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71.
Identifikation der kfz-bürtigen Schadstoffbelastung mit Hilfe der Verh?ltnisse der stabilen Isotope von Kohlenstoff und Schwefel 总被引:1,自引:0,他引:1
Tobias Türcke Stefan Norra Doris Stüben Zsolt Berner und Markus Leosson 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(3):127-133
Zusammenfassung Reifen-, Ru?-, Motoren?l-, Asphalt-, Plastik- und Lackproben aus dem Stra?enverkehr wurden auf ihre Kohlenstoff- und Schwefel-isotopenverh?ltnisse
mit dem Ziel untersucht, die Frage zu beant-worten, ob diese Isotopenverh?ltnisse als Indikatoren für die Belastungssituation
und die Schadstoffquellen bei der Untersuchung von stra?ennahen B?den eingesetzt werden k?nnen. Die δ11C-Werte der technischen Substrate lagen zwischen-30‰ und-18‰ relativ zum PDB-Standard, Dabei zeigte sich aufgrund der unterschiedlichen
Herstellungsverfahren eine deutliche Abgrenzung der Substrate untereinander. Asphalt hatte Werte zwischen-23 und-18‰, Ru?
zwischen -27 und -22‰ Die Ru?proben unterschieden sich je nach Art des verwendeten Kraftstoffs. Plastik, Lack und Motor?le
zeigten ?hnliche δ13C-Werte, die zwischen-30 und-27‰ lagen. Reifen haben relativ konstante δ13C-Werte um -26‰ Der Einflu? des Stra?enverkehrs auf die δ13C-Werte im Stra?ensediment und in stra?ennahen B?den konnte anhand verschiedener Kohlenstoffspezies an einem Transekt an einer
Landstra?e aufgezeigt werden. Ein Vergleich mit verkehrstypischen Schwermetallemissionen ergab bei einzelnen Kohlenstoffspezies
einen ?hnlichen Verlauf der Schwermetallkonzentrationen und der δ13C-Werte.
Die δ34S-Werte lagen zwischen -6 und +8‰ relativ zum CDT-Standard. Eine Abgrenzung der Substrate in ihren δ14S-Werten war hierbei nicht m?glich.
相似文献
72.
Shiping Gong Melita Vamberger Markus Auer Peter Praschag Uwe Fritz 《Die Naturwissenschaften》2018,105(5-6):34
Chinese softshell turtles (Pelodiscus spp.) are widely distributed, ranging from the Amur and Ussuri Rivers in the Russian Far East through the Korean Peninsula, Japan, and eastern, central, and southern China to southern Vietnam. In East and Southeast Asia, Chinese softshell turtles are traditionally exploited for food and have been farm-bred in China since the Spring and Autumn Period, more than 2400 years ago. Currently, the annual production of Pelodiscus amounts to 340,000 t in China alone. Using mitochondrial DNA (2428 bp) and five nuclear loci (3704 bp), we examined broad sampling of wild and farm-bred Pelodiscus to infer genetic and taxonomic differentiation. We discovered four previously unknown mitochondrial lineages, all from China. One lineage from Jiangxi is deeply divergent and sister to the mitochondrial lineage of Pelodiscus axenaria. The nuclear loci supported species status for P. axenaria and the new lineage from Jiangxi. Pelodiscus maackii and P. parviformis, both harboring distinct mitochondrial lineages, were not differentiated from P. sinensis in the studied nuclear markers. The same is true for two new mitochondrial lineages from Zhejiang, China, represented by only one individual each, and another new lineage from Anhui, Guangdong, Jiangxi and Zhejiang, China. However, Vietnamese turtles yielding a mitochondrial lineage clustering within P. sinensis were distinct in nuclear markers, suggesting that these populations could represent another unknown species with introgressed mitochondria. Its species status is also supported by the syntopic occurrence with P. sinensis in northern Vietnam and by morphology. In addition, we confirmed sympatry of P. axenaria and P. parviformis in Guangxi, China, and found evidence for sympatry of P. sinensis and the new putative species from Jiangxi, China. We also discovered evidence for hybridization in turtle farms and for the occurrence of alien lineages in the wild (Zhejiang, China), highlighting the risk of genetic pollution of native stock. In the face of the large-scale breeding of Pelodiscus, we claim that the long-term survival of distinct genetic lineages and species can only be assured when an upscale market segment for pure-bred softshell turtles is established, making the breeding of pure lineages lucrative for turtle farms. Our findings underline that the diversity of Pelodiscus is currently underestimated and threatened by anthropogenic admixture. We recommend mass screening of genetic and morphological variation of Chinese softshell turtles as a first step to understand and preserve their diversity. 相似文献
73.
