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This study evaluates chemical trends of seven acidified reservoirs and 22 tributaries in the Erzgebirge from 1993 to 2003. About 85% of these waters showed significantly (p < 0.05) declining concentrations of protons (-69%), nitrate (-41%), sulfate (-27%), and reactive aluminum (-50% on average). This reversal is attributed to the intense reduction of industrial SO2 and NOx emissions from formerly high levels, which declined by 99% and 82% in the German-Czech border region between 1993 and 1999. The deposition rates of protons and sulfur decreased by 70-90%. Since 1993, the dry deposition of total inorganic nitrogen diminished to a minor degree, but the wet deposition remained unchanged. The surface waters reflect a substantial decrease in Al exchange processes, a release of sulfur previously stored in soils, and an uptake of nitrate by forest vegetation. The latter effect may be supported by soil protection liming which contributed to the chemical reversal in almost 20% of the study waters.  相似文献   
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The particle formation and growth events observed at a semirural background site in Denmark were analyzed based on particle number size distribution data collected during the period from February 2005 to December 2010. The new particle formation (NPF) events have been classified visually in detail according to 3D daily plots in combination with an automatic routine. A clear seasonal variation was found in the way that events occurred more frequently during the warm season from May to September and especially in June. The mean values of the apparent 6 nm particle formation rates, the growth rate and the condensation sink were about 0.36 cm?3 s?1, 2.6 nm h?1, 4.3?×?10?3 s?1, respectively. A positive relationship of oxidation capacity (OX?=?O3?+?NO2) of the atmosphere and the appearance of NPF events was found indicating that the oxidation of the atmosphere was linked to the formation of new particles. An analysis of a 3-day backward trajectories revealed that NW air masses from the North Sea were giving the highest probability of NPF events, namely between 20 and 40 %.  相似文献   
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Ziel und Hintergrund  

Seit Oktober 2003 liegt der Verordnungsentwurf zur Neuordnung der europ?ischen Chemikalienpolitik vor. Aus ihm ergeben sich zahlreiche, zum Teil neuartige Aufgaben für Hersteller und Importeure von Chemikalien, Zubereitungen und Erzeugnissen, für nachgeschaltete Anwender und für den Handel. Die Landesregierung Nordrhein-Westfalen hat in einem Pilotprojekt Schlüsselelemente des REACH-Systems in der Praxis erprobt. In dieser Ver?ffentlichung werden Erfahrungen aus dem Projekt aufgezeigt, die speziell für die Textilveredlung wichtig sind.  相似文献   
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Lack of technology and efficient management of solid waste coupled with poverty have motivated most developing countries to sort for cheap waste disposal methods with negative consequences on the environment. Open burning at waste dumps causes serious toxicological impacts. Most organic solid waste excluding plastics when burned cause considerably little environmental pollution. However, non-stoichiometric combustion of waste plastics produces significant amounts of various aliphatic and aromatic compounds, acidic gases, dust and smoke. These products pollute the air, water and soil generating significant health problems with related socioeconomic impacts on human, animals and plants. Some of these pollutants are toxic and/or carcinogenic, form acid-rain and influence climate change. Critical discourse and research on environmental toxicology resulting from air pollution with related health risk and impacts have been catalysed by the enactment of major environmental regulations and increased awareness. The new clean air act amendment of 1990 is estimated to require about $25billion annually for its implementation in the United States, indicating the gravity of the pollution problem. Understanding, controlling and mitigating the impacts of chemical pollution from multiple sources related to open burning of plastics is complex. This paper uses content analysis of relevant literature and field observations to analyse, evaluate and identify characteristic pollutants including their transmission potentials, sources and impacts on human health with the assessment, prevention and management of related risk. An affordable technology-based approach applied within a bottom-up management strategy to prevent and control pollution offers a sustainable solution underpinned by resource and energy recovery from waste.  相似文献   
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This article reports on the second Young Environmental Scientists Meeting that was hosted from 28 February to 2 March 2011 by the Institute for Environmental Research at RWTH Aachen University, Germany. This extraordinary meeting was again initiated and organized by the Student Advisory Council under the umbrella of Society of Environmental Toxicology and Chemistry Europe. A movie about the meeting and the abstracts of poster and platform presentations are freely available as supplemental material of this article.  相似文献   
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Indigenous people play an integral role in shaping natural environments, and the disruption to Indigenous land management practices has profound effects on the biosphere. Here, we use pollen, charcoal and dendrochronological analyses to demonstrate that the Australian landscape at the time of British invasion in the 18th century was a heavily constructed one—the product of millennia of active maintenance by Aboriginal Australians. Focusing on the Surrey Hills, Tasmania, our results reveal how the removal of Indigenous burning regimes following British invasion instigated a process of ecological succession and the encroachment of cool temperate rainforest (i.e. later-stage vegetation communities) into grasslands of conservation significance. This research provides empirical evidence to challenge the long-standing portrayal of Indigenous Australians as low-impact ‘hunter-gatherers’ and highlights the relevance and critical value of Indigenous fire management in this era of heightened bushfire risk and biodiversity loss.  相似文献   
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