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31.
The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency, in 3 sites of contrasted anthropic influence. The impact of the meteorological factors (temperature, relative humidity, rainfall, wind speed) was first estimated through principal component analysis, and then by stepwise multilinear regressions to include wind directions. The pollutants levels reflected the proximity of atmospheric emissions, in particular from a large industrial harbor. High humidity and mild temperatures, and in a lower extent low wind speed and rainfall, also favored higher concentration levels. The contributions of these meteorological aspects became minor when including wind direction, especially when approaching major emission sources. The bioaccumulation integration time towards meteorological variations was on a seasonal basis (1–2 months) but the wind direction and thus local emissions also relied on a longer time scale (12 months). This showed that the contribution of meteorological conditions may be prevalent in remote places, while secondary in polluted areas, and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons. In the same time, a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography. The resulting uncertainty, including sampling, preparation and analysis was below 30% when comfortable analytical conditions were achieved. Finally, the occurrence of unexpected events such as a major forest fire, permitted to evaluate that this type of short, although intense, events did not have a strong influence on PAH and metals bioaccumulation by lichen.  相似文献   
32.
The apparently unresolvable differences between managing national defense and local conservation, public recreation, and scientific research can be overcome through an advisory committee, with a strong and dedicated entity to drive the processes of governance and change. The case of the Garden Island Environmental Advisory Committee shows how the organizational and political difficulties of integrating state interests and federal concerns were met. Garden Island, off the coast of Perth, the capital of the State of Western Australia, is a base for the Royal Australian Navy which is administered by the federal Department of Defence. Examples are given of the committee's approach to integrated environmental management and the implementation of the Navy's environmental policy.  相似文献   
33.
针对国内外出现的整合质量管理体系 (QMS)、环境管理体系 (EMS)与职业安全卫生体系(OSHMS)的现状 ,笔者分析了当前整合的困难与存在的问题 ,进而提出了相应的改进措施。  相似文献   
34.
基于GIS和AI的地震灾害危险性分析与信息系统   总被引:4,自引:1,他引:4  
本文介绍了子课题“基于GIS和AI的地震灾害危险性分析与信息系统”的总体研究思路、1994年的进展以及今后的工作安排。在这一年之中,本课题进行了调研,了解了GIS技术的最新进展,总结了当前灾害研究的一些特点;对华北的一部分地区建立了试验性的地震构造信息系统,经过多种空间操作,产生了一系列新的数据集合;在矢量数据与栅格数据转换的基础上,提出了实用的网格单元特征的提取方法;初步研究了GIS与AI的结合途径。  相似文献   
35.
Recency preference of odour memory retrieval in honeybees   总被引:1,自引:0,他引:1  
Free-flying honeybees (Apis mellifera) were trained on tasks in which they had to choose one of three odours for a reward of sugar water. In acquisition, the bees learned this task in about five trials of training. Unrewarded retention tests showed that the odour memory was retained after 24-h delay. These findings are unsurprising. Integration experiments were then performed in which the bees had to learn two successive tasks of odour discrimination with conflicting demands. In task 1 (20 trials), one of three odours provided sugar water while the other two provided tap water. In task 2 (ten trials), which followed task 1 immediately, a different odour provided the reward. The bees were given unrewarded tests immediately after training on task 2 and then tested again after 10 min, 22 h or 24 h. The 22-h delay coincided with the circadian time for the start of task 1 training, while the 24 h coincided with the circadian time for the end of the task 2 training. Bees strongly preferred the rewarded odour for task 2 on immediate testing and after a 10-min delay. After delays of 22 and 24 h, they still preferred the rewarded odour for task 2. We conclude that the most recently acquired odour memory dominates behaviour in honeybees. The close association between floral odour and reward availability under natural circumstances may predispose honeybees to rely more on the most recently rewarded odour cue rather than on circadian time.  相似文献   
36.
旨在揭示油气产业集群竞争力形成机理,据此展开讨论。首先基于成熟的资源整合观RIBV(Resource and Integration-BasedView)和价值链理论在产业集群层面的拓展,通过融合形成集群资源价值链整合VBCRI(Value chain-Based Cluster ResourceIntegration)思想,表明产业集群资源以产业集群价值链为基本格架实施整合,从而培育产业集群竞争力;然后,从VBCRI出发,基于油气集群资源及其竞争力构成,以及油气集群资源价值链整合能力的分析,构建了油气产业集群竞争力形成机理概念模型,并运用结构方程模型,以我国油气产业为例加以验证。结果表明:基础资源、人力资源、社会关系资源均通过油气集群资源价值链整合(能力)的完全中介作用间接地对油气集群竞争力形成产生正向影响,资本资源则通过油气集群资源价值链整合(能力)的部分中介作用对油气集群竞争力形成产生影响,从而显示了油气集群资源价值链整合(能力)在油气产业集群资源作用于油气产业集群竞争力形成中的充分中介作用,揭示了油气产业集群竞争力形成机理。  相似文献   
37.
文章介绍了南京在青奥会环境保障方面的管控措施与取得的成效,认为南京青奥环境保障成功的关键在于高效畅通的运行机制、强力有效的控污手段、不遗余力的执法监管、紧密配合的区域联防、以及科技支撑的科学决策。最后,从构建南京都市圈生态环保一体化格局、实施重点片区工业布局优化调整、淘汰落后产能、建立环境执法高压严管长效机制等方面,提出了后青奥时代南京加强环境监管、改善环境质量的对策与建议。  相似文献   
38.
采用化学还原+重金属捕集+气浮过滤组合工艺处理重金属废水。结果表明:处理后的出水水质中重金属等各项指标均达到《污水综合排放标准》(GB8978—2002)所规定的一级水质排放标准,COD去除率达到40%以上,同时此工艺在工程实践中取得了最佳工艺参数,可为类似工程提供参考。  相似文献   
39.
Scientists assert that integrated research is a foundation of Sustainable Development. However, they often presume that differences between the bio-physical and social sciences are hurdles in the way of integration. We show that need not be the case. The problem lies in the way environmental research is organised. The essay goes on to discuss how the problem is being resolved, and the implications for ‘environmental science’.  相似文献   
40.
Achieving resource sustainability, particularly in the coastal zone, is complicated by a variety of interdependencies and trade-offs between economic, social, and ecological variables. Although trade-offs between each of these variables are important, this paper emphasizes the social components of resource management. In this regard a distinction is made between individual and cooperative choices. Individual choices frequently are made from a shortterm, self-interested perspective, whereas cooperative choices are made from a long-term, community and resource-sustainability perspective. Typically, when presented with a spectrum of resource management decisions, individuals have a tendency to act in a self-interested manner. Thus, cooperative benefits, such as reduced conflict and improved resource certainty, are not realized. An overview of selected aspects of social dilemma theory suggests that socially cooperative choice outcomes are attainable in coastal zone management by integrating structural and behavioral solutions in resource use decision making. Three barriers to successful integration of structural and behavioral solutions are identified as self-interest, mistrust, and variable perceptions of resource amenities. Examples from coastal zone management indicate that these barriers may be overcome using approaches such as scopereduction, co-management, community education, and local participation. The paper also provides comment on the potential benefits of integrating structural and behavioral solutions in international coastal zone management efforts.  相似文献   
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