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1.
Some important naturally occurring α- and β-radionuclides in drinking water samples collected in Italy were determined and the radiological quality evaluated. The mean activity concentrations (mBq L−1) of the radionuclides in the water samples were almost in the order: 26 ± 36 (234U) > 21 ± 30 (238U) > 8.9 ± 15 (226Ra) > 4.8 ± 6.3 (228Ra) > 4.0 ± 4.1 (210Pb) > 3.2 ± 3.7 (210Po) > 2.7 ± 1.2 (212Pb) > 1.4 ± 1.8 (224Ra) > 1.1 ± 1.3 (235U) > 0.26 ± 0.39 (228Th) > 0.0023 ± 0.0009 (230Th) > 0.0013 ± 0.0006 (232Th). The mean estimated dose (μSv yr−1) to an adult from the water intake was in this order: 2.8 ± 3.3 (210Po) > 2.4 ± 3.2 (228Ra) > 2.1 ± 2.1 (210Pb) > 1.8 ± 3.1 (226Ra) > 0.94 ± 1.30 (234U) > 0.70 ± 0.98 (238U) > 0.069 ± 0.087 (224Ra) > 0.036 ± 0.044 (235U) > 0.014 ± 0.021 (228Th) > 0.012 ± 0.005 (212Pb) > 0.00035 ± 0.00029 (230Th) > 0.00022 ± 0.00009 (232Th). It is obvious that 210Po, 228Ra, 210Pb and 226Ra are the most important dose contributors in the drinking water intake. As far as the seventeen brands of analysed drinking water were concerned, the committed effective doses were in the range of 2.81–38.5 μSv yr−1, all well below the reference level of the committed effective dose (100 μSv yr−1) recommended by the WHO. These data throw some light on the scale of the radiological impact on the public from some naturally occurring radionuclides in drinking water, and can also serve as a comparison for the dose contribution from artificial radionuclides released to the environment as a result of human practices. Based on the radionuclide composition in the analysed waters, comment was made on the new screening level for gross α activity in guidelines for drinking-water quality recommended by the WHO, 2004. 相似文献
2.
The objective of this study was to provide operational probability density functions (PDFs) for distribution coefficients (Kds) in freshwater, representing the partition of radionuclides between the particulate and the dissolved phases respectively. Accordingly, the Kd variability should be considered in uncertainty analysis of transport and risk assessment models. The construction of PDFs for 8 elements (Ag, Am, Co, Cs, I, Mn, Pu and Sr) was established according to the procedure already tested in Durrieu et al. [2006. A weighted bootstrap method for the determination of probability density functions of freshwater distribution coefficients (Kds) of Co, Cs, Sr and I radioisotopes. Chemosphere 65 (8), 1308–1320]: (i) construction of a comprehensive database where Kds values obtained under various environments and parametric conditions were collected; (ii) scoring procedure to account for the ‘quality’ of each datapoint (according to several criteria such as the presentation of data (e.g. raw data vs mean with or without replicates), contact time, pH, solid-to-liquid ratio, expert judgement) in the construction of the PDF; (iii) weighted bootstrapping procedure to build the PDFs, in order to give more importance to the most relevant datapoints. Two types of PDFs were constructed: (i) non-conditional, usable when no knowledge about the site of concern is available; (ii) conditional PDFs corresponding to a limited range of parameters such as pH or contact time; conditional PDFs can thus be used when some parametric information is known on the site under study. For 7 other radionuclides (Ba, Be, Ce, Ra, Ru, Sb and Th), a simplified procedure was adopted because of the scarcity of data: only non-conditional PDFs were built, without incorporating a scoring procedure. 相似文献
3.
New best estimates for the solid–liquid distribution coefficient (Kd) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The Kd best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil–radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide Kd are examined to complete the information derived from the best estimates with a rough prediction of Kd based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of Kd best estimates for a number of radionuclides, such as selenium, antimony, and iodine. 相似文献
4.
In his keynote address, Robert Cox raised key questions, many of which force us to consider the larger question of the role of academics in society. The authors respond by suggesting that environmental communication, like other communication studies, is inherently normative and that environmental communication scholarship is closely aligned to risk as a centerpiece to crisis analysis. The authors discuss the productive connections among science, communication and sound public policy that make society more fully functional, including the formation of effective public policy through science that is normative while seeking objectivity, evaluating and symbolizing motives in discourse, acknowledging uncertainty and acceptable uncertainty, and that material and symbolic dimensions of the environment are interdependent. Thus, such studies focus on the ethics of environment and must balance sound science and cultural considerations. 相似文献
5.
