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991.
In May 2011, a highly mediatized direct action in the form of a “field liberation” took place in Flanders, Belgium, against a field trial of genetically modified potatoes. This direct action and its aftermath revealed the conflictual and antagonistic nature of the genetically modified organisms debate in Flanders. Consequently, it serves as a particularly suitable case to investigate the post-political thesis with regard to environmental discourse and politics. The aim of this paper is to investigate in what ways news media in their reporting contribute to processes of depoliticization and, resultantly, impede a democratic debate on the issues at stake. This paper attempts to provide an answer to this question based on a critical discourse analysis of the reporting by Flanders’ two generalist, elite newspapers, De Standaard and De Morgen and the alternative online news site DeWereldMorgen. The findings reveal the existence of three ideological cultures, which are characterized by different degrees of de/politicization. We conclude by discussing how this study adds to our understanding of the relation between the depoliticization of environmental discourse, democratic debate and twenty-first-century news media.  相似文献   
992.
Heavy metal soil contamination from mining and smelting has been reported in several regions around the world, and phytoextraction, using plants to accumulate risk elements in aboveground harvestable organs, is a useful method of substantially reducing this contamination. In our 3-year experiment, we tested the hypothesis that phytoextraction can be successful in local soil conditions without external fertilizer input. The phytoextraction efficiency of 15 high-yielding crop species was assessed in a field experiment performed at the Litavka River alluvium in the P?íbram region of Czechia. This area is heavily polluted by Cd, Zn, and Pb from smelter installations which also polluted the river water and flood sediments. Heavy metal concentrations were analyzed in the herbaceous plants’ aboveground and belowground biomass and in woody plants’ leaves and branches. The highest Cd and Zn mean concentrations in the aboveground biomass were recorded in Salix x fragilis L. (10.14 and 343 mg kg?1 in twigs and 16.74 and 1188 mg kg?1 in leaves, respectively). The heavy metal content in woody plants was significantly higher in leaves than in twigs. In addition, Malva verticillata L. had the highest Cd, Pb, and Zn concentrations in herbaceous species (6.26, 12.44, and 207 mg kg?1, respectively). The calculated heavy metal removal capacities in this study proved high phytoextraction efficiency in woody species; especially for Salix × fragilis L. In other tested plants, Sorghum bicolor L., Helianthus tuberosus L., Miscanthus sinensis Andersson, and Phalaris arundinacea L. species are also recommended for phytoextraction.  相似文献   
993.
Environmental Science and Pollution Research - Ethiopia and South Africa are among the few countries to still implement indoor residual spraying with dichloro-diphenyl-trichloroethane (DDT) for...  相似文献   
994.
Environmental Management - Growing recognition of the importance of wetlands to human and ecosystem well-being has led countries worldwide to implement wetland protection policies. Different...  相似文献   
995.
Many developing countries are currently undergoing increased industrialization, which has accelerated environmental degradation. This study aims to examine South Africa's industrial development path as a socio-economic strategy pursued along the rill-lines of sustainable industrial development (SID) in view of the post-1994 environmental legislative initiatives. An exploratory review guided the study analysis. As industrial development zones (IDZs), environmental sustainability research is virtually non-existent, leading to the poor understanding of this programme's role in SID. This study reveals that the government political commitment, 1996 South Africa's Constitution and National Environmental Act (No. 107 of 1998) are key pillars reconciling the environment and industrial development in diffusing apartheid legacies. Non-compliances re-occur in industries outside the IDZs due to shortage of environmental monitoring inspectors and government priorities changes. Therefore, there is need to ‘green’ IDZ stakeholders for proper environmental legislation implementation. Finally, the study highlights new potential directions for research into SID zoning.  相似文献   
996.
