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51.
This public symposium explored ways to integrate knowledge about and strengthen cooperation on complex and interconnected global sustainability issues. (The symposium was organized by the United Nations University (UNU), The University of Tokyo Integrated Research System for Sustainability Science (IR3S), as well as UNESCO. Co-organizers were the Ministry of Education, Culture, Sports, Science and Technology-Japan (MEXT) and the Japan Society for the Promotion of Science (JSPS). Participants included representatives from key institutes and UNESCO’s programs in the areas of water, ocean and ecological sciences as well as social and natural sciences, UNESCO Member states, scholars and policymakers. The symposium program and list of speakers is attached. See also www.isp.unu.edu). The central question put to symposium deliberations was one that many policy- and decision-makers as well as academic scholars struggle with today: how can we overcome barriers to action that will put societies around the world on a path to a more stable and sustainable future? This article examines the presentations made during the symposium and draws upon them to explore opportunities for sustainability scientists to help meet this challenge. The paper is divided into three parts: Part I provides a brief introduction that places the symposium in context of current debates on sustainability science and discusses (a) the role of UNESCO and (b) the relevance of sustainability science to policy- and decision-making for sustainable development. Part II examines three steps that can be taken now to overcome barriers to sustainability and the role of sustainability science in each (a) building societal and environmental resilience; (b) increasing collaboration across geographical and disciplinary boundaries as well as between scientists and decision-makers; and (c) enhancing education for sustainable development (ESD). The paper concludes with a review of why these keys are essential and steps that can be taken in the future to facilitate their widespread application at multiple scales.  相似文献   
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Site index is an important forest inventory attribute that relates productivity and growth expectation of forests over time. In forest inventory programs, site index is used in conjunction with other forest inventory attributes (i.e., height, age) for the estimation of stand volume. In turn, stand volumes are used to estimate biomass (and biomass components) and enable conversion to carbon. In this research, we explore the implications and consequences of different estimates of site index on carbon stock characterization for a 2,500-ha Douglas-fir-dominated landscape located on Eastern Vancouver Island, British Columbia, Canada. We compared site index estimates from an existing forest inventory to estimates generated from a combination of forest inventory and light detection and ranging (LIDAR)-derived attributes and then examined the resultant differences in biomass estimates generated from a carbon budget model (Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3)). Significant differences were found between the original and LIDAR-derived site indices for all species types and for the resulting 5-m site classes (p?<?0.001). The LIDAR-derived site class was greater than the original site class for 42% of stands; however, 77% of stands were within ±1 site class of the original class. Differences in biomass estimates between the model scenarios were significant for both total stand biomass and biomass per hectare (p?<?0.001); differences for Douglas-fir-dominated stands (representing 85% of all stands) were not significant (p?=?0.288). Overall, the relationship between the two biomass estimates was strong (R 2?=?0.92, p?<?0.001), suggesting that in certain circumstances, LIDAR may have a role to play in site index estimation and biomass mapping.  相似文献   
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This study examined the effects of three widely used pesticides that have been previously detected in aquatic systems neighbouring agricultural fields on the early-life stages of the zebrafish Danio rerio. Tests involving single exposures and binary combinations of the s-triazine herbicides (atrazine and terbuthylazine) and the organophosphate insecticide chlorpyrifos were performed. Several endpoints, such as swimming behaviour, morphological abnormalities and mortality, were studied. In addition, the inhibition of acetylcholinesterase (AChE) activity was investigated in order to evaluate the mode of action and toxicity of chlorpyrifos in the presence of these herbicides. Results indicate that both binary mixtures elicited synergistic responses on the swimming behaviour of zebrafish larvae. Moreover, although the herbicides were not effective inhibitors of the AChE on their own, a synergistic inhibition of the enzyme activity was obtained by exposure to mixtures with chlorpyrifos. We observed a correlation between impairment of swimming behaviour of the larvae and inhibition of AChE activity. This study supports previous studies concerning the risk assessment of mixtures since the toxicity may be underestimated when looking only at the single toxicants and not their mixtures.  相似文献   
54.

Background, aim, and scope  

Alqueva Reservoir is the biggest artificial freshwater reservoir in Europe and is an important water supply for human and agricultural consumption in the Alentejo region (Portugal). Pollution can impair environmental and human health status, and to assure water quality and ecological balance, it is crucial to frequently monitor water supplies. In this study, we used an ecotoxicological test battery to identify the potential toxicity of water from this reservoir.  相似文献   
55.
Corbin JN 《Disasters》2008,32(2):316-335
This exploratory qualitative study considers the subjective resettlement experiences of children forced into armed conflict in Northern Uganda from the perspectives of 11 former child combatants and 11 adult community members. A thematic analysis was performed on the narrative data. The bioecological model was used to provide a conceptual framework for key themes. Major findings included the overarching impact of ongoing armed conflict on returnees' lives, the important role of the family in supporting children's resettlement, the harassment of former child soldiers by community members, and the community's inability to support systematically the returning children in tangible ways. This study recommends that humanitarian services at all levels strengthen the capacity of families to care for the material and psychoemotional needs of former child soldiers within their communities.  相似文献   
56.
This paper presents an evaluation of the cost-effectiveness of a novel passenger monitoring system based on RFID technology for implementation onboard passenger ships. Such a system will be able to detect and keep track of passengers onboard the ship in emergency situations in order to provide crucial decision support to the officer in charge of evacuation. This will lead to increased safety and security on passenger ships. However, this increased safety will come at a certain cost. A methodology in line with Formal Safety Assessment is employed in order to assess the cost-effectiveness of the system, involving a thorough risk analysis.  相似文献   
57.
Sovereign financial disaster risk management: The case of Mexico   总被引:1,自引:0,他引:1  
In 2006, Mexico became the first transition country to transfer part of its public-sector natural catastrophe risk to the international reinsurance and capital markets. The Mexican case is of considerable interest to highly exposed transition and developing countries, many of which are considering similar transactions. Risk financing instruments can assure governments of sufficient post-disaster capital to provide emergency response, disaster relief to the affected population and repair public infrastructure. The costs of financial instruments, however, can greatly exceed expected losses, and for this reason it is important to closely examine their benefits and alternatives. This paper analyzes the Mexican case from the perspective of the risk cedent (the Ministry of Finance and Public Credit), which was informed by analyses provided by the International Institute for Applied Systems Analysis (IIASA). The rationale for a government to insure its contingent liabilities is presented along with the fiscal, legal and institutional context of the Mexican transaction. Using publicly available data, the paper scrutinizes the choice the authorities faced between two different risk-transfer instruments: reinsurance and a catastrophe bond. Making use of IIASA's catastrophe simulation model (CATSIM), this financial risk management decision is analyzed within the context of a public investment decision.  相似文献   
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