《Environmental Communication: A Journal of Nature and Culture》2013,7(1):110-118
Cape Farewell is the brainchild of London-based artist David Buckland. The project is centered round a series of sailing voyages into the Arctic, through routes that were previously icebound but are now passable. The expeditions take teams of world-renowned artists, educators, writers, musicians and thinkers into the Arctic, onboard a hundred-year old schooner, with the invitation to engage with scientists (from the National Oceanography Centre, as well as Southampton), to make art, and to draw people's attention to the effects of ocean currents on us and our climate. Since its first expedition in 2003, the project has grown to include educational programs, an award-winning website, a BBC documentary, and an exhibit, “The Ship, The Art of Climate Change,” developed with the Natural History Museum and which has embarked on a worldwide tour. In August 2007, Cape Farewell began a three-year residency at Southbank Centre, operating as a cultural eco-hub for the Centre's creative climate change initiatives, and has started a collaboration with the Eden Project in Cornwall, UK. This interview was conducted in the Cape Farewell offices, which are in David Buckland's studio atop his family home in Camden, London. Currently, Renée Lertzman is conducting a PhD in critical psychology studies at Cardiff University in Wales, UK. Her interviews and writings relating to environmental communication have appeared in The Sun Magazine, Orion, Land and People (Trust for Public Land), Speak Magazine, Terra Nova, and Organization & Environment. Lertzman can be contacted at http://www.reneelertzman.org. For more information about Cape Farewell, visit http://capefarewell.com. 相似文献
6.
Contaminant input into the environment can affect the biochemical responses of exposed organisms. Activity of conjugation enzymes, such as glutathione S-transferase (GST) has been proposed as a biomarker of susceptibility to the presence of potentially damaging xenobiotics. The aim of the present study was to evaluate the activity of total and Pi-class GST in the hepatopancreas of pink-shrimp Farfantepenaeus brasiliensis. The shrimp were caught at a single site at Concei??o Lagoon and transplanted to another site (Canto da Lagoa - CA) in the same lagoon, and to the laboratory (LAB), where they were kept for 15 days. This experiment was carried out in winter 2003 and in summer 2004. Shrimp were sampled before the exposure, at a zero time (t0), and after 15-days at CA site and LAB. The activity of total GST and Pi-isoform were analyzed using CDNB and ethacrynic acid (EA) as substrates, respectively. Shrimp caught in winter showed higher levels of Pi-class GST than those caught in summer, for both t0 and CA groups. Moreover, differences in the activity of this GST isoform between groups were observed only in winter, where the animals from t0 and CA groups presented higher activity when compared to those kept in the laboratory. This difference could be associated either to changes in the contaminant input or to other water quality parameters in this ecosystem. The elevated GST Pi activity observed in the shrimp of both t0 and CA groups sampled in winter could be related to salinity, since it was higher in winter than in summer. We could also suggest a possible association of this finding to a seasonal metabolic variation in this penaeid. If that is the case, one should take into account these alterations when considering the use of this GST isoform as biomarker in F. brasiliensis in environmental monitoring programs. 相似文献
7.
8.
Matthew R. Auer 《Sustainability Science》2007,2(2):179-187
It has been nearly 20 years since a working definition for “sustainable development” was put forward by the World Commission
on Environment and Development. The concept endures in the mission statements and frameworks of action of various societal
actors, including those of neighborhood associations, metropolitan development authorities, environmental ministries, and
United Nations (UN) specialized organizations, to name a few. Yet many observers doubt that sustainable development is occurring
in poor countries. This failure, the critics contend, stems from miserly transfers of foreign aid. The extent to which inadequate
aid is to blame for poor environmental/developmental outcomes is an open question. But vocal demands for increasing aid to
meet sustainable development goals come from many parts of society and are persistent. Exhortations for more aid to help poor
countries are noble, perhaps even justifiable, but there are understandable doubts about the wisdom of transferring large
capital and technical resources to countries that are slow to adopt needed institutional reforms. Aid without institutional
reform is a recipe for wasted resources and donor fatigue. Worse, it may enhance inequities of wealth and power in recipient
countries. There are few illustrations to draw on demonstrating how institutionally impoverished societies are affected when
they are compelled to absorb massive aid inputs over a short period––a remedy suggested by some prominent aid experts. As
a proxy, it is valuable to examine instances where swift macroeconomic changes, spurred by external investment and export-led
growth, has occurred without significant institutional development. The case of Equatorial Guinea and its sudden oil riches
is examined to discern whether, in the absence of meaningful institutional reform, rapid and profound increases in foreign
direct investment and export income enable poverty alleviation and sustainable development.