Ralf Schulz Maike Hauschild Markus Ebeling Jakob Nanko-Drees Joem Wogram Mathias Liess 《Chemosphere》1998,36(15):3071-3082
A field method is described, which allows the qualitative estimation of pesticide contamination in the edgeof-field runoff. The method employs cheap and easy-to-use runoff sampling bottles, which were installed in an agricultural stream catchment over a period of three growing seasons. During this time 18 runoff events were detected, in nine of which insecticide contamination was measured (maximum concentrations: lindane 0.7 μg l−1 and 12.7 μg kg−1, parathion 20 μg l−1 and 728 μg kg−, fenvalerate 18.4 μg 1-1 and 924 μg kg−1). These insecticides were detected mainly as particle-bound chemicals. On about 80 % of the occasions the presence or absence of runoff measured in the field was in agreement with a simulation of runoff presence or absence using the runoff model KINEROS. 相似文献
74.
Tobias Türcke Stefan Norra Doris Stüben Zsolt Berner Markus Leosson 《Environmental Sciences Europe》1999,11(3):127-133
Different sources of traffic immissions (tyres, soot, oil, asphalt, plastic, paint) were analysed for stable carbon and sulphur isotope ratios. The aim of this study is to investigate whether these isotope ratios can be used to evaluate the environmental impact of traffic immitted harmful substances in roadside soils. The δ13C values of technical materials are between -30‰ and -18‰ (PDB). They can be distinguished by their δ13C value because of specific production methods. The δ13C value of asphalt is between -23 and -18‰, soot shows values from -27 to-22‰ Moreover, soot of different fuel have different carbon isotope ratios. Plastic, paint and oil have similar δ13C from -30 to -27‰ Carbon isotope ratios of automobile tyres are around -26‰ Traffic impact on the carbon isotope composition is reflected in δ13C values of various carbon spezies found in street sediments and road side soils. These δ13C values correlate to concentrations of lead and platinum. Although δ34S values of technical materials are between -6 and +8‰ it was not possible to characterise samples according to their Sulphur isotopic compostion. 相似文献
75.
Ozone measurements along vertical transects in the Alps 总被引:1,自引:1,他引:0
Herbert Werner Manfred Kirchner Gerhard Welzl Markus Hangartner 《Environmental science and pollution research international》1999,6(2):83-87
To investigate the vertical profiles of air pollutants in the boundary layer, aircraft and balloon-born measurements and measurements
using a cable car as an instrument platform have been performed in different parts of the Alps. This on-line monitoring of
atmospheric pollutants requires expensive and sophisticated techniques. In order to control ambient air quality in remote
regions, where no infrastructure like power supply is available, simple instruments are required. The objective of this study,
which was coordinated and evaluated by the GSF-Forschungszentrum für Umwelt und Gesundheit was first, to investigate the vertical
distribution of ozone in different parts of the Alps and secondly, in addition to continuous analyser measurements, to test
monitoring by means of two types of passive samplers. The selection of these samplers — one for one week use and another one
for two week application — was based on a passive sampler intercomparison done in a preliminary study one year earlier. 相似文献
76.
A newly developed agent-based framework for modeling, simulation, and evaluation of resource management in self-sustainable human settlements is presented, along with the ability of the framework to prolong the self-sustainability of the observed human settlement system in the simulation environment. In this study the focus is on the analysis of a conducted water management simulation based on observations of an existing eco-village in Croatia, in the context of producing, storing, and consuming water as a resource. The conducted research shows that the developed framework was able to prolong the self-sustainability of localized water production, storage, and consumption dynamics when managing the water allocation with the use of self-sustainability mechanisms, in comparison to water management without using such mechanisms, under the same initial conditions. The work is placed within the context of sustainable development, Internet of Things, as well as Environmental Internet of Things areas of research, analyzing the ambiguous relationship between the terms ‘sustainable development’ and ‘self-sustainability’. 相似文献
77.
Yan GUO Chuanfu WU Qunhui WANG Min YANG Qiqi HUANG Markus MAGEP Tianlong ZHENG 《Frontiers of Environmental Science & Engineering》2016,10(4):6
The use of PLA/starch blends for nitrogen removal was achieved.
The influence of different operating parameters on responses was verified using RSM.
The conditions for desired responses were successfully optimized simultaneously.
Blends material may have a promising application prospect in the future.
