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51.
Landfilling is a fundamental step in any waste management strategy, but it can constitute a hazard for the environment for a long time. The need to protect the environment from potential landfill emissions makes risk assessment a decision tool of extreme necessity. The heterogeneity of wastes and the complexity of physical, chemical and biological processes that occur in the body of a landfill need specific procedures in order to evaluate the groundwater risk for the environment. Given the complexity of the composition of landfill leachates, the exact contribution of each potential toxic substance cannot be known precisely. Some reference contaminants that constitute the hazard (toxicity) of leachate have to be found to perform the risk assessment. A preliminary ecotoxicological investigation with luminescent bacteria has been carried out on different leachates from traditional and sustainable landfills in order to rank the chemicals that better characterize the leachate (heavy metals, ammonia and dissolved organic content). The attention has been focused on ammonia because it is present in high concentration and can last for centuries and can seriously contaminate the groundwater. The results showed that the toxicity of the leachate might reliably depend on the ammonia concentration and that the leachate toxicity is considerably lower in sustainable landfills where the ammonia had been degraded. This has an important consequence because if the containment system fails (as usually occur within 30-50yr), the risk of groundwater contamination will be calculated easier only in terms of the probability that the ammonia concentration is higher than a reference concentration.  相似文献   
52.
The presence of geranyl octanoate, previously found in pheromone gland extracts of Agriotes lineatus females, was also demonstrated in gland extracts of A. proximus females. Similar to A. lineatus, geranyl butanoate was present only in trace amounts in A. proximus female gland extracts. In air entrainment samples of female A. lineatus and A. proximus beetles, the relative ratio of geranyl butanoate and geranyl octanoate was higher than that in gland extracts. In addition, comparison of a segment of the mitochondrial cytochrome c oxidase subunit I gene of feral specimens of A. lineatus and A. proximus showed >99% similarity. Both pheromone profile and nucleotide sequence analysis delineate close relationship between the investigated taxa and postulate taxonomic revision. Further studies on sympatric populations of A. lineatus and A. proximus are underway to investigate and better understand possible processes of species diversification.  相似文献   
53.
Environmental Geochemistry and Health - Civilian and military shooting range facilities cause environmental issues in several countries due to the accumulation of Potentially Toxic Elements; as a...  相似文献   
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Two important gaps remain to be filled in the idiosyncratic deals (i‐deals) literature. First, it is unclear which employees are predisposed to seek and receive i‐deals. Second, it is unclear how employees' perceptions of whether their coworkers are receiving i‐deals affect their own i‐deal experiences. This study proposed a theoretical model suggesting that (a) three key motivational goals identified in human development research, that is, achievement, status, and communion striving, predispose employees to seek and receive i‐deals; (b) employees' perceptions of whether their coworkers are receiving i‐deals moderate these relationships; and (c) employees' i‐deals are related to their job behavior. Data collected from more than 400 working adults in Italy showed that employees' motivational goals (particularly achievement and status striving) were positively related to the levels of i‐deals they received, and that these i‐deals were in turn positively related to supervisors' assessments of their in‐role job performance, voice behavior, and interpersonal citizenship behavior. High perceptions of the extent to which coworkers received i‐deals further strengthened the relationship between status striving and employees' perceptions of their own i‐deals, highlighting a trait‐situation interactionist perspective on employees' i‐deal experiences. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
56.
This article explores certain aspects related to the environmental ethical message in the Encyclical Letter Laudato si, written in 2015 by Pope Francis, leader of the Catholic Church, and compares them to recent Green party political movements in Italy. Italy offers a unique case study in that the religious background of the country acts as an independent variable with respect to the social acceptance of current environmental issues. The ethical message in Laudato sì is compared to recent debates on the moral responsibility of the individual and/or institution towards environmental problems; a range of responsibilities assumed by institutions versus individuals with regards to environmental problems are analyzed. In conclusion, parallels are made between the abovementioned ethical debate and the ethical contents of the Encyclical Letter.  相似文献   
57.
