献   
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Increasing levels of Heracleum persicum (golpar) in drinking water were studied in broilers. Two hundred and forty-one-day-old male chickens were allocated to one of six treatments: control, without added phytogenics nor probiotics in drinking water, and probiotics at recommended manufacturer’s level (P) or 1.0, 1.5, 2.0, and 2.5 ml/l of golpar extract solution (G1, G1.5, G2, and G2.5 treatments, respectively) in drinking water. As a result of this study, no linear or quadratic trends in the feed intake (FI) and feed conversion rate (FCR) due to golpar supplementation were found. Body weight gain, final body weight, and relative carcass weight showed a positive linear response with increasing levels of golpar supplementation. Neither golpar nor probiotics had effects on the percentages of edible parts of the carcass. Golpar supplementation levels caused a linear negative response of the albumin content in blood plasma, whereas both abdominal fat as percentage of carcass weight and uric acid levels in blood plasma linearly increased. The effects on Ig responses were only observed at 42 days of age and were similar in probiotics and the highest level of golpar supplementation. Based on our results, both probiotics and golpar supplementation could improve broiler performance and immune function.  相似文献   
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