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401.
Kate Millar Erik Thorstensen Sandy Tomkins Ben Mepham Matthias Kaiser 《Journal of Agricultural and Environmental Ethics》2007,20(1):53-63
A number of EU institutions and government committees across Europe have expressed interest in developing methods and decision-support
tools to facilitate consideration of the ethical dimensions of biotechnology assessment. As part of the work conducted in
the EC supported project on ethical tools (Ethical Bio-TA Tools), a number of ethical frameworks with the potential to support
the work of public policy decision-makers has been characterized and evaluated. One of these potential tools is the Delphi
method. The Delphi method was originally developed to assess variables that are intangible and/or shrouded in uncertainty
by drawing on the knowledge and abilities of a diverse group of experts through a form of anonymous and iterative consultation.
The method has hitherto been used by a diversity of practitioners to explore issues such as technology assessment, environmental
planning, and public health measures. From the original (classical) Delphi, a family of Delphi-related processes has emerged.
As a result of the evaluation of the various Delphi processes, it is proposed that the classical method can be further developed
and applied as a form of ethical framework to assist policy-makers. Through a series of exercises and trials, an Ethical Delphi
has been developed as a potential approach for characterizing ethical issues raised by the use of novel biotechnologies. Advantages
and disadvantages of the method are discussed. Further work is needed to develop the procedural aspects of the Ethical Delphi
method and to test its use in different cultural contexts. However, utilizing an ethical framework of this type combines the
advantages of a methodical approach to capture ethical aspects with the democratic virtues of transparency and openness to
criticism. Ethical frameworks such as the Ethical Delphi should contribute to better understanding of and decision-making
on issues that involve decisive ethical dimensions. 相似文献
402.
Choices of where to carry out everyday activities in large-scale environments were conceptualized as a process of forming ‘travel plans’, and, to test a model of how such plans are formed, three experimental simulations of a planning task were performed in the laboratory. In Experiment 1, subjects (high school students) were found to choose a shortest route to travel between a number of actual, familiar locations in a town by first choosing the order between the locations that minimized straight-line (Euclidean) distances, then choosing the shortest paths between the locations in the constrained order. The order choices were, in Experiment 2, found to be made by minimizing distance locally rather than globally, except in some cases when ‘spatial configurations’ of the locations were discovered. Both the results of this experiment and of Experiment 3 suggested that such discoveries were facilitated by a simultaneous representation of the locations which was possible when they were positions on a display, committed to short-term memory or available for perceptual inspection, but to a less extent when they were actual locations. 相似文献
403.
404.
Teresa I. Schueller Erik V. Nordheim Benjamin J. Taylor Robert L. Jeanne 《Die Naturwissenschaften》2010,97(11):1017-1022
This study explores whether or not foragers of the Neotropical swarm-founding wasp Polybia occidentalis use nest-based recruitment to direct colony mates to carbohydrate resources. Recruitment allows social insect colonies to rapidly exploit ephemeral resources, an ability especially advantageous to species such as P. occidentalis, which store nectar and prey in their nests. Although recruitment is often defined as being strictly signal mediated, it can also occur via cue-mediated information transfer. Previous studies indicated that P. occidentalis employs local enhancement, a type of cue-mediated recruitment in which the presence of conspecifics at a site attracts foragers. This recruitment is resource-based, and as such, is a blunt recruitment tool, which does not exclude non-colony mates. We therefore investigated whether P. occidentalis also employs a form of nest-based recruitment. A scented sucrose solution was applied directly to the nest. This mimicked a scented carbohydrate resource brought back by employed foragers, but, as foragers were not allowed to return to the nest with the resource, there was no possibility for on-nest recruitment behavior. Foragers were offered two dishes—one containing the test scent and the other an alternate scent. Foragers chose the test scent more often, signifying that its presence in the nest induces naïve foragers to search for it off-nest. P. occidentalis, therefore, employs a form of nest-based recruitment to carbohydrate resources that is mediated by a cue, the presence of a scented resource in the nest. 相似文献
405.
Murdiyarso Daniel Lilleskov Erik Kolka Randy 《Mitigation and Adaptation Strategies for Global Change》2019,24(4):493-505
Mitigation and Adaptation Strategies for Global Change - It is widely known that tropical peatlands, including peat swamp forests (PSFs), provide numerous ecosystem services in both spatial and... 相似文献
406.
407.
