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Using four dynamic criteria, the following environmental changes were evaluated: Global warming; destruction, of the stratospheric ozone layer; eutrophication and acidification of aquatic ecosystems; photochemical smog; reduction of the available area of agricultural soils; loss of species diversity; consumption of resources; reduction of crop yield; forest decline; noise, and smell. These ecosystem changes, or negative effects, were characterized by four dynamic criteria: 1) Regional importance, 2) extent of alteration, 3) resilience and 4) irreversibility. A multi-criteria assessment, accounting simultaneously for all four criteria, requires a generalized concept of order. Here, the concept of partially ordered sets, visualized by Hasse diagrams, was used to derive a priority list of environmental changes. Highest priority was equally assigned to the loss of species diversity, the consumption of resources and the destruction of the ozone layer. However, these ecosystem changes are incomparable to each other concerning the four criteria used and thus require different management strategies.  相似文献   
53.
W. Thumm  R. Brü  ggemann  D. Freitag  A. Kettrup 《Chemosphere》1992,24(12):1835-1843
EC50 values of different nitroparaffins were determined by a photobacterium phosphoreum toxicity test. Octanol/water partition coefficients were determined by a reversed phase HPLC method. From these experimental data quantitative structure activity relationships were deduced which point to a dependence of toxicity on a “form factor” that includes the number of methyl and methylene groups in a molecule. The hypothesis will be formulated that the specific effects depend on the number of methylgroups and an equation for specific effects is given.  相似文献   
54.
This paper describes remote monitoring of air pollutant emissions by a mobile lidar (light detection and ranging)/ sodar (sound detection and ranging) system. First, measurements are carried out in the flue gas plume of a public power plant. The investigations focus mainly on quantifying SO2 emissions, but the uncertainties of such measurements are also emphasized. Furthermore, an example providing valuable data sets for the development and validation of plume dispersion models is outlined with measurements of the dilution of SO2 along the plume axis. Series of repeated determinations of SO2 emissions show a large variation in the obtained flux values, with moderate margins of error. Incomplete recording of the plume within the individual lidar scans, induced by strong looping movements of the flue gas plume, predominantly causes the variations of flux values. Therefore, the highest flux values determined are considered to be the most exact. This is verified by a comparison of measured fluxes with in situ measurements made by the plant operators. The results further indicate that lidar measurements illustrate the location and dimension of aerosol plumes better than the location and dimension of the plumes of gaseous compounds. The wind direction affecting the plume at any moment can be determined faster by lidar than by sodar because the latter requires much longer time intervals of signal averaging. Measurements show higher concentrations of SO2 compared with results from a Gaussian plume model for periods of less than 5 min after dispersion. The findings emphasize the suitability of remote sensing for detecting emissions and for investigating the propagation and dilution of air pollutant plumes.  相似文献   
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A ground-based Differential Absorption Lidar was employed to study the dynamics of atmospheric O3 within the planetary boundary layer of a basin in the 'Fichtelgebirge' mountains, NE Bavaria. In particular, the night-time dynamics of O3 linked to the ground were investigated. The Lidar system measured vertical profiles of O3 up to 1 km above ground. For detailed analysis of the night-time dynamics of ozone, supplementary data from three ground-based stations (measuring mixing ratios of O3 and NO(x), as well as meteorological parameters) are essential. The Lidar results could be evaluated with these data from various altitudes above the basin floor. For the station with the largest (vertical) distance to the ground-based Lidar, the agreement was very good at all times. The Lidar method proved to be useful for examining the spatial distribution of O3. The observed night-time decrease of O3 at the bottom of the basin was due to deposition and to advection of air masses containing less O3 from the mountain slopes.  相似文献   
56.