The distribution between hardened cement paste and cement pore water of selected concrete admixtures (BZMs), i.e., sulfonated naphthalene-formaldehyde condensate (NS), lignosulfonate (LS) and a gluconate-containing plasticiser used at the Paul Scherrer Institute for waste conditioning, was measured. Sorption data were fitted to a single-site Langmuir isotherm with affinity constants K=(19+/-4)dm(3)g(-1) for NS, K=(2.1+/-0.6) dm(3)g(-1) for LS and sorption capacities q=(81+/-16)g kg(-1) for NS, q=(43+/-8)g kg(-1) for LS. In the case of gluconate, a two-site Langmuir sorption model was necessary to fit the data satisfactorily. Sorption parameters for gluconate were K(1)=(2+/-1)x10(6)dm(3)mol(-1) and q(1)=(0.04+/-0.02)mol kg(-1) for the stronger binding site and K(2)=(2.6+/-1.1)x10(3)dm(3)mol(-1) and q(2)=(0.7+/-0.3)mol kg(-1) for the weaker binding site. Desorption of these BZMs from cement pastes and pore water in cement specimens prepared in the presence of the BZMs were then used to test the model. It was found that only minor parts of NS and LS could be mobilised as long as the cement composition was intact, whereas the sorption of gluconate was found to be reversible. The Langmuir model makes valuable predictions in the qualitative sense in that the pore water concentration of the BZMs is reduced by several orders of magnitude as compared to the initial concentrations. In view of the necessity for conservative predictions used in the safety analysis for disposal of radioactive waste, however, the predictions are unsatisfactory in that the measured pore water concentrations of NS and LS were considerably larger than the predicted values. This conclusion does not apply for gluconate, because its concentration in cement pore water was below the detection limit of approximately 50 nM.  相似文献   
997.
ABSTRACT

Recently developed models and data describing the interactions of gas-phase semi-volatile organic compounds with indoor surfaces are employed to examine the effects of sorption on nicotine's suitability as an environmental tobacco smoke (ETS) marker. Using parameters from our studies of nicotine sorption on carpet, painted wallboard, and stainless steel and previously published data on ETS particle deposition, the dynamic behavior of nicotine was modeled in two different indoor environments: a house and a stainless steel chamber. The results show that apparently contradictory observations of nicotine's behavior in indoor air can be understood by considering the effects of sorption under different experimental conditions. In indoor environments in which smoking has occurred regularly for an extended period, the sorbed mass of nicotine is very large relative to the mass emitted by a single cigarette. The importance of nicotine adsorption relative to ventilation as a gas-phase removal mechanism is reduced. Where smoking occurs less regularly or the indoor surfaces are cleaned prior to smoking (as in a laboratory chamber), nicotine deposition is more significant. Nicotine concentrations closely track the levels of other ETS constituents in environments with habitual smoking if the data are averaged over a period significantly longer than the period between cigarette combustion episodes. However, nicotine is not a suitable tracer for predicting ETS exposures at fine time scales or in settings where smoking occurs infrequently and irregularly.  相似文献   
998.
Wang GG  Van Lear DH  Hu H  Kapeluck PR 《Ambio》2012,41(3):284-291
Decaying root systems of harvested trees can be a significant component of belowground carbon storage, especially in intensively managed forests where harvest occurs repeatedly in relatively short rotations. Based on destructive sampling of root systems of harvested loblolly pine trees, we estimated that root systems contained about 32% (17.2 Mg ha−1) at the time of harvest, and about 13% (6.1 Mg ha−1) of the soil organic carbon 10 years later. Based on the published roundwood output data, we estimated belowground biomass at the time of harvest for loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina. We then calculated C that remained in the decomposing root systems in 2005 using the decay function developed for loblolly pine. Our calculations indicate that the amount of C stored in decaying roots of loblolly-shortleaf pine forests harvested between 1995 and 2005 in South Carolina was 7.1 Tg. Using a simple extrapolation method, we estimated 331.8 Tg C stored in the decomposing roots due to timber harvest from 1995 to 2005 in the conterminous USA. To fully account for the C stored in the decomposing roots of the US forests, future studies need (1) to quantify decay rates of coarse roots for major tree species in different regions, and (2) to develop a methodology that can determine C stock in decomposing roots resulting from natural mortality.  相似文献   
999.
With the objective to evaluate exposure of the population in Flanders (Belgium) to perfluorinated compounds (PFCs), we measured perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in settled dust in homes and offices, in a selection of food items from local origin, in drinking-water and in human serum. We complemented the data with results from a literature survey. Based on this dataset we calculated intake by children and adults from food, drinking-water, settled dust and soil, and air. Dietary exposure dominated overall intake. For adults, average dietary intake equalled 24.2 (P95 40.9) ng PFOS kg−1 d−1 and 6.1 (P95 9.6) ng PFOA kg−1 d−1, whereas for children the dietary intake was about 3 times higher. Predicted intake is high when compared to assessments in other countries, and to serum levels from Flanders, but comparable to the intakes published by The European Food Safety Authority (EFSA) in 2008. Intake of PFOS and PFOA remained below the Tolerable Daily Intake.  相似文献   
1000.
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