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871.
Research shows that public commitment making helps promote pro-environmental behavior. However, not everyone may be willing to make such commitments. Therefore, it is important to investigate the conditions under which commitment making is likely to occur. We expected dispositional trust and situational expectations to determine the willingness to install a system of public commitments. Two studies are presented which show that group members low in dispositional trust (low trusters) are likely to choose for a public commitment system when their situational expectations concerning other group members' contributions are high, while those high in dispositional trust (high trusters) are likely to choose for a public commitment system when their situational expectations concerning other group members' contributions are low. It appears that for both low and high trusters the choice for a system of public commitments is instigated by a motivation to further the collective outcomes. 相似文献
872.
Hayo M.G. van der Werf Claver Kanyarushoki Michael S. Corson 《Journal of environmental management》2009,90(11):3643-3652
This paper describes and applies EDEN-E, an operational method for the environmental evaluation of dairy farms based on the life cycle assessment (LCA) conceptual framework. EDEN-E requires a modest amount of data readily available on-farm, and thus can be used to assess a large number of farms at a reasonable cost. EDEN-E estimates farm resource use and pollutant emissions mostly at the farm scale, based on-farm-gate balances, amongst others. Resource use and emissions are interpreted in terms of potential impacts: eutrophication, acidification, climate change, terrestrial toxicity, non-renewable energy use and land occupation. The method distinguishes for each total impact a direct component (impacts on the farm site) and an indirect component (impacts associated with production and supply of inputs used). A group of 47 dairy farms (41 conventional and six organic) was evaluated. Expressed per 1000 kg of fat-and-protein-corrected milk, total land occupation was significantly larger for organic than for conventional farms, while total impacts for eutrophication, acidification, climate change, terrestrial toxicity, and non-renewable energy use were not significantly different for the two production modes. When expressed per ha of land occupied all total impacts were significantly larger for conventional than organic farms. This study largely confirms previously published findings concerning the effect of production mode on impacts of dairy farms. However, it strikingly reveals that, for the set of farms examined, the contribution of production mode to overall inter-farm variability of impacts was minor relative to inter-farm variability within each of the two production modes examined. The mapping of impact variability through EDEN-E opens promising perspectives to move towards sustainable farming systems by identifying the structural and management characteristics of the farms presenting the lowest impacts. 相似文献
873.
Traffic mortality and the role of minor roads 总被引:1,自引:0,他引:1
van Langevelde F van Dooremalen C Jaarsma CF 《Journal of environmental management》2009,90(1):660-667
Roads have large impacts on wildlife, as they form one of the principal causes of mortality, and disturbance and fragmentation of habitat. These impacts are mainly studied and mitigated on major roads. It is, however, a widespread misconception that most animals are killed on major roads. In this paper, we argue that minor roads have a larger impact on wildlife with respect to habitat destruction, noise load and traffic mortality. We use data on traffic related deaths in badgers (Meles meles) in The Netherlands to illustrate that traffic mortality is higher on minor roads. We ask for a more extensive investigation of the environmental impacts of minor roads. Moreover, we argue that the success of mitigation on roads drastically increases when both major and minor roads are integrated in the planning of traffic flows. Therefore, we propose a strategy based on the concept of a "traffic-calmed area". Traffic-calmed areas create opportunities for wildlife by decreasing limitations for animal movement. We ask for further studies to estimate what size traffic-calmed areas should be to maintain minimum viable animal populations. 相似文献
874.
Jeroen M.M. Neuvel Adri van den Brink 《Journal of Environmental Planning and Management》2009,52(7):865-880
Spatial planning is increasingly regarded as an important instrument to reduce flood consequences. Nevertheless, there are very few studies that show why local planning authorities do or do not systematically use spatial planning in advance to mitigate flood risks. This paper explores flood reduction strategies in local planning practices in the Netherlands. It also explores why spatial planning was or was not used to reduce flood consequences. The arguments for the use or non-use of planning mainly referred to requirements from other governmental bodies and the perceived role and the related responsibility of local planning authorities, previous disaster experience, and previous experience with spatial planning for flood risk management. 相似文献
875.
876.
877.
