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201.
Fraser McLeod Gunes Erdogan Tom Cherrett Tolga Bektas Nigel Davies Duncan Shingleton Chris Speed Janet Dickinson Sarah Norgate 《Waste management (New York, N.Y.)》2014,34(2):273-280
Collection costs associated with servicing a major UK charity’s donation banks and collecting unsold goods from their retail shops can account for up to 20% of the overall income gained. Bank and shop collections are commingled and are typically made on fixed days of the week irrespective of the amounts of materials waiting to be collected. Using collection records from a major UK charity, this paper considers what vehicle routing and scheduling benefits could accrue if bank and shop servicing requirements were monitored, the former using remote sensing technology to allow more proactive collection scheduling. A vehicle routing and scheduling algorithm employing tabu search methods was developed, and suggested time and distance savings of up to 30% over the current fixed schedules when a minimum bank and shop fill level of between 50% and 60% was used as a collection trigger. For the case study investigated, this led to a potential revenue gain of 5% for the charity and estimated CO2 savings of around 0.5 tonnes per week across the fleet of six heterogeneous vehicles. 相似文献
202.
Daniel Ragnvaldsson Magnus Bergknut Jeffrey Lewis Stina Drotz Anton Lundkvist Kent Abrahamsson Sten Fernerud 《Environmental Chemistry Letters》2014,12(3):443-447
When exposed to the weather, sulfidic minerals release sulfuric acid, metals and metalloids. This leachate can devastate nearby ecosystems for centuries. This article reports a novel barrier system based on green liquor dregs that reduces acid generation, is inexpensive, and is practical for implementation at operational mines. Two waste rock piles were constructed. One pile was left open to the atmosphere, and the other was sealed with green liquor dregs and partially capped with a polyethylene liner. This test was designed in collaboration with personnel from Boliden Mineral AB, a Swedish mining company in order to ensure that the results would be practical to implement at an operational mine. Leachate flow and chemistry were monitored in both piles over a period of 12 months. Effluent volume was 40 % lower in the test pile, while thirteen of the twenty elements assessed showed average concentrations that were 50 % lower in the test pile than in the control pile. For the most environmentally toxic elements As, Cd, Pb and Hg, reductions were even more significant, ranging between 67 and 87 %. These positive results are hypothesized to be primarily due to the chemical and physical characteristics of the green liquor dregs. The novelty of this result is that it is the first barrier system that fulfills the multiple needs of the Swedish mining industry: It is effective in reducing acid mine drainage while remaining both economical and practical. No other barrier system meets these requirements. 相似文献
203.
Michal Petr L. G. J. Boerboom Duncan Ray Anne van der Veen 《Regional Environmental Change》2016,16(4):1161-1170
Information helps decision makers to address and to decide about environmental problems. In the context of climate change adaptation, often knowledge is missing on how the available information from impact models affects the decision-making process. The main aim of this study was to explore the extent of ambiguity and how new climate change information influenced decision of forest planners. We investigated changes in decisions of planners about forestry actions representing species choice and forest tourism and expiry dates of these actions leading to environmental constraints in the provision of ecosystem services. Forest planners evaluated expiry dates using four forest ecosystem services: forest production, stand yield class, sequestered carbon, and potential tourism. Data were collected during workshops with eleven forest planners from three forest districts in Scotland. Presented climate change information modified the understanding and frames of planners about forestry actions assessed with accompanying expiry dates. Changes in the frames of planners often result in both earlier and later expiry dates. Ambiguity of planners was found to be dependent on diversity in frames and difficulty in evaluating multiple ecosystem services. These findings imply that due to ambiguity forest planners might find it hard to choose climate change adaptation measures and researchers can struggle to convince planners with new research findings. 相似文献
204.
James N. Derr Philip W. Hedrick Natalie D. Halbert Louis Plough Lauren K. Dobson Julie King Calvin Duncan David L. Hunter Noah D. Cohen Dennis Hedgecock 《Conservation biology》2012,26(6):1130-1136
Hybridization between endangered species and more common species is a significant problem in conservation biology because it may result in extinction or loss of adaptation. The historical reduction in abundance and geographic distribution of the American plains bison (Bison bison bison) and their recovery over the last 125 years is well documented. However, introgression from domestic cattle (Bos taurus) into the few remaining bison populations that existed in the late 1800s has now been identified in many modern bison herds. We examined the phenotypic effect of this ancestry by comparing weight and height of bison with cattle or bison mitochondrial DNA (mtDNA) from Santa Catalina Island, California (U.S.A.), a nutritionally stressful environment for bison, and of a group of age‐matched feedlot bison males in Montana, a nutritionally rich environment. The environmental and nutritional differences between these 2 bison populations were very different and demonstrated the phenotypic effect of domestic cattle mtDNA in bison over a broad range of conditions. For example, the average weight of feedlot males that were 2 years of age was 2.54 times greater than that of males from Santa Catalina Island. In both environments, bison with cattle mtDNA had lower weight compared with bison with bison mtDNA, and on Santa Catalina Island, the height of bison with cattle mtDNA was lower than the height of bison with bison mtDNA. These data support the hypothesis that body size is smaller and height is lower in bison with domestic cattle mtDNA and that genomic integrity is important for the conservation of the American plains bison. Efectos Fenotípicos del ADN Mitocondrial de Ganado en el Bisonte Americano 相似文献
205.
