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51.
Abdallah S  Heinzen R  Burnham G 《Disasters》2007,31(4):417-434
On 7 August 1998 truck bombs destroyed the US Embassies in Kenya and Tanzania.(1) The response in both countries was characterised by an absence of incident command, limited pre-hospital care, a disorganised hospital response and a lack of transportation for those injured. In the next five years USD 50 million was provided by the United States Agency for International Development (USAID) to alleviate the resulting suffering, support reconstruction and strengthen disaster preparedness capacity in the two countries. These two programmes have enhanced awareness of disaster management issues, improved training capacity, built response structures and provided material resources. Their design and implementation provide lessons for future disasters in developing countries. The assistance programmes evolved very differently. In Kenya the programme largely excluded the public sector and the potential for government coordination, while the Tanzanian programme concentrated heavily on central government and regional hospital structures-largely omitting the non-governmental or civil society sector. Excluding key stakeholders raises concerns about programme sustainability and the ability to respond effectively to future emergencies.  相似文献   
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Plants engage in multiple, simultaneous interactions with other species; some (enemies) reduce and others (mutualists) enhance plant performance. Moreover, effects of different species may not be independent of one another; for example, enemies may compete, reducing their negative impact on a plant. The magnitudes of positive and negative effects, as well as the frequency of interactive effects and whether they tend to enhance or depress plant performance, have never been comprehensively assessed across the many published studies on plant-enemy and plant-mutualist interactions. We performed a meta-analysis of experiments in which two enemies, two mutualists, or an enemy and a mutualist were manipulated factorially. Specifically, we performed a factorial meta-analysis using the log response ratio. We found that the magnitude of (negative) enemy effects was greater than that of (positive) mutualist effects in isolation, but in the presence of other species, the two effects were of comparable magnitude. Hence studies evaluating single-species effects of mutualists may underestimate the true effects found in natural settings, where multiple interactions are the norm and indirect effects are possible. Enemies did not on average influence the effects on plant performance of other enemies, nor did mutualists influence the effects of mutualists. However, these averages mask significant and large, but positive or negative, interactions in individual studies. In contrast, mutualists ameliorated the negative effects of enemies in a manner that benefited plants; this overall effect was driven by interactions between pathogens and belowground mutualists (bacteria and mycorrhizal fungi). The high frequency of significant interactive effects suggests a widespread potential for diffuse rather than pairwise coevolutionary interactions between plants and their enemies and mutualists. Pollinators and mycorrhizal fungi enhanced plant performance more than did bacterial mutualists. In the greenhouse (but not the field), pathogens reduced plant performance more than did herbivores, pathogens were more damaging to herbaceous than to woody plants, and herbivores were more damaging to crop than to non-crop plants (suggesting evolutionary change in plants or herbivores following crop domestication). We discuss how observed differences in effect size might be confounded with methodological differences among studies.  相似文献   
53.
Land use is rapidly expanding in the Greater Yellowstone Ecosystem, primarily from growth in the number of rural homes. There is a need to project possible future land use and assess impacts on nature reserves as a guide to future management. We assessed the potential biodiversity impacts of alternative future land use scenarios in the Greater Yellowstone Ecosystem. An existing regression-based simulation model was used to project three alternative scenarios of future rural home development. The spatial patterns of forecasted development were then compared to several biodiversity response variables that included cover types, species habitats, and biodiversity indices. We identified the four biodiversity responses most at risk of exurban development, designed growth management policies to protect these areas, and tested their effectiveness in two alternative future scenarios. We found that the measured biodiversity responses, including riparian habitat, elk winter range, migration corridors, and eight other land cover, habitat, and biodiversity indices, are likely to undergo substantial conversion (between 5% and 40%) to exurban development by 2020. Future habitat conversion to exurban development outside the region's nature reserves is likely to impact wildlife populations within the reserves. Existing growth management policies will provide minimal protection to biodiversity in this region. We identified specific growth management policies, including incentives to cluster future growth near towns, that can protect "at risk" habitat types without limiting overall growth in housing.  相似文献   
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A workshop was held in Berlin September 12–14th 2012 to assess the state of the science of the data supporting low dose effects and non-monotonic dose responses (“low dose hypothesis”) for chemicals with endocrine activity (endocrine disrupting chemicals or EDCs). This workshop consisted of lectures to present the current state of the science of EDC action and also the risk assessment process. These lectures were followed by breakout sessions to integrate scientists from various backgrounds to discuss in an open and unbiased manner the data supporting the “low dose hypothesis”. While no consensus was reached the robust discussions were helpful to inform both basic scientists and risk assessors on all the issues. There were a number of important ideas developed to help continue the discussion and improve communication over the next few years.  相似文献   
57.