In eine ?kotoxikologische Bewertung von Schadstoffen müssen die Ergebnisse von Wirkungstests einflie?en. Die Qualit?t der Bewertung im ?kosystemaren Kontext steht und f?llt mit der ?kosystemaren Qualit?t der Tests. In der vorliegenden Arbeit wird eine Bestandsaufnahme aquatischer Wirkungstests (unabh?ngig von bestehenden legislativen Vorgaben) vorgenommen, und es werden die Ergebnisse in einer Tabelle zusammengestellt, die Einsatzbereiche, Anwendbarkeit für mathematische Wirkungsmodellierung und ?kosystemare Relevanz enth?lt. Die hieraus resultierende Tabelle ist schwer zu überblicken und Zusammenh?nge zwischen bestimmten Wirkungstests sind kaum überschaubar. So ist auch eine Einstufung der aquatischen Wirkungstests ohne zus?tzliche mathematische Hilfsmittel schwierig. Hier wird gezeigt, wie anhand der Technik derHasse-Diagramme die Einstufung der Wirkungstests nach ihrer Qualit?t erleichtert wird. Es zeigt sich u.a., da? es keinen Test gibt, der alle Anforderungen gleichzeitig erfüllt. Einerseits gibt es sechs Tests, die — nach ihren Einsatzbereichen und nach ihrer Umsetzbarkeit für die mathematische Modellierung beurteilt — zwar optimal sind, aber keine ?kosystemare Relevanz aufweisen. Andererseits gibt es zwei Tests, die besonders ausgezeichnet sind: Einer (Test 8), der drei Einsatzbereiche aufweist und gleichzeitig sowohl für die mathematische Modellierung geeignet, als auch ?kosystemar relevant ist, und einer, der in zwei anderen Einsatzbereichen positiv beurteilt wurde und noch ?kosystemar interessant ist (Test 54). Es zeigt sich, da? zwischen Tests mit breitem Einsatzbereich und solchen, die ?kosystemar relevant sind, eine Lücke klafft. An evaluation of pollutants depends on the ecotoxicological quality of the effect tests carried out. In this paper a compilation of aquatic tests is given independently on administration needs. The results are summarized in a table listing fields of application, importance for mathematical modelling and ecological relevance. The table includes 55 tests and 8 attributes characterizing each tests The interpretation of the results listed in this table is hardly feasible. An appropriate tool to rank the tests is the technique ofHasse-diagrams. Using this tool it can be deduced that no test fulfills all demands. There are six tests which are optimal with respect to applicability and mathematical modelling. However, they have no relevance for ecosystems. Only two tests are optimal with respect to ecotoxicology, There is still a gap between tests with a wide field of applications and those tests which are relevant with respect to ecotoxicology.  相似文献   
57.
Zusammenfassung  Sollen Chemikalien oder Umweltbelastungen ?kotoxikologisch beurteilt werden, so erfordert die Komplexit?t ?kosystemarer Zusammenh?nge, da? Bewertungsverfahren Informationen m?glichst nicht aggregieren soilten. Es gibt keine ?kologisch begründete, allgemein verwendbare Zielfunktion. Die Technik, dennoch beispielsweise Chemikalien miteinander vergleichen zu k?nnen, beruht auf der Verallgemeinerung des Ordnungsbegriffs und der Visualisierungsmethode durch Hasse-Diagramme. Am Beispiel von sechs Chemikalien wird das Verfahren erl?utert und gezeigt, da? ungünstige Einstufungen von Chemikalien verschiedene Ursachen haben k?nnen, die dann auch unterschiedliche ?kotoxikologische Konsequenzen bewirken.   相似文献   
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An evaluation of pollutants depends on the ecotoxicological quality of the effect tests carried out. In this paper a compilation of aquatic tests is given independently on administration needs. The results are summarized in a table listing fields of application, importance for mathematical modelling and ecological relevance. The table includes 55 tests and 8 attributes characterizing each tests The interpretation of the results listed in this table is hardly feasible. An appropriate tool to rank the tests is the technique ofHasse-diagrams. Using this tool it can be deduced that no test fulfills all demands. There are six tests which are optimal with respect to applicability and mathematical modelling. However, they have no relevance for ecosystems. Only two tests are optimal with respect to ecotoxicology, There is still a gap between tests with a wide field of applications and those tests which are relevant with respect to ecotoxicology.  相似文献   
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