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131.
粮食生产系统中的镉:对敏感人群的健康威胁   总被引:1,自引:0,他引:1  
本文概述了瑞典农业系统中镉的状况以及镉的人类暴露状况.农业土壤(耕层)中的镉每年增加0.03%~0.05%.饲料是当地农业系统中镉增加的重要原因.当前暴露水平下已经有一些测量表明人体肾功能受到影响.如果粮食中的水平达到欧盟允许的最大限度,那么10%~25%的瑞典人群暴露的镉水平将超过暂时可容忍的每周摄入量(PTWI,7μg Cd/kg体重).人群中的敏感者是那些低铁状况(主要是女性)和肾紊乱的个体.最近的研究表明镉对骨质疏松症有影响,但还需要进一步的研究来辨别镉是否在早期发展阶段毒害神经.必须采取坚决行动来阻止农业土壤中镉含量进一步增加.本文给出了预防及采取措施的建议.  相似文献   
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133.
对食品供应链而言,有可能达到生态效率目标吗?有很多事情可以做,而且有很多既有利于环境也使各公司可赢利的"双赢"解决办法.本文给出一些实例,说明为了使一条更可持续的食品链成为可能所需要的变革/措施.近25年来,农业和食物产品加工业已经进行了大幅度结构调整,它表明在一段相当短的时期内可能再次发生广泛变革.  相似文献   
134.
ABSTRACT

Transparency in environmental governance is no longer an uncontroversial answer to problems of accountability and effectiveness. How to design effective transparency systems and in what policy contexts they are effective remain contested issues. This special section, consisting of this introduction and four research articles, interrogates complex and potentially conflicting links between transparency, accountability, empowerment and effectiveness in environmental governance. Building on existing literature and the four contributions, we discuss persisting diversity in varieties of transparency, the evolving dynamics of commodity chain transparency, and the consequences of emerging novel forms of digitalized transparency. As we show, the contributions to this special section interrogate in novel ways the transformative potential of transparency, through shedding light on the performative effects of transparency in ever more complex environmental governance contexts. These contexts may include, inter alia, the growing ubiquity of traceability in transnational commodity chains, the need for ever more anticipatory (ex-ante) forms of environmental governance, and an ever-broadening quest for digitally monitored environments. In particular, the impacts of the real-time ‘radical’ transparency engendered by use of novel digital technologies remain under-analyzed in the sustainability domain. We conclude by raising several critical concerns that deserve further scientific research and policy debate.  相似文献   
135.
Experience after the Chernobyl accident has shown that restoration strategies need to consider a wide range of different issues to ensure the long-term sustainability of large and varied contaminated areas. Thus, the criteria by which we evaluate countermeasures need to be extended from simple cost-benefit effectiveness and radiological protection standards to a more integrated, holistic approach, including social and ethical aspects. Within the STRATEGY project, the applicability of many countermeasures is being critically assessed using a wide range of criteria. Attention is being given to issues such as practicability, feasibility, capacity and environmental side-effects, as well as social factors such as public perceptions of risk, communication of information and the need for dialogue and consultation with affected communities, and ethical aspects such as informed consent and the fair distribution of costs and doses. Although such socio-ethical factors are now the subject of a substantial field of research, there has been little attempt to integrate them in a practical context for decision makers. Within this paper, we specifically consider the ethical aspects of restoration strategies and suggest practical means by which these can be taken into account in the decision making process, introducing a value matrix. The paper covers two critical areas: evaluation of individual countermeasures, and use of the matrix to ensure transparent and systematic consideration of values in selection of a restoration strategy.  相似文献   
136.
Phytoplankton concentration in Lake Kinneret (Israel) has varied up to 10-fold in space and time, with horizontal patches ranging from a couple of kilometres to a basin scale. Previous studies have used a 1D model to reproduce the temporal evolution of physical and biogeochemical variables in this lake. The question that arises then is how appropriate is a 1D approach to represent the dynamic of a spatially heterogeneous system, where there are non-linear dependencies between variables. Field data, a N-P-Z model coupled to both a 1D and a 3D hydrodynamic model, a 1D diffusion-reaction equation and scaling analysis are used to understand the role of spatial variability, expressed as phytoplankton patchiness, in the modelling of primary production. The analysis and results are used to investigate the effect of horizontal variability in the forcing and in the free mechanisms that affect the growth of patterns. The study shows that the use of averaged properties in a 1D approach may produce misleading results in the presence of localised patches, in terms of both concentration and composition of phytoplankton. The reason lies in the fact that the calibration process of ecological parameters in the 1D model appears to be site and process specific. That is, it depends on the pattern's characteristics and the underlying physical processes causing them. And this is a critical point for the success of numerical simulations under spatial variability. In this study, it is also shown that a length scale based on diffusion and growth rate of phytoplankton could be used as a criterion to assess the appropriateness of the 1D assumption.  相似文献   
137.
The recent rise of resilience thinking in climate security discourse and practice is examined and explained. Using the paradigmatic case of the United Kingdom, practitioners’ understandings of resilience are considered to show how these actors use a resilience lens to rearticulate earlier storylines of climate conflict in terms of complexity, decentralisation, and empowerment. Practitioners in the climate security field tend to reinterpret resilience in line with their established routines. As a result, climate resilience storylines and practices turn out to be much more diverse and messy than is suggested in the conceptual literature. Building on these findings, the recent success of resilience thinking in climate security discourse is explained. Climate resilience – not despite but due to its messiness – is able to bring together a wide range of actors, traditionally standing at opposite ends of the climate security debate. Through resilience storylines, climate security discourse becomes something to which a wide range of actors, ranging from security to the development field, can relate.  相似文献   
138.
Mycotoxins occurrence in wheat grains impose risks to human and animal health. The southern Brazil has favorable weather conditions for Fusarium graminearum infections and consequently for mycotoxins accumulation on grains. The goal of this study was to evaluate the behavior of new wheat commercial genotypes to Fusarium Head Blight (FHB), to control performance of new fungicide formulations and their relationship with mycotoxins concentration in grains. The manly mycotoxin occurrence on wheat grains in southern Brazil was deoxynivalenol (DON). Two cultivars showed high DON concentration above the tolerance limits (>3000 μg kg?1). Many other mycotoxins monitored presented concentrations below method detection limit. Satisfactory levels of fungicide effectiveness were achieved against F. graminearum. Some fungicides promoted a satisfactory decrease on DON accumulation in grains. The best results were obtained when prothioconazole was present. SDHI (Succinate dehydrogenase inhibitors) + QoI (Quinone outside inhibitors) fungicides showed benefic effects at FHB control at field, but it did not promote satisfactory reduction on DON contamination. Fungicides can be used satisfactory for FHB control and reduce DON contamination in grains in southern Brazil. The presence of prothioconazole should be recommended. Some genotypes showed high DON concentration and it was not directly related with FHB severity at field.  相似文献   
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140.

Background, aim, and scope  

The aim of the study was to identify the impact of polychlorinated dibenzo-p-dioxin and furan (PCDD/F) emission sources on ambient air concentrations in the Malopolska Region, southern Poland. Three sites were selected: the city center of Krakow (Aleje), an industrial area (Nova Huta), and a rural site (Zakopane). In order to investigate the annual variations of PCDD/F sources, summer and winter time samples were taken.  相似文献   
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