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81.
Bernd Hanisch Bettina Abbas Werner Kratz Gerrit Schüürmann 《Environmental Sciences Europe》2004,16(4):223-238
Goal
In the Brandenburg State Office for the Environment an approach to assess the potential risk of drug residues in aquatic ecosystems has been developed based on an investigation of the consumption amounts in 1999 to identify or to exclude a potential environmental risk of important human drugs and further to define priority substances for monitoring programs in Brandenburg in the future.Method
This assessment approach tested with 60 drug agents is based on an exposure estimation considering the main path for the entry human—waste water—sewage plant—surface water, on a substance specific analysis of effects and on an analysis of the environmental fate as compartment distribution, bioaccumulation and persistence.Results
In Brandenburg surface waters the drug agent concentration for eight of the considered substances is supposed to be greater than 1 μg/l and for at least 13 of the considered substanoes the PNEC in aquatic ecosystems is assumed to be lower than 1 μg/l. A potential risk for the environment can be seen for the antibiotics Ciprofloxacin-HCl and Clarithromycin, the disinfectants Benzalkonium Chloride, Cocospropylendiaminguaniacetat, Glucoprotamine, Laurylpropylenediamine and Polyvidone-iodine, the sexual hormon Ethinylestradiol, the antidiabetic Metformin-HCl, the antiepileptic Carbamazepine and the lipid regulator Clofibrinic acid on the basis of effects because their PEC:PNEC-relation is about 1 or higher. For further 19 drug agents an environmental risk is to be assumed because of their environmental behaviour without support by ecotoxicological data at present.Conclusion
Although there is only a small base of valid ecotoxicological data, this risk assessment shows that adverse effects in the aquatic environment by some drug agents cannot be excluded. However, it should be noted that this first assessment gives only a crude orientation. Appropriate test data are necessary to refine the assessment in future. 相似文献82.
Bark samples of spruce, pine and oak trees were collected at two sites in southern Bavaria which are characterized by high agricultural ammonia emissions. The samples were taken using a recently developed bark sampling device which removes a defined layer of the bark. The bark was then analysed for ammonium concentration in order to reflect the environmental ammonia immission. The measured bark concentrations decreased with rising distance between the sample trees and the ammonia source. This applied (i) to measurements inside a closed forest stand ranging from forest edge with high immission to forest interior with much lower immission, and (ii) to the open field where single-standing trees were sampled. Comparing the ammonium concentrations among the three different tree species revealed significant correlations. Thus, it could be shown that old spruce trees are as usable for bark bio-monitoring as the traditionally used pine and oak trees. The ammonium concentrations of the bark were significantly correlated to measurements taken by ammonia passive samplers at the same locations. These results indicate that bark samples may be used for a standardised monitoring of airborne ammonia load. A major advantage of the technique is the determination of the long-term accumulative ammonia load using a single measurement. 相似文献
83.
Winfried Schröder Inga Hornsmann Roland Pesch Gunther Schmidt Stefan Fränzle Simone Wünschmann Heike Heidenreich Bernd Markert 《Environmental Sciences Europe》2008,20(1):62-74
Goal, Scope and Background
The study was conducted to test the hypothesis that the regional variability of nitrogen (N) and metal accumulations in terrestrial ecosystems are due to historical and recent ways of land use. To this end, in two regions of Central Europe the metal and N accumulations in both regions should be examined by comparative moss analysis. The regions should be of quantitatively specified representativity for selected ecological characteristics of Europe. Within both regions these characteristics should be covered by the sites where the moss samples were collected. The number of samples should allow for geostatistical estimation of the measured nitrogen and metal loads.Methods
The two regions of investigation were selected according to an ecological land classification of Europe which was computed by classification trees. Within each of both research areas the sampling points were localized according to the areas occupied by the ecologically defined land classes. The sampling and chemical analysis of mosses was conducted in accordance with an appropriate UNECE guideline by means of ICP-MS (metals) and combustion analysis (N). The quality of measurements was assured using certified reference materials. The differences of deposition loads were tested for statistical significance with regard to time and space. Variogram analysis was used to examine and model the spatial autocorrelation function of the measurements. Ordinary kriging was then applied for surface estimations.Results
By use of the ecological regionalisation of Europe the Weser-Ems Region (WER) and the Euro Region Nissa (ERN) were selected for investigation. The sampling sites represent quite well the natural landscapes and the land use categories of both regions. The measurement values corroborate the decline of metal accumulation observed since the beginning of the European Mosses Monitoring Survey in 1990. The metal loads of the mosses in the ERN exceed those in the WER significantly. The opposite holds true for the N concentrations: those in the WER are significantly higher than those in the ERN.Discussion
The decrease of heavy metal emissions is correlated with lowered deposition and accumulation rates in terrestrial ecosystems. The accumulation of nitrogen in the biosphere is not following this trend.Conclusions
The technique of moss analysis is adequate for spatially valid biomonitoring of spatial and temporal trends of metals and nitrogen in terrestrial ecosystems. By this, it enables to prove the efficiency of environmental policies.Recommendations and Perspectives
The accumulation of N in ecosystems is still a serious environmental problem. Related ecological impacts are the eutrophication of aquatic ecosystems like ground waters, lakes, rivers and oceans as well as the biocoenotic changes in terrestrial ecosystems. Thus, a statistically valid exposure analysis must encompass both, accumulation of metals and N bioaccumulation. Further, the bioaccumulation of persistent organic pollutants should be monitored. Finally, environmental biomonitoring should be conducted in much closer contact with human health aspects. 相似文献84.
