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31.
Unprecedented global changes caused by human actions challenge society's ability to sustain the desirable features of our planet. This requires proactive management of change to foster both resilience (sustaining those attributes that are important to society in the face of change) and adaptation (developing new socioecological configurations that function effectively under new conditions). The Arctic may be one of the last remaining opportunities to plan for change in a spatially extensive region where many of the ancestral ecological and social processes and feedbacks are still intact. If the feasibility of this strategy can be demonstrated in the Arctic, our improved understanding of the dynamics of change can be applied to regions with greater human modification. Conditions may now be ideal to implement policies to manage Arctic change because recent studies provide the essential scientific understanding, appropriate international institutions are in place, and Arctic nations have the wealth to institute necessary changes, if they choose to do so.  相似文献   
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This article examines the role of building trust in Humanitarian Mine Action (HMA). The role of trust following a mine-clearance operation is largely an unexplored region. Drawing on case studies from Angola, Mozambique and Afghanistan, the article explores how trust can be understood in the context of humanitarian initiatives such as landmine clearance, and outlines the challenges associated with building trust among populations with experience of armed conflict. Because trust is difficult to re-establish following a war, the argument presented here suggests that one way in which this can be done is through building relationships at the organisational and interpersonal levels. The analysis reviews specific measures that mine-action agencies have used to build trust, looking at the strengths and weaknesses of different approaches. The analysis concludes by suggesting general guidelines for how mine-action practitioners can facilitate trust, and by outlining some promising avenues for future research.  相似文献   
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Kjell Grip 《Ambio》2017,46(4):413-427
Impressive numbers of global and regional governmental and non-governmental organizations are working in the field of the marine environment and its resources. Many of these organizations operate within international legal frameworks ranging from comprehensive global conventions, such as the United Nations Convention on the Law of the Sea to regional agreements aiming at protection and development of regional seas. Characteristic for the management of these seas, both at the national and international level, is that sectoral approaches predominate. Over time, several initiatives have been taken to improve cooperation, coordination and integration to achieve greater coherence of policies and strategies between different organizations dealing with marine and maritime management, within and outside the United Nation system. However, the success has been limited. The weaknesses of international organizations depend fundamentally on problems at the national level. The international organizations are no stronger than their Contracting Parties allow them to be.  相似文献   
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As a step toward better understanding the reactive Los Angeles air basin atmosphere, a study was undertaken at the University of California—Riverside Campus, to determine the composition and concentration of atmospheric particulate matter as a function of particle size and time. The study involved developing a method for obtaining size-classified, time-fractionated aerosol samples amenable to chemical and physical (including microscopic) analysis. During a 15-day period, samples were obtained over 4-hr periods and subsequently analyzed for nitrate, sulfate, iron, and lead. Concentration of six gaseous pollutantsj total aerosol light-scattering, and several meteorological measurements were simultaneously recorded and averaged over the 4-hr intervals. This data was presented graphically to show the diurnal variation in and relationship between gaseous, particulate, and meteorological measurements. A strong relationship between gaseous peroxyacetyl nitrate, particulate nitrate, and aerosol light-scattering was found. High concentrations of ammonium nitrate particles, mainly in the 0.5-2μ, diameter size range, were found in the atmospheric particulate samples collected on days of very high smog (very limited visibility).  相似文献   
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This paper describes the results of a study to determine the total mass and the mass distribution of atmospheric aerosols, especially that mass associated with particles greater than 10 μm diameter. This study also determined what fraction of the total aerosol mass a standard high-volume air sampler collects and what fraction and size interval settle out on a dust fall plate. A special aerosol sampling system was designed for this study to obtain representative samples of large airborne particles. A suburban sampling site was selected because no local point sources of aerosols existed nearby. Samples were collected under various conditions of wind velocity and direction to obtain measurements on different types of aerosols.

Study measurements show that atmospheric particulate matter has a bimodal mass distribution. Mass associated with large particles mainly ranged from 5 to 100 μm in size, while mass associated with small particles ranged from an estimated 0.03 to 5 μm in size. Combined, these two distributions produced a bimodal mass distribution with a minimum around 5 μm diameter. The high-volume air sampler was found to collect most of the total aerosol mass, not just that fraction normally considered suspended particulate. Dust fall plates did not provide a good or very useful measure of total aerosol mass. The two fundamental processes of aerosol formation, condensation and dispersion appear to account for the formation of a bimodal mass distribution in both natural and anthropogenic aerosols. Particle size distribution measurements frequently are in error because representative samples of large airborne particles are not obtained. Considering this descrepancy, air pollution regulations should specify or be based upon an upper particle size limit.  相似文献   
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Chapin FS  Danell K  Elmqvist T  Folke C  Fresco N 《Ambio》2007,36(7):528-533
Projected warming in Sweden and other Fennoscandian countries will probably increase growth rates of forest trees near their northern limits, increase the probability of new pest outbreaks, and foster northerly migration of both native and exotic species. The greatest challenges for sustainable forestry are to restore and enhance the ecological and socioeconomic diversity of intensively managed forested landscapes. With appropriate management, climate warming may facilitate the regeneration of this diversity. Experimental transplant gardens along latitudinal or altitudinal gradients and high-resolution maps of expected future climate could provide a scientific basis for predicting the climate response of potential migrant species. Management of corridors and assisted migration could speed the movement of appropriate species.  相似文献   
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