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191.
In the period between 1999 and 2000 epiphytic bryophytes were taken as bioindicators for air pollution by use of the IAP method (Index of Atmospheric Purity) and the VDI method within the Association of Engineers standards list (adapted from guideline 3799, 1995) in the heavy industrialized town of Linz, Austria. 52 study sites (265 trees) were analysed regarding species richness, coverage, and vitality. Q-values (sensitivity factors), calculated for each species showed significant differences for the various host tree species. The results gained by the IAP and the VDI methods were diverse, regarding the various sites where only 25% were classified identical. These differences can mainly be attributed to the differing host tree species and the size of the recording area on the various trees. Clusters of similar pollution levels were calculated and drawn as maps for both methods tested. Comparing the results of the IAP and the VDI methods with data derived from technical measurements (SO2, NO, NO2, and dust) a correlation between IAP-indices and SO2 concentrations could be observed. No correlation was detected between the results derived from VDI recording and for NO, NO2, and dust.  相似文献   
192.
Galvanized or “chromium-plated” plastics are well known to the consumer from the automotive sector and sanitary area. Polymers such as acrylonitrile butadiene styrene (ABS) are typically coated with a layer system of chromium, nickel and copper to obtain the characteristic optical surface and resistance properties. Due to the complex manufacturing process and high quality requirements, the production of these plastic metal composites generates 10–30% of rejects. We, therefore, developed an innovative process cascade for the recovery of both components (metal and polymer) applying established technologies (mechanical pre-treatment, classification, melt filtration, CreaSolv® Process) and were able to obtain ABS regranulate having excellent properties regarding the characteristic values for strength but slight compromises in impact characteristics. Blends with different amounts of virgin ABS, virgin PC and recycled ABS material as well as the pure cases were successfully re-metallized, all of them passing adhesion test, thermal shock resistance and CASS test. The high purity of the recovered materials led to increased redemption prices for metal and polymer by a factor of 6 and 2.5, respectively. Thus, the value added of metallized plastic waste is maximized, revealing a highly positive economic prognosis of a commercial implementation of the developed process—even at moderate scale.  相似文献   
193.
Maintaining the provision of multiple forest ecosystem services requires to take into consideration forest sensitivity and adaptability to a changing environment. In this context, dynamic models are indispensable to assess the combined effects of management and climate change on forest dynamics. We evaluated the importance of implementing different approaches for simulating forest management in the climate-sensitive gap model ForClim and compared its outputs with forest inventory data at multiple sites across the European Alps. The model was then used to study forest dynamics in representative silver fir–European beech stands in the Dinaric Mountains (Slovenia) under current management and different climate scenarios. On average, ForClim accurately predicted the development of basal area and stem numbers, but the type of harvesting algorithm used and the information for stand initialization are key elements that must be defined carefully. Empirical harvesting functions that rigorously impose the number and size of stems to remove fail to reproduce stand dynamics when growth is just slightly under- or overestimated, and thus should be substituted by analytical thinning algorithms that are based on stochastic distribution functions. Long-term simulations revealed that both management and climate change negatively impact conifer growth and regeneration. Under current climate, most of the simulated stands were dominated by European beech at the end of the simulation (i.e., 2150 AD), due to the decline of silver fir and Norway spruce caused mainly by harvesting. This trend was amplified under climate change as growth of European beech was favored by higher temperatures, in contrast to drought-induced growth reductions in both conifers. This forest development scenario is highly undesired by local managers who aim at preserving conifers with high economic value. Overall, our results suggest that maintaining a considerable share of conifers in these forests may not be feasible under climate change, especially at lower elevations where foresters should consider alternative management strategies.  相似文献   
194.