The input of acidity to Swedish forest soils through forestry between 1955 and 2010 is compared with the acid input from atmospheric deposition. Depending on region, input of acidity from forestry was the minor part (25–45%) of the study period’s accumulated acid input but is now the dominating source (140–270 molc ha−1 year−1). The net uptake of cations due to the increase in standing forest biomass, ranged between 35 and 45% of the forestry related input of acidity while whole-tree harvesting, introduced in the late 1990s, contributed only marginally (< 2%). The geographical gradient in acid input is reflected in the proportion of acidified soils in Sweden but edaphic properties contribute to variations in acidification sensitivity. It is important to consider the acid input due to increases in standing forest biomass in acidification assessments since it is long-term and quantitatively important.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01540-y. 相似文献
408.
In this perspective, we reflect upon the question: what processes may help transition scientific insights on sustainability issues into practice and thus contribute to tackling the complex, systemic sustainability problems of today? We use five forerunners in the field of providing and brokering knowledge for science informed real world solutions, all published in Ambio and highlighted in this Anniversary collection, as our starting point. We discuss how the authors present solutions, whom they tried to reach, and what was suggested—implicitly or explicitly—as the potential uptake processes for turning scientific knowledge into practice. With this as the starting point, we discuss how sustainability science, as a field vowed to action, has evolved in its views of actors, pathways for impacts, and the potential roles of research and researchers to promote sustainability transformations. 相似文献
409.
The transboundary Georgia Basin Puget Sound ecosystem is situated in the southwest corner of British Columbia and northwest comer of Washington State. While bountiful and beautiful, this international region is facing significant threats to its marine and freshwater resources, air quality, habitats and species. These environmental challenges are compounded by rapid population growth and attendant uiban sprawl. As ecosystem stresses amplified and partnerships formed around possible solutions, it became increasingly clear that the shared sustainability challenges in the Georgia Basin and Puget Sound required shared solutions. Federal, state and provincial institutional arrangements were made between jurisdictions, which formalized small scale interest in transboundary management of this ecosystem. Formal agreements, however, can only do so much to further management of an ecosystem that spans international boarders. A transboundary regional research meeting, the 2003 GB/PS Research Conference, opened the doors for large-scale informal cross-boarder cooperation and management. In addition to cooperation, continued efforts to stem toxic pollution, contain urban growth, and protect and restore ecosystems, require a commitment from scientists, educators and policy makers to better integrate research and science with decision-making.Former Director of Planning and of Special Projects in the British Columbia Ministry of Municipal Affairs. 相似文献
410.
Morgan Gerlitz Jimmy Fox William Ford Admin Husic Tyler Mahoney Mindy Armstead Susan Hendricks Angela Crain Jason Backus Erik Pollock Wei Ren Bo Tao Brenden Riddle David White 《Journal of the American Water Resources Association》2023,59(4):635-651
The Ohio River Basin (ORB) is responsible for 35% of total nitrate loading to the Gulf of Mexico yet controls on nitrate timing require investigation. We used a set of submersible ultraviolet nitrate analyzers located at 13 stations across the ORB to examine nitrate loading and seasonality. Observed nitrate concentrations ranged from 0.3 to 2.8 mg L−1 N in the Ohio River's mainstem. The Ohio River experiences a greater than fivefold increase in annual nitrate load from the upper basin to the river's junction with the Mississippi River (74–415 Gg year−1). The nitrate load increase corresponds with the greater drainage area, a 50% increase in average annual nitrate concentration, and a shift in land cover across the drainage area from 5% cropland in the upper basin to 19% cropland at the Ohio River's junction with the Mississippi River. Time-series decomposition of nitrate concentration and nitrate load showed peaks centered in January and June for 85% of subbasin-year combinations and nitrate lows in summer and fall. Seasonal patterns of the terrestrial system, including winter dormancy, spring planting, and summer and fall growing-harvest seasons, are suggested to control nitrate timing in the Ohio River as opposed to controls by river discharge and internal cycling. The dormant season from December to March carries 51% of the ORB's nitrate load, and nitrate delivery is high across all subbasins analyzed, regardless of land cover. This season is characterized by soil nitrate leaching likely from mineralization of soil organic matter and release of legacy nitrogen. Nitrate experiences fast transit to the river owing to the ORB's mature karst geology in the south and tile drainage in the northwest. The planting season from April to June carries 26% of the ORB's nitrate and is a period of fertilizer delivery from upland corn and soybean agriculture to streams. The harvest season from July to November carries 22% of the ORB's nitrate and is a time of nitrate retention on the landscape. We discuss nutrient management in the ORB including fertilizer efficiency, cover crops, and nitrate retention using constructed measures. 相似文献