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121.
This special issue of Disasters on humanitarian governance focuses on risk and order. Its contributions show the tensions between humanitarian normative ideals and practical consequences, as many of the ordering effects are associated with either intended or unintended consequences. This introduction offers a conceptual framing of humanitarian governance. Defining humanitarian governance as a subset of global governance, the paper shows how humanitarians have attempted to improve the consequences of their work by fighting instrumentalisation and instituting rationalisation processes. It adapts four questions, originally formulated by Michael Barnett ( 2013 ), to examine the ways in which humanitarian governance functions in more detail: what kind of world is being imagined and produced through the specific concern with order and risk? Who governs? How is this a form of humanitarian governance and how is it organised? And finally, what are the principal techniques of such governance? The conclusion summarises the main findings and sets an agenda for further research.  相似文献   
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Regional Environmental Change - We develop and apply a synthetic framework for understanding potential adaptations to climate change in the Canadian agriculture sector through a case study of...  相似文献   
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Mutualistic relationships are ubiquitous in tropical coral reefs, but the costs and benefits to partner species are often poorly known. In Caribbean coral reefs, several species of snapping shrimp (Synalpheus spp.) dwell exclusively in marine sponges, which serve as both habitat and food source. A paired experimental design was used to examine the effects of Synalpheus occupancy on predation, morphology, and growth of their sponge host Lissodendoryx colombiensis in Bocas del Toro, Panama (9.351°N, 82.258°W) in June 2009. Shrimp occupancy significantly decreased consumption of sponges by a predatory sea star (Oreaster reticulatus) and also affected sponge morphology; sponges grown without shrimps decreased in canal size, in both the laboratory and the field. Shrimp occupancy had more ambiguous effects on sponge growth. In laboratory experiments, shrimp occupancy benefited sponge growth, although all sponges experienced overall decreases in mass. In field experiments, there were no significant differences in growth between occupied and empty sponges. However, the benefits of shrimp occupancy on sponge growth were negatively correlated with overall increases in sponge size; sponges that decreased in mass during the experiment benefited more from shrimp occupancy than sponges that increased in mass. These costs and benefits suggest that Synalpheus has variable effects on sponges: positive effects on sponges in the presence of predators, and/or when sponges are decreasing in mass (e.g., during periods of physical stress), but a negative effect on sponges during periods of active sponge growth.  相似文献   
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We examined trends in sea ice cover between 1979 and 2002 in four months (March, June, September, and November) for four large (approximately 100,000 km2) and 12 small (approximately 10,000 km2) regions of the western Arctic in habitats used by bowhead whales (Balaena mysticetus). Variation in open water with year was significant in all months except March, but interactions between region and year were not. Open water increased in both large and small regions, but trends were weak with least-squares regression accounting for < or =34% of the total variation. In large regions, positive trends in open water were strongest in September. Linear fits were poor, however, even in the East Siberian, Chukchi, and Beaufort seas, where basin-scale analyses have emphasized dramatic sea ice loss. Small regions also showed weak positive trends in open water and strong interannual variability. Open water increased consistently in five small regions where bowhead whales have been observed feeding or where oceanographic models predict prey entrainment, including: (1) June, along the northern Chukotka coast, near Wrangel Island, and along the Beaufort slope; (2) September, near Wrangel Island, the Barrow Arc, and the Chukchi Borderland; and (3) November, along the Barrow Arc. Conversely, there was very little consistent change in sea ice cover in four small regions considered winter refugia for bowhead whales in the northern Bering Sea, nor in two small regions that include the primary springtime migration corridor in the Chukchi Sea. The effects of sea ice cover on bowhead whale prey availability are unknown but can be modeled via production and advection pathways. Our conceptual model suggests that reductions in sea ice cover will increase prey availability along both pathways for this population. This analysis elucidates the variability inherent in the western Arctic marine ecosystem at scales relevant to bowhead whales and contrasts basin-scale depictions of extreme sea ice retreats, thinning, and wind-driven movements.  相似文献   
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Following the recommendations of the US National Academy of Sciences and the mandates of the 1987 Nuclear Waste Policy Amendments Act, the US Department of Energy has proposed Yucca Mountain, Nevada as the site of the world's first permanent repository for high-level nuclear waste. The main justification for permanent disposal (as opposed to above-ground storage) is that it guarantees safety by means of waste isolation. This essay argues, however, that considerations of equity (safer for whom?) undercut the safety rationale. The article surveys some prima facie arguments for equity in the distribution of radwaste risks and then evaluates four objections that are based, respectively, on practicality, compensation for risks, scepticism about duties to future generations, and the uranium criterion. The conclusion is that, at least under existing regulations and policies, permanent waste disposal is highly questionable, in part, because it fails to distribute risk equitably or to compensate, in full, for this inequity.  相似文献   
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Household fuel use in developing countries, particularly as biomass and coal, is a major source of carbonaceous aerosols and other air pollutants affecting health and climate. Using state-of-the-art emission inventories, a global three-dimensional photochemical tracer/transport model of the troposphere, and a global radiative transfer model based on methods presented in the latest IPCC Assessment Report (2007-AR4), we estimate the radiative forcing (RF) attributable to household fuel combustion in Asia in terms of current global annual-mean RF and future global integrated RF for a one-year pulse of emissions (2000) over two time horizons (100 and 20 years). Despite the significant emissions of black carbon (BC) aerosols, these estimates indicate that shorter-lived (non-Kyoto) air pollutants from household fuel use in the region overall seem to exert a small net negative RF because of the strong influence of reflective aerosols. There are, however, major uncertainties in emission estimates for solid fuel burning, and about the sustainability of household fuel wood harvesting in Asia (the carbon neutrality of harvesting). In addition, there is still substantial uncertainty associated with the BC radiative forcing. As a result we find that the sign of the RF from household biomass burning in the region cannot be established. While recognizing the value of integrating climate change and air pollution policies, we are concerned that for a ‘Kyoto style’ post-Kyoto treaty (with global cap-and-trade and the Global Warming Potential as the metric) expanding the basket of components with a selection of short-lived species without also including the wider range of co-emitted species may lead to unintended consequences for global-scale climate. Additional measurement, modelling, and policy research is urgently needed to reduce the uncertainties so that the net impact on climate of emissions and mitigation measures in this sector can be accurately assessed.  相似文献   
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