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321.
Christine Wallgren 《Local Environment》2013,18(2):233-251
Abstract This study compares energy use for food transport to a farmers' market in Sweden with energy use for transport in the conventional food system. The farmers' market was investigated through data sampling from on-site investigations. The conventional food system was studied with the aid of life cycle assessments reported in the literature. Overall, the study found no significant differences in levels of energy use for transport to the farmers' market compared with the conventional food system. For certain products, such as fresh fruits and vegetables, transport-related energy use was much lower in the local system although the season in Sweden for this kind of product is restricted to two or three months at the end of the summer. However, there is considerable potential to increase energy efficiency in local food systems by organizing the selling in new ways and by using more energy efficient vehicles. 相似文献
322.
Sander Van Den Burg 《Local Environment》2013,18(4):367-381
This paper studies the emergence of one particular ‘new’ environmental policy instrument: disclosure of emission and pollution data. Disclosure is part of a relatively new sub‐set of regulatory measures, based on monitoring, transparency, citizen‐empowerment and accountability. It originated in the United States but has recently attracted international attention. The attractiveness of disclosure is obvious; it promises environmental improvement combined with strengthened environmental democracy and community empowerment. By analysing the experiences in the US, and the developments in the Netherlands, this paper seeks to assess the functioning and effectiveness of disclosure. The available empirical evidence suggests that disclosure has a positive impact on the environmental performance of industrial facilities as well as a democratising effect. It is argued that Dutch policy makers wrongfully assume that disclosure cannot work in the Netherlands. The consequence is that citizens are provided with little specific information that cannot be used to put pressure on polluters. 相似文献
323.
为了掌握南充市近年来城市空气质量变化及其达标情况,对南充市城区2008~2012年SO2、NO2和PM10的质量浓度数据进行统计分析,并计算各个站点的空气污染指数和空气质量指数。结果表明,3种污染物浓度值都有明显的下降趋势,S02浓度在0.002~0.052mg/m^3之间变化;N02浓度值从0.042mg/m^3下降到0.029mg/m^3;PM10浓度在0.060~0.063mg/m^3之间波动。南充市空气质量冬季较差,夏季较好。在5个监测点中,炼油厂空气质量最差,优良率为92.9%(85.1%);高坪空气质量最好,优良率为99.1%(98.3%)。相关性分析表明,南充市空气污染源主要是工业燃煤和机动车尾气。 相似文献
324.
J. Andrew Grant Dianne Balraj Georgia Mavropoulos‐Vagelis 《Natural resources forum》2013,37(4):269-279
International forestry governance is an integral part of the global policy debates on how to prevent deforestation, illicit extraction, and unsustainable timber practices. Africa is an important producer of timber, yet the region is beset by a lack of capacity and other governance challenges in the management of its forestry sector. We employ a network governance analysis to examine the extent to which the evolution and operation of the Forest Stewardship Council (FSC) and la Commission des Forêts d'Afrique Centrale (COMIFAC) have addressed governance challenges. We assess the strengths and weaknesses of these two leading examples of international forestry governance by introducing recent evidence and insights from Africa. We conclude with a policy‐relevant discussion of how the FSC and COMIFAC might enhance authority, legitimacy, and effectiveness and improve forestry governance in Africa and other parts of the world. 相似文献
325.
采用RT-PCR和RACE法,克隆得到斑鳢、鲢鱼CYPlA与斑鳢HSP70基因cDNA的核心序列,序列长度分别为908 bp、902 bp、684 bp,分别编码302、300、228个氨基酸;还克隆得到斑鳢、近江牡蛎GPX基因cDNA的部分序列,长度分别为720 bp、727 bp,分别编码119、232个氨基酸.多个重要养殖水生动物的去毒相关基因的成功克隆,为水产养殖动物去毒相关基因结构、功能、表达调控研究以及今后定向筛选高食用安全保障的水产品奠定基础. 相似文献
326.
Does copper reduce cadmium uptake by different rice genotypes? 总被引:4,自引:0,他引:4
A hydroponics experiment was conducted to investigate the effect of copper (Cu) on cadmium (Cd), calcium (Ca), iron (Fe), and zinc (Zn) uptake by several rice genotypes. The experiment was carried out as a 2×2×4 factorial with four rice genotypes and two levels of Cu and Cd in nutrient solution. Plants were grown in a growth chamber with controlled environment. The results showed a significant difference between the biomass of different rice genotypes (P 〈 0.001). The Cd and Cu concentration in the solution had no significant effect on the biomass. The addition of Cu significantly decreased Cd uptake by shoots and roots of rice (P 〈 0.001). The Cd concentration did not significantly influence Ca uptake by plants, whereas the Cu concentration did (P = 0.034). There was a significant influence of Cd on Fe uptake by shoots and roots (P 〈 0.001, P = 0.003, respectively). Zn uptake decreased significantly as the addition of Cd and Cu increased in shoots. We concluded that Cu had significant influence on Cd uptake. The possible mechanisms were discussed. 相似文献
327.
328.
329.
阐明了绿色食品的内涵,产生的历史背景、客观原因,以及发展绿色食品对保障食品安全性、解决农产品国际贸易壁垒,实现农业可续发展的重大意义。在回顾齐齐哈尔绿色食品产生发展历程,目前取得的成效及存在的主要问题基础上,提出了加快齐齐哈尔绿色食品产生发展的思路与对策,着重强调要注重保护和发送生态环境,加强生产为基地建设,建设为龙头企业、加强市场开拓等关键性问题。 相似文献
330.
We examine the control of air pollution caused by households burning wood for heating and cooking in the developing world. Since the problem is one of controlling emissions from nonpoint sources, regulations are likely to be directed at household choices of wood consumption and combustion technologies. Moreover, these choices are subtractions from, or contributions to, the pure public good of air quality. Consequently, the efficient policy design is not independent of the distribution of household income. Since it is unrealistic to assume that environmental authorities can make lump sum income transfers part of control policies, efficient control of air pollution caused by wood consumption entails a higher tax on wood consumption and a higher subsidy for more efficient combustion technologies for higher income households. Among other difficulties, implementing a policy to promote the adoption of cleaner combustion technologies must overcome the seemingly paradoxical result that efficient control calls for higher technology subsidies for higher income households. 相似文献