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891.
Radio tracking of 142 males captured at 44 leks in Spain showed that partial migration of great bustard males in summer is a widespread behaviour in many Iberian populations, in contrast to their previously assumed sedentariness. A variable number of males migrated immediately after mating to summering areas with lower temperatures and human population densities and more trees and rainfall levels than the breeding sites. Birds selected there fields with trees and sunflower crops which provided shade during the hottest midday hours and protective cover against predators. Males breeding in areas with higher July temperatures had a higher tendency to migrate, and males from hotter, southern regions migrated longer distances than those from milder, northern regions and showed a preferred northward direction. These results confirmed various predictions from the weather sensitivity hypothesis, suggesting that summer migration of great bustard males represents primarily an adaptation to escape the summer heat of most breeding areas in central and southern Iberia. The hypothesis that males migrated to benefit from higher food availability at the summering areas could not be rejected by our results. Finally, migrating males also gained more tranquillity during the post-breeding moult due to the lower human population density at the summering areas. Summer migration of Iberian great bustard males may thus be interpreted as a form of behavioural thermoregulation which has not been described for other Palaearctic populations of this species or for other bird species breeding in temperate latitudes.  相似文献   
892.
The environmental and social impact derived from treated wastewater reuse is an intrinsically complex multidimensional process, which involves multiple criteria and multiple stakeholders. This paper presents the use of multicriteria decision through the TOPSIS method, applied to six different methodologies concerning the disinfection of treated wastewater before reusing. Results have shown that the best disinfection technique for treated wastewater has been chlorination with 4 ppm, if this water is to be destined to an urban, agricultural or industrial use, due to a large weight given to cost and environmental criteria. Conversely, in recreational and environmental uses, the alternative of ultraviolet light disinfection was the chosen alternative. Economic criteria showed priority in the most entrepreneurial uses of the water, although social and political cost had a greater weight in the case of environmental or recreational uses. The inclusion of environmental and social assessment in the disinfection technique decision support clearly provides a cleaner and more sustainable production.  相似文献   
893.
The significance of waste management systems in recent years increased due to the growing problems of waste management chains affecting the daily lives of millions of people and the impact on the environment. Several promising approaches have been developed in the past few years. One of them is the waste management system modelling using reliability, availability, maintainability and safety software. This paper analyses and evaluates this approach. The main goal is to provide quantitative forecasts for various performance measures of waste management systems. They include availability, downtimes, number of failures, and cost. Evaluation of these measures is important for optimal decision making. The system design should both maximise the system performance leading to cleaner processing and minimise the overall cost within the allowable constraints. The effectiveness of this methodology is demonstrated through a case study.  相似文献   
894.
The impact of environmental practices on firm performance raises an ongoing debate in which the review of the existing literature yields no conclusive results. Different methods have been used to study this relationship and most of the analyses have focused on manufacturing companies. This paper examines the link between environmental practices and firm performance in the Spanish hotel industry using two methods: a cluster analysis and a regression analysis. First, three groups were defined according to their environmental proactivity, and hotels showing a stronger commitment to environmental practices proved to reach higher performance levels. Second, through the regression analysis, findings showed that environmental practices impact significantly on several performance variables.  相似文献   
895.
Life Cycle Assessment (LCA) is a well-known tool for analyzing environmental impacts on a wide perspective with reference to a product system and the related environmental and economic impacts. The need for a novel approach that complements environmental and financial considerations is addressed in this study with the introduction of a new graphical representation: the Environmental Performance Strategy Map. This graphical map allows one to combine the main environmental indicators (footprints) with the additional dimension of cost. The paper defines the Sustainable Environmental Performance Indicator as a single measure for sustainability of a given option. Comparison of different options for strategic decision-making purposes can be enhanced and facilitated by the use of this indicator.  相似文献   
896.
Currently, issues related with climate change, security of energy supply, energy efficiency and sustainability are at the core of all energy policies and strategies. The current technologies are not able to face this challenge; therefore, the development of new and more sustainable energy technologies must be supported.As part of this, energy technology assessment tools can help decision-makers in the identification and evaluation of sustainable energy solutions, in order to integrate them in long term energy strategies.The EMINENT tool was developed to assess the performance and market potential of early stage technologies (EST) in a pre-defined energy chain, under national conditions, in terms of financial, energy and environmental criteria.This paper presents a comparative study between EMINENT and other tools for energy technology assessment. The tools analysed were CO2DB, MARKAL, IKARUS and E3Database.Although there are many different energy technology assessment tools, EMINENT seems to be the only one targeting EST.  相似文献   
897.
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   
898.
Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.  相似文献   
899.
Environmental Chemistry Letters - Rising adverse impact of climate change caused by anthropogenic activities is calling for advanced methods to reduce carbon dioxide emissions. Here, we...  相似文献   
900.
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