Ionela Birloaga Vasile Coman Bernd Kopacek Francesco Vegliò 《Waste management (New York, N.Y.)》2014,34(12):2581-2586
This study refers to two chemical leaching systems for the base and precious metals extraction from waste printed circuit boards (WPCBs); sulfuric acid with hydrogen peroxide have been used for the first group of metals, meantime thiourea with the ferric ion in sulfuric acid medium were employed for the second one. The cementation process with zinc, copper and iron metal powders was attempted for solutions purification. The effects of hydrogen peroxide volume in rapport with sulfuric acid concentration and temperature were evaluated for oxidative leaching process. 2 M H2SO4 (98% w/v), 5% H2O2, 25 °C, 1/10 S/L ratio and 200 rpm were founded as optimal conditions for Cu extraction. Thiourea acid leaching process, performed on the solid filtrate obtained after three oxidative leaching steps, was carried out with 20 g/L of CS(NH2)2, 6 g/L of Fe3+, 0.5 M H2SO4, The cross-leaching method was applied by reusing of thiourea liquid suspension and immersing 5 g/L of this reagent for each other experiment material of leaching. This procedure has lead to the doubling and, respectively, tripling, of gold and silver concentrations into solution. These results reveal a very efficient, promising and environmental friendly method for WPCBs processing. 相似文献
85.
We introduce the notion that the energy of individuals can manifest as a higher‐level, collective construct. To this end, we conducted four independent studies to investigate the viability and importance of the collective energy construct as assessed by a new survey instrument—the productive energy measure (PEM). Study 1 (n = 2208) included exploratory and confirmatory factor analyses to explore the underlying factor structure of PEM. Study 2 (n = 660) cross‐validated the same factor structure in an independent sample. In study 3, we administered the PEM to more than 5000 employees from 145 departments located in five countries. Results from measurement invariance, statistical aggregation, convergent, and discriminant‐validity assessments offered additional support for the construct validity of PEM. In terms of predictive and incremental validity, the PEM was positively associated with three collective attitudes—units' commitment to goals, the organization, and overall satisfaction. In study 4, we explored the relationship between the productive energy of firms and their overall performance. Using data from 92 firms (n = 5939employees), we found a positive relationship between the PEM (aggregated to the firm level) and the performance of those firms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
86.
87.
88.
Ansgar Quinkenstein Jens Wöllecke Christian Böhm Holger Grünewald Dirk Freese Bernd Uwe Schneider Reinhard F. Hüttl 《Environmental Science & Policy》2009,12(8):1112-1121
Alley cropping is an agroforestry system that offers a promising land use alternative for the temperate zone. On the same field, the sustainable production of food and biomass is possible, while simultaneously, especially in marginal areas, the ecological function of the landscape can be improved. Thus, alley cropping corresponds with the increasing demand for renewable energy resources and for a specific adaptation to the predicted changes of climatic conditions within Central Europe.However, presently, little knowledge exists regarding the effects of alley cropping on the environment. In this study a literature survey was undertaken to provide an overview of the different ecological benefits arising from alley cropping systems within temperate Europe. Abiotic factors (nutrient cycle, microclimate), biotic factors (biodiversity) and the effects on the carbon cycle are discussed in detail.Summarising, the results showed that alley cropping may be an ecologically advantageous land use system for sustainable food and biomass production in comparison with conventional agricultural practices. As a very flexible, but low-input system, alley cropping can supply biomass resources in a sustainable way and at the same time provide ecological benefits. 相似文献
89.
Biomarkers are widely known to occur in the fossil record, but the unaltered biomolecules are rarely reported from sediments
older than Paleogene. Polar terpenoids, the natural products most resistant to degradation processes, were reported mainly
from the Tertiary conifers, and the oldest known are Cretaceous in age. In this paper, we report the occurrence of relatively
high concentrations of ferruginol derivatives and other polar diterpenoids, as well as their diagenetic products, in a conifer
wood Protopodocarpoxylon from the Middle Jurassic of Poland. Thus, the natural product terpenoids reported in this paper are definitely the oldest
polar biomolecules detected in geological samples. The extracted phenolic abietanes like ferruginol and its derivatives (6,7-dehydroferruginol,
sugiol, 11,14-dioxopisiferic acid) are produced only by distinct conifer families (Cupressaceae s. l., Podocarpaceae and Araucariaceae),
to which Protopodocarpoxylon could belong based on anatomical characteristics. Therefore, the natural product terpenoids are of great advantage in systematics
of fossil plant remains older than Paleogene and lacking suitable anatomical preservation. 相似文献
90.
Pang Swee Yun Suratman Suhaimi Latif Mohd Talib Khan Md Firoz Simoneit Bernd R. T. Mohd Tahir Norhayati 《Environmental science and pollution research international》2022,29(11):15849-15862
Environmental Science and Pollution Research - Surface sediments along the Southern Terengganu coast (≤7 km from the coast) were analyzed for polycyclic aromatic hydrocarbons (PAHs). The... 相似文献