相似文献
Matthew R. AuerEmail: |
9.
This paper discusses the linkages between population change, land use, and deforestation in the Amazon regions of Brazil, Bolivia, Colombia, Ecuador, Perú, and Venezuela. We begin with a brief discussion of theories of population–environment linkages, and then focus on the case of deforestation in the PanAmazon. The core of the paper reviews available data on deforestation, population growth, migration and land use in order to see how well land cover change reflects demographic and agricultural change. The data indicate that population dynamics and net migration exhibit to deforestation in some states of the basin but not others. We then discuss other explanatory factors for deforestation, and find a close correspondence between land use and deforestation, which suggests that land use is loosely tied to demographic dynamics and mediates the influence of population on deforestation. We also consider national political economic contexts of Amazon change in the six countries, and find contrasting contexts, which also helps to explain the limited demographic-deforestation correspondence. The paper closes by noting general conclusions based on the data, topics in need of further research and recent policy proposals.Readers should send their comments on this paper to:
BhaskarNath@aol.com within 3 months of publication of this issue 相似文献
10.
《Environmental Communication: A Journal of Nature and Culture》2013,7(2):231-254
Place branding strategies play a significant role in the professional composition of landscape imagery, including the depiction of “natural” landscapes. In this paper, Brand Blue Mountains, a brand currently implemented in the Blue Mountains region (Australia), is discursively analyzed. The brand sets out an all-encompassing “Vision” defining the identity, values and personality of the World Heritage listed Blue Mountains landscape, summarized in the tagline Elevate Your Senses. This “vision” is visually translated into a strictly coordinated and copyrighted suite of logos, graphic design, color, fonts and various photographic styles. Analysis reveals that the degree of control that place brand strategists seek to exert over the visual expression of landscape identity is significant. A highly selective narrative of positive nature-based sensory experience is constructed through the holistic application of contemporary visual media. The brands' communications strategy naturalizes and reinforces a particular market-friendly version of place. The framework that brands set for the representation of landscapes overall amounts to an exercise in calculated aesthetics, whereby the form and content of landscape images of various kinds is measured to achieve the greatest market differentiation and impact which technologies allow. The result of this calculated aesthetic system, with its taglines, saturated color, careful composition and magazine-format brevity, is a reduction in the complexity of landscape representations and a perpetuation of nature stereotypes. 相似文献
11.
长江三角洲区域发展与人口,资源,环境 总被引:4,自引:0,他引:4
陈家其 《中国人口.资源与环境》1994,4(4):29-33
历史时期,长江三角洲地区经济发展,具有与人口增长基本同步的三个发展时期。在此过程中,人口增长因素,在不同历史时期,对区域发展起着各具特色的作用。南北朝以来,人口增长过快而产生一系列人口、资源、环境失衡问题,其中某些如水域环境变化等,对当今区域经济的发展,仍然起着深刻的作用与影响。当今随着经济的纵深发展,在历史问题基础上,深化产生了许多新问题,使人口、资源、环境关系更为复杂。对此必须抓住人口增长这个主要方面,挖掘资源潜力,统一规划,加强管理,使自然-社会-经济系统的各个方面处于最佳协调状态,控制熵增,以求区域环境的久治长安、区域经济的持续增长。 相似文献
12.
The distribution of some heavy metals in three different organs of mullet, Liza abu, and catfish, Silurus triostegus, from Atatürk Dam Lake located on Euphrates (Turkey) was studied. Co and Mo concentrations were below limits of detection in all fish organs, whereas Ni was also below limits in organs of mullet. The metal accumulation in the liver and gill of L. abu and S. triostegus was found to be quite high in comparison with the muscle. In general, the concentrations are similar to those previously observed on other fish studied in Atatürk Dam Lake and lower than those determined in Tigris River. The analysed metals (Co, Cu, Fe, Mn, Mo, Ni and Zn) were found in fish muscle at mean concentrations under the permissible limits proposed by FAO. 相似文献
13.