Carotenoid-based ornaments act as signals of quality in many animal species. In contrast to feathers, which are relatively stable structures, carotenoid-pigmented integuments (e.g. bills, lores, tarsi) can change colour rapidly and may better reflect changes in physiological condition. I studied the seasonal variations in plasma carotenoids in red-legged partridges (Alectoris rufa) kept on a constant diet and free of intestinal parasites. Furthermore, I analyzed whether seasonal changes in circulating carotenoids were mirrored by the carotenoid-based coloration of eye rings and bill of this species. Plasma carotenoids showed seasonal variation, with higher levels coinciding with the end of the mating and the start of the laying season. Eye ring pigmentation was related to plasma carotenoid levels, and changes in bill hue (but not changes in UV or red bill chroma) mirrored the variation in plasma carotenoids during the breeding season. Despite the seasonal variation, individual differences in eye ring pigmentation and bill hue, UV and red chroma were consistent throughout the breeding season. Similarly, individual differences in eye ring pigmentation and bill hue and red chroma remained consistent between consecutive years. These results suggest that carotenoid based integumentary colorations act as dynamic traits that accurately reflect the carotenoid-status of individuals, thus reliably indicating consistent differences in individual quality. Furthermore, variability in signal expression appears to have a relevant genetic/phenotypic basis independently of environmental conditions. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
58.
The distribution and population structure of the eurybathic gorgonian Corallium rubrum were studied off Cap de Creus (Costa Brava, Northwestern Mediterranean Sea). Red coral is endemic to the Mediterranean Sea and the adjacent NE Atlantic coast, where it has been over exploited for centuries. This study presents, the first quantitative data on the spatial distribution and structure of a population extending between 50 (common SCUBA limits) and 230 m depth, and compared it with shallow populations previously studied in the same area. Different remotely operated vehicles (ROV) and two methodological approaches were employed during four cruises between 2002 and 2006: 1-Extensive surveys: sea to coast transects in which red coral density and patch frequency were recorded; 2-Intensive surveys, in which parameters describing colony morphology were recorded. Most of the hard substrate between 50 and 85 m depth was inhabited by red coral colonies, showing a patch frequency of 8.3 ± 7.9 SD patches per 100 m-transect (total transect area: 34 m2), and within-patch colony densities of 16–376 colonies m−2 (mean of 43 ± 53 colonies m−2). Below 120 m depth red coral was less abundant, and rather than forming dense patches as in shallow water, isolated colonies were more common. The population structure differed between sites that are easily accessible to red coral fishermen, and remote ones (both at similar depth, 60–80 m), as colonies in easily accessible locations were smaller in height and diameter, and showed a less developed branching pattern. At shallower locations (10–50 m depth) the population structure was significantly different from those at deeper locations, due to the heavy harvesting pressure they are exposed to in the shallows. Twenty-five to forty-six percentage of the deeper colonies were taller than 6 cm, while only 7–16% of the shallow water colonies exceeded 6 cm colony height. Forty-six to seventy-nine percentage of the colonies in deeper waters were large enough to be legally harvested, while only 9–20% of the shallow water colonies met the 7 mm legal basal diameter to be collected. The branching pattern was also better developed in deeper colonies, as up to 16% of the colonies showed fourth order branches, compared to less than 1% of the shallow water colonies (of which 96% consisted of only one single branch). The results thus confirm that C. rubrum populations above 50 m depth are exposed to a higher harvesting intensity than deeper populations in the same area.  相似文献   
59.
The process of raising public awareness around the world concerning the need to apply criteria of sustainable development was basically set in motion at the Rio de Janeiro Summit in 1992. There it was decided that the most suitable context for fostering the process is the local level, and the Local Action Plan forms a basic element in this process.Some preliminary studies have shown the evidence of great advancement in the creation of Local Action Plans in municipalities. However, their execution is frequently paralyzed by a lack of necessary resources and suitable State policies.The aim of this paper is to verify the effect that different factors might have on the degree of progress made by the Local Action Plan in the municipalities of the European Union.The results show that the public works policies of the EU and the governments of the member states fail to impact the level of commitment of municipal governments; however, when the supporting policy originates from administrations closer to the municipality and are made concrete in the form of economic support and technical advice, they prove to be relevant. Strictly political factors, such as stability, have a more limited yet significant effect on the execution of Local Action Plans.  相似文献   
60.
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