Understanding the role of land use in urban stormwater quality management   总被引:12,自引:0,他引:12  
Urbanisation significantly impacts water environments with increased runoff and the degradation of water quality. The management of quantity impacts are straight forward, but quality impacts are far more complex. Current approaches to safeguard water quality are largely ineffective and guided by entrenched misconceptions with a primary focus on 'end-of-pipe' solutions. The outcomes of a research study presented in the paper, which investigated relationships between water quality and six different land uses offer practical guidance in the planning of future urban developments. In terms of safeguarding water quality, high-density residential development which results in a relatively smaller footprint would be the preferred option. The research study outcomes bring into question a number of fundamental concepts and misconceptions routinely accepted in stormwater quality management. The research findings confirmed the need to move beyond customary structural measures and identified the key role that urban planning can play in safeguarding urban water environments.  相似文献   
58.
Resource management issues continually change over time in response to coevolving social, economic, and ecological systems. Under these conditions adaptive management, or “learning by doing,” offers an opportunity for more proactive and collaborative approaches to resolving environmental problems. In turn, this will require the implementation of learning-based extension approaches alongside more traditional linear technology transfer approaches within the area of environmental extension. In this paper the Integrated Systems for Knowledge Management (ISKM) approach is presented to illustrate how such learning-based approaches can be used to help communities develop, apply, and refine technical information within a larger context of shared understanding. To outline how this works in practice, we use a case study involving pest management. Particular attention is paid to the issues that emerge as a result of multiple stakeholder involvement within environmental problem situations. Finally, the potential role of the Internet in supporting and disseminating the experience gained through ongoing adaptive management processes is examined.  相似文献   
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Air pollution has a deleterious impact on public health and the environment. There is few knowledge on the effect of air pollution on terrestrial microbial communities, despite the major role of microbes in ecosystems. Here, we designed an in situ trial ecosystem to assess the impact of moderate atmospheric pollution, below World Health Organization (WHO) thresholds, on an indigenous microbial communities, including bacteria, fungi, ciliates, algae, cyanobacteria, testate amoebae, rotifers and nematodes, extracted from terrestrial bryophytes. These micro-ecosystems were placed at a rural, an urban and an industrial site in France and were thus exposed to various levels of nitrogen dioxide (NO2), from 6.6–67.9 μg·m?3, and particulate matter, from 0.7–7.9 μg·m?3. Microbial analysis was performed by microscopy. We determined atmospheric temperature, relative humidity and particulate matter with diameter lower than 10 µm (PM10), Cu, Cr, Fe, Ni, Pb, Zn in PM10, and (NO2). Results show a significant impact of chronic moderate exposure to NO2 and copper Cu-associated particulate matter on the global microbial network complexity. This is evidenced by a loss of about 40 % of microbial co-occurrence links during incubation. Most lost microbial links are ecologically positive links. Moreover, most changes in community co-occurrence networks are related to testate amoebae, a major top predator of microbes. Overall, our findings demonstrate that air pollution can have strong deleterious effects on microbial interactions, even at levels below WHO thresholds.  相似文献   
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