There is a widespread consensus among sustainability experts about the need for ambitious transformative practices in order for a sustainable development to progress. Agenda 21 emphasised the need for multilevel and multi-actor governance and explicitly focused on the local level. The conceptual and analytical preference of governance beyond government has directed attention towards the interaction between state and non-state actors. The present article focuses on the role of (local) state institutions in sustainability governance. We argue that an effective implementation of sustainability in government institutions is a precondition for a successful multi-stakeholder governance of a sustainable development. The guiding question of this article is: How has sustainability been institutionalised in local governments in Germany in the last 20 years after Agenda 21 was adopted? Based on a conceptual framework, we are presenting the empirical results of a survey of 371 German cities and municipalities in this article, which primarily aims at providing empirical evidence on to what extent sustainability has been institutionalised in German local governments. The article ends with discussing the potential reasons for the institutionalisation deficit observed and gives an outlook on the potential for developing a sustainability state, that is, a state dedicated to institutionalising sustainability.  相似文献   
195.
This study aimed at cross-border mapping metal loads in mosses in eight European countries in 1990, 1995, and 2000 and at investigating confounding factors. Geostatistics was used for mapping, indicating high local variances but clear spatial autocorrelations. Inference statistics identified differences of metal concentrations in mosses on both sides of the national borders. However, geostatistical analyses did not ascertain discontinuities of metal concentrations in mosses at national borders due to sample analysis in different laboratories applying a range of analytical techniques. Applying Classification and Regression Trees (CART) to the German moss data as an example, the local variation in metal concentrations in mosses were proved to depend mostly on different moss species, potential local emission sources, canopy drip and precipitation.  相似文献   
196.
197.
In this study, the indicative value of mosses as biomonitors of atmospheric nitrogen (N) depositions and air concentrations on the one hand and site-specific and regional factors which explain best the total N concentration in mosses on the other hand were investigated for the first time at a European scale using correlation analyses. The analyses included data from mosses collected from 2781 sites across Europe within the framework of the European moss survey 2005/6, which was coordinated by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). Modelled atmospheric N deposition and air concentration data were calculated using the Unified EMEP Model of the European Monitoring and Evaluation Programme (EMEP) of the Convention on Long-range Transboundary Air Pollution (CLRTAP). The modelled deposition and concentration data encompass various N compounds. In order to assess the correlations between moss tissue total N concentrations and the chosen predictors, Spearman rank correlation analysis and Classification and Regression Trees (CART) were applied. The Spearman rank correlation analysis showed that the total N concentration in mosses and modelled N depositions and air concentrations are significantly correlated (0.53 ≤ rs ≤ 0.68, p < 0.001). Correlations with other predictors were lower than 0.55. The CART analysis indicated that the variation in the total N concentration in mosses was best explained by the variation in NH4+ concentrations in air, followed by NO2 concentrations in air, sampled moss species and total dry N deposition. The total N concentrations in mosses mirror land use-related atmospheric concentrations and depositions of N across Europe. In addition to already proven associations to measured N deposition on a local scale the study at hand gives a scientific prove on the association of N concentration in mosses and modelled deposition at the European scale.  相似文献   
198.
To categorize the marine environmental health status, the Oslo and Paris commissions have recently formulated Ecological Quality Objectives (EcoQOs) for many ecological features including the contamination of coastal bird eggs with mercury and organochlorines. In this study, we describe spatial and temporal patterns of egg contamination around the North Sea and compared them to the EcoQOs. Concentrations of mercury, polychlorinated biphenyl (??PCB) congeners, dichlorodiphenyltrichloroethane (??DDT) and derivatives, hexachlorobenzene (HCB) and hexachlorocyclohexane (??HCH) isomers were analysed in two tern species (Sterna hirundo and Sterna paradisaea) and Oystercatcher (Haematopus ostralegus) eggs collected between 2008 and 2010 in a total of 21 sites in seven countries surrounding the North Sea. Hg, ??PCB and HCB were highest in the southern sites, while ??DDT and ??HCH concentrations were greatest in eggs from the western North Sea and the Elbe estuary. There were rarely any consistent decreases over time for any compounds. In the terns, Hg, HCB and ??HCH increased at most sites, ??PCB and ??DDT in Sweden and Norway. In the Oystercatcher, HCB and ??HCH increased at more than the half of the sites, ??PCB, ??DDT and Hg at several German sites. In the terns, Hg, ??PCB and ??DDT exceeded the EcoQO in all, HCB in most years and sites. At most sites, ??HCH fulfilled the EcoQO in some study years. In the Oystercatcher, Hg, ??PCB and ??DDT exceeded the EcoQO in all or most years and sites. HCB and ??HCH fulfilled the EcoQO in some or all years at most sites. The EcoQO was exceeded most frequently in estuaries. We conclude that EcoQOs are suitable for drawing contamination patterns of the coastal North Sea in an easily understandable manner, offering the opportunity to harmonize the EcoQOs with coordinated environmental monitoring programmes.  相似文献   
199.
