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451.
Since 1992, a boom of “sustainable development projects” has been registered in the Brazilian Amazon, turning it into a kind of open-air laboratory for sustainability. But their real impacts remain unclear, especially because of inadequate evaluation tools. A new device is therefore needed to unveil the inner mechanisms of development aid despite the difficulties linked with the diversity of contexts or the heterogeneity in the relevant parameters. Those are the challenges we met when we engaged in comparing the impacts of sustainable development programs in 13 sites throughout the Brazilian Amazon in order to identify determining factors of sustainability. To achieve our objective, we conceived an indicator system based on the results of intensive fieldwork, including social, economic, environmental, and biographical issues. Our results show that the most prominent problem of sustainability—evaluation of effectiveness—has not been tackled; life conditions and environmental preservation continue to appear antagonistic. At the same time, variability appears among outwardly coherent social groups, showing that a case-to-case approach is definitely indispensable and confirming the need to go “beyond panaceas” to find resolutions. This article successively addresses three points. First, we present the starting point of our research, or how the Amazon region was turned into a laboratory for sustainability and how our research project aimed at analyzing the consequences of this trend. Second, we discuss how available indicator systems fail to respond to the need for a multidimensional evaluation at the local level and, therefore, how we constituted our own analytical tool. Third, we focus on some results that can be derived from our system, especially in terms of identifying key factors needed to achieve sustainability in the Amazon.  相似文献   
452.
通过对输气站场常用的风险评估方法与RBI的技术方法进行对比分析,提出采用RBI技术对输气站场的分离器进行风险评估.根据输气站场分离器的失效机理和运行环境,对其失效概率和失效后果进行了定量分析,建立了输气站场分离器RBI风险评估流程.然后通过一个实际案例验证了基于RBI的风险评估方法在输气站场分离器风险评估中的合理性和实用性,并根据评估结果提出了分离器的优化检验策略.本研究为输气站场设备的风险评估提供了一种新的方法.  相似文献   
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Mu  Xiyan  Qi  Suzhen  Liu  Jia  Yuan  Lilai  Huang  Ying  Xue  Jiaying  Qian  Le  Wang  Chengju  Li  Yingren 《Environmental Chemistry Letters》2022,20(1):41-48
Environmental Chemistry Letters - Microplastics and bisphenol analogues are emerging environmental pollutants widely occurring in freshwaters. Harmful effects of microplastics and bisphenols have...  相似文献   
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Environmental Science and Pollution Research - We developed a new hybrid material resulting from an innovative supramolecular tripartite association between an ionic liquid covalently immobilized...  相似文献   
457.
Downstream and Coastal Impacts of Damming and Water Abstraction in Africa   总被引:1,自引:0,他引:1  
Anthropogenic factors associated with damming and water abstraction, and the resultant environmental pressures, are reviewed in six African river catchments using records and forecasts of climatic, demographic, and land-use change. Changes in the states of the flow regime through catchment drainage systems to the coastal sea are considered in conjunction with climate change and other human-induced pressures. The impacts of these changes on downstream and coastal environments and their communities are described in past, present, and future perspectives. Linkages between the issues and the pressures of damming and water abstraction are appraised and scientific, policy, and management responses proposed aimed at remedying existing and perceived future negative impacts. The study proposes that there is a need to integrate catchment and coastal management to account for the whole water flow regime together with its human dimensions. Management priorities relating to the operation of existing damming and abstraction schemes and planning of future schemes include the following: consideration of ways in which water discharges could be adjusted to provide improvements in downstream and coastal environmental and socioeconomic conditions; addressing the problem of sediment trapping impacting on the sustainability of dam reservoirs; and assessment of downstream and coastal impacts of future schemes in the light of climate change forecasts.  相似文献   
458.
Conservation management in Europe is often geared towards restoring semi-natural ecosystems, where the objective is to reverse succession and re-establish early-successional communities, to comply with national and international conservation targets. At the same time, it is increasingly recognised that ecosystems provide services that contribute to other, possibly conflicting policy requirements. Few attempts have been made to define these conflicts. Here, we assess some potential conflicts using a Calluna vulgaris-dominated moorland invaded by bracken (Pteridium aquilinum) as a model system, where the current policy is to reverse this process and restore moorland. We examined impacts of bracken control treatments on services (stocks and losses of C and mineral nutrients), litter turnover and biodiversity within a designed experiment over 7 years. Bracken litter was >2000 g m(-2) in untreated plots, and treatments reduced this quantity, and its element content, to varying degrees. Cutting twice per year was the most successful treatment in reducing bracken litter and its element content, increasing litter turnover, and increasing both mass and diversity of non-bracken vegetation. Diversity was greatest where bracken litter had been reduced, but species composition was also influenced by light sheep grazing. There was a significant loss of some chemical elements from bracken that could not be accounted for in other pools, and hence potentially lost from the system. In absolute terms large amounts of C and N were lost, but when expressed as a percentage of the total amount in the system, Mg was potentially more important with losses of almost a third of the Mg in the surface soil-vegetation system. There is, therefore, a potential dilemma between controlling a mid-successional invasive species for conservation policy objectives, especially when that species has evolved to sequester nutrients, and the negative effect of increasing environmental costs in terms of carbon accounting required, the potential input of nutrients to aquatic systems, and long-term nutrient loss. There is, therefore, a need to balance conservation goals against potential damage to biogeochemical structure and function.  相似文献   
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460.
人类遭大型食肉动物袭击有时会造成对食肉动物保护工作的强大的抵触情绪.我们回顾了在大型食肉动物保护工作中致力于解决人类安全问题的研究工作,并在我们所得到的如下几方面的调查结果的基础上,对有关遭袭击的频率和原因方面的陈述进行评估:①有关在世界不同地区遭大型食肉动物袭击次数的资料;②提供遭袭击细节的信息系统;③就遭遇大型食肉动物时如何应对的问题提出可靠建议的研究工作,目的是尽量减少遭袭击的可能性.我们的结论是,上述各标准中的现存信息很少,并且现有的信息往往不足以确定袭击的频率、袭击的原因以及如何避免上述袭击.我们建议为大型食肉动物保护工作建立信息系统(包括有关人类遭袭击和人类与食肉动物相遇的数据库),以便提供相关信息并满足将来对这些信息的需求.  相似文献   
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