Nitrogen removal from ammonium-containing wastewater was conducted using polylactic acid (PLA)/starch blends as carbon source and carrier for functional bacteria. The exclusive and interactive influences of operating parameters (i.e., temperature, pH, stirring rate, and PLA-to-starch ratio (PLA proportion)) on nitrification (Y1), denitrification (Y2), and COD release rates (Y3) were investigated through response surface methodology. Experimental results indicated that nitrogen removal could be successfully achieved in the PLA/starch blends through simultaneous nitrification and denitrification. The carbon release rate of the blends was controllable. The sensitivity of Y1, Y2, and Y3 to different operating parameters also differed. The sequence for each response was as follows: for Y1, pH>stirring rate>PLA proportion>temperature; for Y2, pH>PLA proportion>temperature>stirring rate; and for Y3, stirring rate>pH>PLA proportion>temperature. In this study, the following optimum conditions were observed: temperature, 32.0°C; pH 7.7; stirring rate, 200.0 r·min-1; and PLA proportion, 0.4. Under these conditions, Y1, Y2, and Y3 were 134.0 μg-N·g-blend-1·h-1, 160.9 μg-N·g-blend-1·h-1, and 7.6 × 103 μg-O·g-blend-1·h-1, respectively. These results suggested that the PLA/starch blends may be an ideal packing material for nitrogen removal. 相似文献
78.
Jamie N. Womble Gail M. Blundell Scott M. Gende Markus Horning Michael F. Sigler David J. Csepp 《Marine Biology》2014,161(6):1361-1374
Foraging theory predicts that animals will adjust their foraging behavior in order to maximize net energy intake and that trade-offs may exist that can influence their behavior. Although substantial advances have been made with respect to the foraging ecology of large marine predators, there is still a limited understanding of how predators respond to temporal and spatial variability in prey resources, primarily due to a lack of empirical studies that quantify foraging and diving behavior concurrently with characteristics of prey fields. Such information is important because changes in prey availability can influence the foraging success and ultimately fitness of marine predators. We assessed the diving behavior of juvenile female harbor seals (Phoca vitulina richardii) and prey fields near glacial ice and terrestrial haulout sites in Glacier Bay (58°40′N, ?136°05′W), Alaska. Harbor seals captured at glacial ice sites dived deeper, had longer dive durations, lower percent bottom time, and generally traveled further to forage. The increased diving effort for seals from the glacial ice site corresponded to lower prey densities and prey at deeper depths at the glacial ice site. In contrast, seals captured at terrestrial sites dived shallower, had shorter dive durations, higher percent bottom time, and traveled shorter distances to access foraging areas with much higher prey densities at shallower depths. The increased diving effort for seals from glacial ice sites suggests that the lower relative availability of prey may be offset by other factors, such as the stability of the glacial ice as a resting platform and as a refuge from predation. We provide evidence of differences in prey accessibility for seals associated with glacial ice and terrestrial habitats and suggest that seals may balance trade-offs between the costs and benefits of using these habitats. 相似文献
79.
We investigate the effect of buoyancy on the small-scale aspects of turbulent entrainment by performing direct numerical simulation of a gravity current and a wall jet. In both flows, we detect the turbulent/nonturbulent interface separating turbulent from irrotational ambient flow regions using a range of enstrophy iso-levels spanning many orders of magnitude. Conform to expectation, the relative enstrophy isosurface velocity \(v_n\) in the viscous superlayer scales with the Kolmogorov velocity for both flow cases. We connect the integral entrainment coefficient E to the small-scale entrainment and observe excellent agreement between the two estimates throughout the viscous superlayer. The contribution of baroclinic torque to \(v_n\) is negligible, and we show that the primary reason for reduced entrainment in the gravity current as compared to the wall-jet are 1) the reduction of \(v_n\) relative to the integral velocity scale \(u_T\); and 2) the reduction in the surface area of the isosurfaces. 相似文献
80.
Toxizität und Risk Assessment fluvialer Sedimente und Schwebstoffe: Eine kurze Übersicht bisheriger und neuerer Entwicklungen 总被引:1,自引:0,他引:1
M. Brinkmann S. Hudjetz S. Keiter T.-B. Seiler J. Wölz A. V. Hallare H. Hollert C. Cofalla S. Roger H. Schüttrumpf S. U. Gerbersdorf 《Environmental Sciences Europe》2010,22(6):651-655
Background In recent years, sediments have become a central topic of scientific and public discussion as an important factor for determining water quality. While the quality of surface waters in Germany has significantly improved during the past years, highly contaminated sediments still create a considerable threat to the quality of several European catchment areas. Main features Here, we summarize different concepts and methods for the assessment of sediment quality and report on some novel integrative test methods for assessing sediment toxicity including contaminant re-mobilization during simulated re-suspension events. Results and discussion Currently, different approaches for assessment of sediment pollution exist. While instrumental chemical analyses are not suitable to accurately describe sediment toxicity, combinations of biological and chemical test procedures and integrated approaches, for example weight-of-evidence studies and effect-directed analysis (EDA), have the potential to identify key contaminants. Inter-disciplinary studies combining hydrodynamic and toxicological aspects coupled to real exposure of aquatic organisms to contaminants are currently being developed. Conclusions Monitoring and assessment of sediment quality are of increasing importance, not only for national legislation but also for the implementation of the European Water Framework Directive (WFD). Integrated approaches for the determination of sediment stability play a key role in the appropriate sediment-monitoring strategies. 相似文献