Eastern Mediterranean silvopastoral oak woodlands have been greatly damaged through forest conversion, illegal lumbering, overgrazing, and forest fires. The aim of this study was to assess land-use changes and the legacies that they have imprinted on the forest structure of Quercus macrolepis and accompanying Quercus pubescens and Quercus cerris woodlands on Lesvos Island, Greece. The size structures of adult oak populations were analyzed as indicators of long-term oak regeneration, while short-term recruitment was determined by counting oak seedlings and saplings. The size structure of the adult Q. macrolepis population was similar to the inverse J-shaped distribution typical for natural Mediterranean oak forests, indicating continuous recruitment with a constant mortality rate of mature individuals. Seedling and sapling densities were highly variable, but generally low in relation to adult oak densities. Recruitment of oak seedlings and saplings was positively related to determinants such as forest cover, adult oak density and basal area, woody plant richness, and litter cover. Both seedling and sapling occurrence were negatively associated with dung frequency, which suggests that sheep grazing imposes a barrier to oak recruitment. The study outlines a comprehensive land-use transition from the 1950 to 1970s, during which a complex and multifunctional agrosilvopastoral land-use system was simplified to an intensive grazing system. The discrepancy between the successful long-term regeneration and the less successful short-term recruitment of oaks illustrates that intensified livestock grazing has been a major driver of vegetation change. Grazing impact is likely to interact with increasing drought conditions, which may trigger a negative feedback cycle that undermines the capacity of woodlands to sustain ecosystem services.  相似文献   
200.
Background, Aim and Scope Perfluorooctane sulfonate (PFOS; C8F17SO3-) is a fully fluorinated organic compound which has been manufactured for decades and was used widely in industrial and commercial products. The recent toxicological knowledge of PFOS mainly concerns mono-substance exposures of PFOS to biological systems, leaving the potential interactive effects of PFOS with other compounds as an area where understanding is significantly lacking. However, a recent study, reported the potential of PFOS to enhance the toxicity of two compounds by increasing cell membrane permeability. This is of particular concern since PFOS has been reported to be widely distributed in the environment where contaminants are known to occur in complex mixtures. In this study, PFOS was evaluated alone and in combination with cyclophosphamide (CPP) to investigate whether a presence of PFOS leads to an increased genotoxic potential of CPP towards hamster lung V79 cells. Genotoxicity was investigated using the micronucleus (MN) assay according to the recent draft ISO/DIS 21427-2 method. PFOS alone demonstrated no genotoxicity up to a concentration of 12.5 mg/L. However, PFOS combined with two different concentrations of CPP, with metabolic activation, caused a significant increase in the number of micronucleated cells compared to treatments with CPP only. These results provide a first indication that PFOS has the potential to enhance the genotoxic action of CPP towards V79 cells, suggesting that together with the alterations in cell membrane properties shown previously, that genotoxicity of complex mixtures may be increased significantly by changes in chemical uptake. Together with an earlier study performed by the own working group it can be concluded that PFOS alone is not genotoxic in this bioassay using V79 cells up to 12.5 mg/L, but that further investigations are needed to assess the potential interaction between PFOS and other substances, in particular regarding the impact of membrane alterations on the uptake of toxic substances. Materials and Methods: - Results: - Discussion: - Conclusions: - Recommendations and Perspectives: -  相似文献   
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