The variety of ideas about ways nature is ‘valued’ in public policymaking are investigated. A theoretical ideational approach is combined with empirical analysis of the UK’s ecosystem services framework. Several types of ideas are identified, and how they interact is examined: ideas about nature itself; about the role that different research on the value of nature can or should play in decision-making; and about how policy decisions are made. In particular, the ways these ideas appear in academic debates, especially in ecological economics and philosophy, are confronted with how ideas appear in the policy practice of employing a ‘valuing nature’ concept. This reveals political dynamics sometimes missed by both advocates and critics of the concept of ecosystem services, such as the importance of promoting organisations and their agendas and activities, persuading different actors to change positions, and institutional commitments and sunk costs. 相似文献
206.
207.
Elena Cantarello Adrian C. NewtonRoss A. Hill Natalia Tejedor-GaravitoGuadalupe Williams-Linera Fabiola López-BarreraRobert H. Manson Duncan J. Golicher 《Ecological modelling》2011,222(5):1112-1128
Examining the potential for ecological restoration is important in areas where anthropogenic disturbance has degraded forest landscapes. However, the conditions under which restoration of degraded tropical dry forests (TDF) might be achieved in practice have not been determined in detail. In this study, we used LANDIS-II, a spatially explicit model of forest dynamics, to assess the potential for passive restoration of TDF through natural regeneration. The model was applied to two Mexican landscapes under six different disturbance regimes, focusing on the impact of fire and cattle grazing on forest cover, structure and composition. Model results identified two main findings. First, tropical dry forests are more resilient to anthropogenic disturbance than expected. Results suggested that under both a scenario of small, infrequent fires and a scenario of large, frequent fires, forest area can increase relatively rapidly. However, forest structure and composition differed markedly between these scenarios. After 400 years, the landscape becomes increasingly occupied by relatively shade-tolerant species under small, infrequent fires, but only species with both relatively high shade tolerance and high fire tolerance can thrive under conditions with large, frequent fires. Second, we demonstrated that different forms of disturbance can interact in unexpected ways. Our projections revealed that when grazing acts in combination with fire, forest cover, structure and composition vary dramatically depending on the frequency and extent of the fires. Results indicated that grazing and fire have a synergistic effect causing a reduction in forest cover greater than the sum of their individual effects. This suggests that passive landscape-scale restoration of TDF is achievable in both Mexican study areas only if grazing is reduced, and fires are carefully managed to reduce their frequency and intensity. 相似文献
208.
Jean T. Ellis Joseph P. Spruce Roberta A. Swann James C. Smoot Kent W. Hilbert 《Journal of Coastal Conservation》2011,15(1):139-149
The purpose of this research is to quantify and assess geospatial land-use and land-cover (LULC) changes in the coastal counties
of Mobile and Baldwin, Alabama using nine Landsat images from 1974–2008. A study-specific classification scheme was devised
comprising upland herbaceous, upland forest, non-woody and woody wetlands, open water, and urban categories. Upland forest
was the most dominant terrestrial cover type. Wetlands averaged 17% and urban averaged 7%. A majority of the urban expansion
occurred between 1974 and 1979 (26%). Thirty-four percent of the 2008 urban areas were upland forest in 1974. Watershed-scale
analysis of Three Mile Creek and D’Olive Bay highlights the temporal and spatial differences of urbanization for watersheds
found within the same region. This study is a Gulf of Mexico Alliance (GOMA) Application Pilot project that uses NASA data
products to benefit coastal environmental managers and community members. Results have led to increased effectiveness of coastal
conservation decision-making, increased understanding of post-hurricane LULC change, continued research on habitat change
impacts, and contributed to timely conservation planning efforts. This study has benefited the development of watershed management
plans by the Mobile Bay National Estuary Program, which is especially important given projected climate change. 相似文献
209.
210.