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101.
Systematic geochemical mapping based on sampling and analysis of surface soils (0–2 cm) has been carried out in several Norwegian cities. The soils in the oldest parts of the cities are contaminated with metals (especially Pb) and polycyclic aromatic hydrocarbons (PAH). Due to the fact that children are often in contact with surface soil, it was realized that special focus had to be directed towards soils in day-care centers and playgrounds. The first mapping and remedy program was initiated in Trondheim in 1996. Here, the importance of copper–chromium–arsenic (CCA)-pressure-impregnated wood in playing equipment as a pollution source for soils was documented, and a process was started with the aim to ban this product. Soils from day-care centers in the inner city of Bergen were polluted to a degree that required remediation in 45% out of 87 centers, mainly due to high concentrations of Pb and benzo(a)pyrene. In Oslo, 38% of 700 day-care centers needed remediation due to soil pollution by Pb, BaP, Cd, Hg, Ni and PCB. Removal of CCA-impregnated wood was necessary in more than half of the day-care centers The Norwegian parliament has decided to investigate all outdoor playing areas in day-care centers, playgrounds and schoolyards in Norway, starting in 2007 with day-care centers in the ten largest cities and five most important industrial areas. The Norwegian Institute of Public Health has developed quality criteria for soils in day-care centers and playgrounds for As, Cd, Cr6+, Hg, Ni, Pb, zinc, PAHsum16, benzo(a)pyrene, and PCBsum7. The Geological Survey of Norway has developed guidance for mapping of soil pollution (sampling, chemical analysis and reporting) in day-care centers. Especially the sampling strategy has been developed in the period 1996–2007, and the preferred sampling strategy is to collect at least 10 samples of surface soil (0–2 cm) from (1) “original soil” on the site, (2) artificial man-made “hills”, and (3) soils used for growing vegetables. A total number of 2,000 day-care-centres are to be investigated, and necessary remediation should be completed before the end of 2010.  相似文献   
102.
Industrial energy programs such as energy audit programs and long-term agreements (LTAs) are one of the most common means of promoting energy efficiency in industry. As a result of the European Energy End-Use Efficiency and Energy Services Directive from 2006, the Swedish Government Bill proposed a national energy program towards industrial small- and medium-sized enterprises (SMEs) using more than 500 MWh energy annually. The aim of this paper is to present the structure and design of the program, adopted in 2010, the logics in brief behind the structure, as well as an ex-ante evaluation of the program’s cost-effectiveness. The paper is aimed towards the part of the program involving industry, i.e. not the part involving companies within service and sales etc. The proposed design primarily includes a subsidized energy audit with some minor LTA-elements, such as the need to report results from the energy audit, to present a plan over which measures to conduct, and after three years present which measures that were implemented. The ex-ante evaluation of the program shows a cost-effectiveness of 0.25–0.50 Eurocents/kWh, yielding savings of about 700–1 400 GWh annually.  相似文献   
103.
We describe here a new type of method for isolation of rare cell populations in biological fluids. The method is based on the anthraquinone technology for covalent binding of molecules to a polymer surface. An anthraquinone molecule conjugated via a linker to an electrophilic group (AQ Immobilizer™ reagent, Exiqon A/S) is covalently bound to a polymer surface by UV irradiation. The electrophilic group of this AQ reagent can covalently bind a specific antibody directed against a specific cell marker. Applying a cell sample to the functional surface, the cells having the specific cell marker on the cell surface will bind to the antibody on the functional surface. Using this technique, even extremely small cell populations may be isolated. We succeeded in isolating fetal cells from maternal blood samples in the first trimester for chromosome defects genetic diagnosis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
104.
土地由中心到边缘呈现不同分布利用方式的村庄,构成了欧洲文化景观的基本单元.然而在许多的乡村景观中,那些拥有细致结构的耕地和有树木的草场的真正前工业时代的村庄正在不断失去其原有的结构,这种遗失威胁着文化的继承和生物多样性.因此,监测景观中这样的村庄真实形态的变化范围和速度是非常重要的.随着废弃时间的增加,村庄的真实形态不断丢失,我们所要研究的是怎样的丢失程度才能够通过卫星图像定量分析和目视解译进行评价.1999年,我们在波兰东南部的Bieszczady山脉开展本研究.使用1998年的陆地卫星TM数据,利用景观元素的粒度(田地大小)和土地覆盖组成(灌木和森林的扩侵)对代表真实村庄结构形态退化不同阶段的6种类型村庄进行定量描述.我们利用历史地图勾勒出村庄的边界,并测量从前森林和空地的范围.利用卫星数据,将当前的土地利用和表示成粒度及森林的扩侵状况的土地废弃程度绘制成图.退化沿着2条变化路径发生:被废弃并且最终变成森林,或者形成集约农业.为了验证这样的结果,我们通过对原始卫星影像的目视解译,将1000km2范围内的22个其他村庄分成了4类.而后,我们收集了过去60年人口变化的历史数据.村庄真实形态的分类与人口下降速度明显相关.我们希望验证和应用这种快速评估文化景观真实形态的方法能够得到重视,尤其是在随着欧盟的扩大正在经历或者将要发生巨大变化的欧洲区域.最后,我们论证了村庄具有成为一个融合自然与社会科学的景观尺度的可能性.  相似文献   
105.
