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521.
The acute whole sediment bioassay with the estuarine and marine amphipod Corophium volutator (Pallas) is broadly used within Europe. Hitherto, the test is carried out with field-collected animals. In order to provide a more standardized and continuously available test organism reproduction and growth experiments were performed for a period of one year in laboratory under simulated summer conditions (light/dark 16:8 at 15, 19, and 23 degrees C). C. volutator was the first time reproduced successfully in laboratory for several generations and independent from its natural life cycle also in winter. The females produced two to three broods with a mean number of 96 offspring. A mean growth rate of 0.07 mm per day was determined at 15 degrees C. The reproduction and growth experiments provide consequently the essential base for the development of a chronic toxicity test with C. volutator. 相似文献
522.
Loibl W Bolhàr-Nordenkampf HR Herman F Smidt S 《Environmental science and pollution research international》2004,11(3):171-180
GOAL, SCOPE AND BACKGROUND: Ozone is the most important air pollutant in Europe for forest ecosystems and the increase in the last decades is significant. The ozone impact on forests can be calculated and mapped based on the provisional European Critical Level (AOT40 = accumulated exposure over a threshold of 40 ppb, 10,000 ppb x h for 6 months of one growing season calculated for 24 h day(-1)). For Norway spruce, the Austrian main tree species, the ozone risk was assessed in a basis approach and because the calculations do not reflect the health status of forests in Austria, the AOT40 concept was developed. METHODS: Three approaches were outlined and maps were generated for Norway spruce forests covering the entire area of Austria. The 1st approach modifies the AOT40 due to the assumption that forests have adapted to the pre-industrial levels of ozone, which increase with altitude (AOTalt). The 2nd approach modifies the AOT40 according to the ozone concentration in the sub-stomata cavity. This approach is based on such factors as light intensity and water vapour saturation deficit, which affect stomatal uptake (AOTsto). The 3rd approach combines both approaches and includes the hemeroby. The pre-industrial ozone level approach was applied for autochthonous ('natural') forest areas, the ozone-uptake approach for non-autochthonous ('altered') forest areas. RESULTS AND DISCUSSION: The provisional Critical Level (AOT40) was established to allow a uniform assessment of the ozone risk for forested areas in Europe. In Austria, where ozone risk is assessed with utmost accuracy due to the dense grid of monitoring plots of the Forest Inventory and because the continuously collected data from more than 100 air quality measuring stations, an exceedance up to the five fold of the Critical Level was found. The result could lead to a yield loss of up to 30-40% and to a severe deterioration in the forest health status. However, the data of the Austrian Forest Inventory and the Austrian Forest Damage Monitoring System do not reflect such an ozone impact. Therefore, various approaches were outlined including the tolerance and avoidance mechanisms of Norway spruce against ozone impact. Taking into consideration the adaptation of forests to the pre-industrial background level of ozone, the AOT40 exceedances are markedly reduced (1st approach). Taking into account the stomatal uptake of ozone, unrealistic high amounts of exceedances up to 10,000 ppb x h were found. The modelled risk does not correspond with the health status and the wood increment of the Austrian forests (2nd approach). Consolidating the forgoing two approaches, a final map including the hemeroby was generated. It became clear that the less natural ('altered') forested regions are highly polluted. This means, that more than half of the spruce forests are endangered by ozone impact and AOT40 values of up to 30,000 ppb x h occur (3rd approach). CONCLUSIONS: The approaches revealed that a plausible result concerning the ozone impact on spruce forests in Austria could only be reached by combining pre-industrial ozone levels, ozone flux into the spruce needles and the hemeroby of forests. 相似文献
523.
Wolfgang Ahlf 《Umweltwissenschaften und Schadstoff-Forschung》1995,7(2):84-91
Die übersicht stellt notwendige Komponenten einer ?kotoxikologischen Bewertung für kontaminierte Sedimente vor. Die jeweiligen
St?rken und Schw?chen der ?kologischen und toxikologischen Verfahren werden herausgearbeitet. Die bestehenden Biotestmethoden
werden auf Grundlage der bekannten Expositionswege zu einer Testkombination für die Anwendung in der Praxis ausgew?hlt. Ein
integriertes Bewertungsschema, bestehend aus den Komponenten Sedimentchemie, Sedimenttoxizit?t undin situ Untersuchungen, macht eine flexible und abgestufte Vorgehensweise m?glich und berücksichtigt den Stand der Forschung. Die
Gesichtspunkte der überwachungsbeh?rden und die der ?kologischen Forschung ergeben eine dichotome Zielsetzung, die z.T. mit
den glcichen Methoden bearbeitet werden kann. 相似文献
524.