新的学术生长点:人口,资源,环境经济学研究 总被引:2,自引:0,他引:2
本文构造了人口、资源、环境关系的基本框架、认为:人口、资源、环境经济学研究是新的学术生长点,但目前还处在初级阶段。在方法论上,作者强调了系统方法的重要性,并提出了人口、资源、环境经济学研究值得关注的几个问题,譬如,资源环境的人口承载力问题,人口的活动方式,消费方式和生态意识问题,以及小区域的人口、资源和环境问题。 相似文献
14.
人口,资源,环境与发展系统研究的基本思路 总被引:1,自引:0,他引:1
叶小叶 《中国人口.资源与环境》1993,3(2):5-10
人口、资源、环境与发展问题相互关联,构成了一个复杂巨系统。应用系统科学的思想方法研究这个复杂巨系统,是当前最令人注目的重大学术领域。本文探讨了这一系统研究的范围框架、基本内容结构和研究方法,建立了针对我国实际问题的系统概念模型。这一概念模型首次把人口、资源、环境、经济、科技、教育、文化等基本要素组织在一个完整的社会核算体系中。 相似文献
15.
Benjamin A. Lyons Ariel Hasell Natalie Jomini Stroud 《Environmental Communication: A Journal of Nature and Culture》2018,12(7):876-894
Some extreme weather events may be more likely to affect climate change beliefs than others, in part because schema individuals possess for different events could vary in encouraging such links. Using a representative sample of U.S. adults and geocoded National Weather Service data, we examine how a range of extreme weather event categories relate to climate change beliefs, and the degree to which individuals’ self-reported experiences are shaped by their political views across event types. For tornado, hurricane, and flood events, we find no link with beliefs. For polar vortex and drought events, we find that although self-reported experience is linked with climate beliefs, reporting of these experiences is influenced by political identity and partisan news exposure. These findings underscore a limited role for extreme weather experiences in climate beliefs, and show that events more open to interpretation, such as droughts and polar vortex disturbances, are most likely to be seen through a partisan lens. 相似文献
16.
人类社会的城市化进程始终是与对水资源的开发利用同步的 ,水资源短缺将是制约城市发展的一道门槛。然而 ,在我国西部地区存在着严重的水资源短缺和难以利用的情况 ,无序的城市化又进一步恶化了本已极为严峻的水资源短缺。但城市化始终是实现西部开发的必然选择。因此 ,在实现西部大开发战略 ,推进城市化进程的过程中 ,必须通过严格控制中心城市规模 ,以控制对水资源的局部过度需求 ;通过进一步优化城镇体系布局 ,在推进城市化进程的同时 ,实现区域范围内水资源的供需平衡 ;通过对现有的城市产业结构加以调整 ,以提高水资源的利用效率。只有依靠这种适宜的城市化战略 ,才能在城市化进程中跨越水资源门槛 ,最终实现西部地区的可持续发展 相似文献
17.
世纪之交我国人口,资源,环境的趋势分析与对策 总被引:3,自引:1,他引:2
本文全面分析了我国人口、资源、环境的现状;及其在“九五”和2010年的发展趋势;并提出了促进我国经济建设与人口、资源、环境协调发展的对策和建议。 相似文献
18.
虞沈冠 《中国人口.资源与环境》1996,6(1):33-38
本文从区域可持续发展的角度,着重分析了搞土地批租给经济建设、农业生产和环境保护带来的利弊,指出土地批租具有经济发展上的进取性,资源利用上的合理性,环境治理上的主动性和社会发展的全面性,关键是要因势利导,加强管理,才能达到可持续发展的根本目的。 相似文献
19.
中国的人口,资源,环境问题及若干战略选择 总被引:3,自引:0,他引:3
王毅 《中国人口.资源与环境》1993,3(1):50-54
中国具有十分特殊的基本国情,如何根据中国的国情以及特定的历史与现实条件,选择适宜的组织机制,实施正确的长期发展战略,加速中国的现代化进程,这是一个十分紧迫而又令人关注的重大课题。本文主要从人口、资源、环境等方面分析中国现代化所面临的困境,以及应采取的战略选择。 相似文献