由于受到众多因素大规模作用的影响,高纬度地区生态系统的变化异常活跃.这些地区的生态系统非常脆弱,各种全球变化过程都在影响着可更新林木资源持续生产和当地社会赖以生存的动植物资源丰度.本文对于北半球高纬度地区生态系统的一些新认识及其(所包含的)意义进行了讨论,并对提高生态系统的恢复力所采取的必要管理措施进行了探讨.认为在生态系统面临各种变化和干扰时系统管理的焦点应该从系统的恢复转移到系统功能的维系上来.生物多样性的作用是确保生态系统在经历干扰和重组时能够进行重组和发展,这一作用应该在系统管理与相关的方针政策中得到重视.强调应重新考虑现在的生态保护区的概念以发展一些动态的管理方法,使生态系统在面临环境变化时能够进行可持续的管理.而高纬度地区一些土著人习惯性的生态保护区的特点与那些对保护区进行动态保护的观点往往是一致的.针对高纬度地区动态景观中的生物多样性管理我们提出了新的发展方向,并从非传统的观点方面为其提供了经验例证.这些非传统的观点与看法可能会有助于提高生物多样性可持续管理和生态系统功能发挥的潜力.  相似文献   
106.
Environmental Science and Pollution Research - Little is known about biosecurity measures and toxic effects during pesticide application in the province of Jujuy, Argentina, particularly concerning...  相似文献   
107.
Predicted increases in runoff of terrestrial dissolved organic matter (DOM) and sea surface temperatures implicate substantial changes in energy fluxes of coastal marine ecosystems. Despite marine bacteria being critical drivers of marine carbon cycling, knowledge of compositional responses within bacterioplankton communities to such disturbances is strongly limited. Using 16S rRNA gene pyrosequencing, we examined bacterioplankton population dynamics in Baltic Sea mesocosms with treatments combining terrestrial DOM enrichment and increased temperature. Among the 200 most abundant taxa, 62 % either increased or decreased in relative abundance under changed environmental conditions. For example, SAR11 and SAR86 populations proliferated in combined increased terrestrial DOM/temperature mesocosms, while the hgcI and CL500-29 clades (Actinobacteria) decreased in the same mesocosms. Bacteroidetes increased in both control mesocosms and in the combined increased terrestrial DOM/temperature mesocosms. These results indicate considerable and differential responses among distinct bacterial populations to combined climate change effects, emphasizing the potential of such effects to induce shifts in ecosystem function and carbon cycling in the future Baltic Sea.  相似文献   
108.
Summary While considerable progress has been achieved in understanding and addressing environmental problems over the last 15 years, it is clear that much still remains to be done. Prominent among the concerns calling for further action are the dispersion of toxic substances from a large variety of sources and uses, the accumulating and widespread effects of air pollution, and inefficient management of the natural resource base needed to sustain future economic development. It is increasingly evident that work on these issues must be addressed in their global context, including the developing world.Mr Erik Lykke took up his duties as Director of Environment for the Organisation for Economic Co-operation and Development (OECD) on 5 November, 1984. He is Norwegian, and comes from the Norwegian Ministry of Environment, where he was appointed Director General when it was established in 1972. Before that appointment he held various posts in the Norwegian Ministry of Foreign Affairs and in the Norwegian Foreign Service, and worked in the Norwegian Embassies in Ottawa and London and the Delegation to NATO.Mr Lykke graduated from the University of Oslo in 1954 (MA in political science, history and sociology) and worked for a short time as a journalist. He was assistant to Mr. Trygve Lie (a former Secretary-General of the United Nations) and Foreign Minister Halvard Lange. He has worked on a number of national committees, dealing with space, nuclear research, research in science and technology, air, acid precipitation, and law of the sea and polar matters.From 1970, up to his appointment as OECD Director of Environment, he was closely involved in the development of Norwegian policy and practice on environmental protection and in international work in this field. He was actively engaged in the preparations for the 1972 UN Environment Conference and the 1972 Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft (he was the first Chairman of the Oslo Commission). He was also Chairman of the UN-ECE and OECD Environment Committees, and has led Norwegian delegations to a number of international meetings and conferences.The opinions expressed in this paper are those of the author and do not necessarily represent the views of the OECD or of the Governments of its Member countries.  相似文献   
109.
110.
This paper aims to identify the factors underlying farmers' propensity to participate in organic farming programmes in a Romanian rural region that confronts non-point source pollution. For this, we employ structural equation modelling with latent variables using a specific data set collected through an agri-environmental farm survey in 2001. The model includes one 'behavioural intention' latent variable ('propensity to participate in organic farming programmes') and five 'attitude' and 'socio-economic' latent variables ('socio-demographic characteristics', 'economic characteristics', 'agri-environmental information access', 'environmental risk perception' and 'general environmental concern'). The results indicate that, overall, the model has an adequate fit to the data. All loadings are statistically significant, supporting the theoretical basis for assignment of indicators for each latent variable. The significance tests for the structural model parameters show 'environmental risk perception' as the strongest determinant of farmers' propensity to participate in organic farming programmes.  相似文献   
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