R. Subramanian Neil M. Donahue Anna Bernardo-Bricker Wolfgang F. Rogge Allen L. Robinson 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):8002-8019
We present estimates of the vehicular contribution to ambient organic carbon (OC) and fine particle mass (PM) in Pittsburgh, PA using the chemical mass balance (CMB) model and a large dataset of ambient molecular marker concentrations. Source profiles for CMB analysis are selected using a method of comparing the ambient ratios of marker species with published profiles for gasoline and diesel vehicle emissions. The ambient wintertime data cluster on a hopanes/EC ratio–ratio plot, and therefore can be explained by a large number of different source profile combinations. In contrast, the widely varying summer ambient ratios can be explained by a more limited number of source profile combinations. We present results for a number of different CMB scenarios, all of which perform well on the different statistical tests used to establish the quality of a CMB solution. The results illustrate how CMB estimates depend critically on the marker-to-OC and marker-to-PM ratios of the source profiles. The vehicular contribution in the winter is bounded between 13% and 20% of the ambient OC (274±56–416±72 ng-C m−3). However, variability in the diesel profiles creates uncertainty in the gasoline–diesel split. On an OC basis, one set of scenarios suggests gasoline dominance, while a second set indicates a more even split. On a PM basis, all solutions indicate a diesel-dominated split. The summer CMB solutions do not present a consistent picture given the seasonal shift and wide variation in the ambient hopanes-to-EC ratios relative to the source profiles. If one set of source profiles is applied to the entire dataset, gasoline vehicles dominate vehicular OC in the winter but diesel dominates in the summer. The seasonal pattern in the ambient hopanes-to-EC ratios may be caused by photochemical decay of hopanes in the summer or by seasonal changes in vehicle emission profiles. 相似文献
525.
Calmano W 《Environmental science and pollution research international》2004,11(2):126-133
In the preceding series of contributions to ESPR typical examples from actual fields of water chemistry were presented on various topics: integrated water quality management, diagnosis of water bodies, therapy of aquatic systems, and fitness for aquatic systems. These contributions clearly showed the need and importance of more intensive research. In the principle committee III 'Basic Research' of the Water Chemical Society, various expert groups work on scientific backgrounds in these fields. Some relevant topics are selected in this outlook, mainly on interactions of solids with water, the role of environmental colloids, the development of modern biochemical methods for diagnosis, the impact of chemical speciation on bioavailability and water technology, and the development of advanced methods in water treatment technology. Innovative approaches to understand the interactions between pollutants, water and solids are crucial for assessment of contaminants with biochemical and analytical methods, for the development of new efficient technologies and for application of treatment methods with little or no waste and by-product formation. 相似文献
526.
Schoknecht U Wegner R Horn W Jann O 《Environmental science and pollution research international》2003,10(3):154-161
Methods for the determination of biocide emissions from treated materials into water and air were developed and tested in order to support a comparative ecological assessment of biocidal products. Leaching tests, experiments with simulated rain, extraction cleaning of carpets and emission chamber tests were performed with a series of treated materials. The experiments focused on the effect of changes in the procedure as well as characteristics of the specimens and demonstrate the suitability of the proposed methods for biocides of different product types. It was demonstrated that emissions of biocides into water can be compared on the basis of leaching tests in which the emission kinetics of the active ingredients are recorded. However, the water volume per surface area and the timetable for water changes have to be defined in such tests. Functions of flux rates related to time can be well described for inorganic compounds, whereas modelling of the data is more complicated for organic substances. Emission chamber tests using 20-litre and 23-litre glass exsiccators, originally developed to study volatile organic compounds, were successfully adapted for the investigation of the emission of biocides from treated materials which are usually semi volatile organic compounds. However test parameters and the method of analysis have to be adapted to the substances to be determined. Generally, it was found that the emission curves for the semi volatile organic compounds investigated differ from those of volatile organic compounds. 相似文献
527.
Wolfgang Strasdas 《生态毒理学报》2002,24(3):12-15
定义 围绕这个主题 , 虽然有很多不同的看法 , 笔者却认为 , 由于具有一整套明确目标 , " 生态旅 游 " 应该被认作是一个可以发展的概念 , 没必要把它当作一个市场 ( 市场指得是 " 大自然旅 游 " ) . 因此 , 生态旅游被认定为大自然旅游的一种具有可持续能力的形式 , 力争得到环境 、社会和文化的和谐共处 , 以及创造经济和其他的效益 , 特别是在为当地农村居民造福和自 然保护方面 . 相似文献
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