Innovative separation and beneficiation techniques of various materials encountered in electrical and electronic equipment wastes (WEEE) is a major improvement for its recycling. Mechanical separation-oriented characterisation of WEEE was conducted in an attempt to evaluate the amenability of mechanical separation processes. Properties such as liberation degree of fractions (plastics, metals ferrous and non-ferrous), which are essential for mechanical separation, are analysed by means of a grain counting approach. Two different samples from different recycling industries were characterised in this work. The first sample is a heterogeneous material containing different types of plastics, metals (ferrous and non-ferrous), printed circuit board (PCB), rubber and wood. The second sample contains a mixture of mainly plastics. It is found for the first sample that all aluminium particles are free (100%) in all investigated size fractions. Between 92% and 95% of plastics are present as free particles; however, 67% in average of ferromagnetic particles are liberated. It can be observed that only 42% of ferromagnetic particles are free in the size fraction larger than 20 mm. Particle shapes were also quantified manually particle by particle. The results show that the particle shapes as a result of shredding, turn out to be heterogeneous, thereby complicating mechanical separation processes. In addition, the separability of various materials was ascertained by a sink–float analysis and eddy current separation. The second sample was separated by automatic sensor sorting in four different products: ABS, PC–ABS, PS and rest product. The fractions were characterised by using the methodology described in this paper. The results show that the grade and liberation degree of the plastic products ABS, PC–ABS and PS are close to 100%. Sink–float separation and infrared plastic identification equipment confirms the high plastic quality. On the basis of these findings, a global separation flow sheet is proposed to improve the plastic separation of WEEE. 相似文献
878.
879.
Pietro Galgani Ester van der Voet Gijsbert Korevaar 《Waste management (New York, N.Y.)》2014,34(12):2454-2465
In some areas of Sub-Saharan Africa appropriate organic waste management technology could address development issues such as soil degradation, unemployment and energy scarcity, while at the same time reducing emissions of greenhouse gases. This paper investigates the role that carbon markets could have in facilitating the implementation of composting, anaerobic digestion and biochar production, in the city of Tamale, in the North of Ghana. Through a life cycle assessment of implementation scenarios for low-tech, small scale variants of the above mentioned three technologies, the potential contribution they could give to climate change mitigation was assessed. Furthermore an economic assessment was carried out to study their viability and the impact thereon of accessing carbon markets. It was found that substantial climate benefits can be achieved by avoiding landfilling of organic waste, producing electricity and substituting the use of chemical fertilizer. Biochar production could result in a net carbon sequestration. These technologies were however found not to be economically viable without external subsidies, and access to carbon markets at the considered carbon price of 7 EUR/ton of carbon would not change the situation significantly. Carbon markets could help the realization of the considered composting and anaerobic digestion systems only if the carbon price will rise above 75–84 EUR/t of carbon (respectively for anaerobic digestion and composting). Biochar production could achieve large climate benefits and, if approved as a land based climate mitigation mechanism in carbon markets, it would become economically viable at the lower carbon price of 30 EUR/t of carbon. 相似文献
880.
B. Van der Bruggen H. Goossens P.A. Everard K. Stemgée W. Rogge 《Journal of environmental management》2009,90(2):541-549
Softening drinking water before distribution yields advantages with environmental impact, such as lower household products consumption, less scaling in piping and machines, and the avoidance of decentralized, domestic softeners. Central softening is under consideration in Flanders by the largest water supplier, VMW (Dutch acronym for “Flemish Company for Water Supply”), to deliver soft (15 °F) water to their customers. A case study is presented for a region with hard water (47 °F). The chosen technique is the pellet reactor, based on precipitation of CaCO3 by NaOH addition. This softening operation has possibly large impact on the environment and the water consumption pattern.A cost-benefit analysis has been made to estimate the added value of central softening, by investigating the impact on the drinking water company, on their customers, on employment, on environment, on health, etc. The analysis for the region of study revealed benefits for customers which were higher than the costs for the drinking water company. However, pricing of drinking water remains an important problem.A sensitivity analysis of these results has also been made, to evaluate the impact of important hypothesis, and to be able to expand this study to other regions. The conclusions for this part show that softening is beneficial if water hardness is to be decreased by at least 5 °F. 相似文献