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Anne Theenhaus Reinhard Zeitler Wolfgang von Brackel Helmut -Julius Botsch Wolfgang Baumeister Ludwig Peichl 《Environmental Sciences Europe》2002,14(4):229-236
Ecological monitoring of genetically engineered plants (GEPs) is being developed in the Bavarian Environmental Protection Agency. Focusing on oilseed rape (Brassica napus, Cruciferae), a method is being established to measure the impact of the commercial release of GEPs on plant communities. Oilseed rape is known to escape from cultures and to establish outside the fields. It also produces hybrid offspring with wild relatives of the European flora. The study site is located in Bavaria (Germany) and comprises an area of 5700 ha. It is characterized by a mosaic of protected natural habitats in close vicinity to intensively cultivated farmland. In this region species composition and population density of Cruciferae is documented prior to a possible commercial release of GEPs. Furthermore Cruciferae of the study site are tested for the presence of transgenes. Therefore, plant material of selected Cruciferae is randomly sampled. We also test oilseed rape honey from the study site and pollen from pollen traps for the presence of hybrid pollen. The molecular method used is the ‘real-time PCR’. In addition, an intensive monitoring program is established in two types of biotopes, which are located in the study site. Multivariate statistics are being used to correlate plant community data with soil parameters. 相似文献
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Klaus Jung Udo Kristen Johannes Flachowsky Helmut Segner Gerrit Schüürmann 《Environmental Sciences Europe》1997,9(6):317-321
For risk assessment of environmental samples, rapid and sensitive screening assays for detection of toxic potencies are required. Using leachates from waste deposites in the industrial region Leipzig-Halle (Germany) as an example, we present a simple test procedure suitable for the detection of cytotoxic effects of samples. This method, the pollen tube growth test (PTG), works as follows: Pollen of tobacco (Nicotiana sylvestris Spegazz, & Comes) are suspended in mixtures of growth medium and buffered (pH 6,3 to 7,0) dumping ground leachates. After an 18h-incubation period, growth of pollen tubes is quantified by staining with Alcian blue and subsequent measurment of optical density in a photometer. Sample induced inhibition of pollen tube growth is calculated in relation to controls maintained in pure growth medium. The PTG test shows high sensitivity towards leachates of different chemical composition, and it shows good agreement with assay results from luminescent bacteria tests. We conclude that the PTG test is well suited to assess the hazardous potential of aqueous environmental samples. 相似文献
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Interactions of bacteria and fungi on decomposing litter: differential extracellular enzyme activities 总被引:10,自引:0,他引:10
Fungi and bacteria are key agents in plant litter decomposition in freshwater ecosystems. However, the specific roles of these two groups and their interactions during the decomposition process are unclear. We compared the growth and patterns of degradative enzymes expressed by communities of bacteria and fungi grown separately and in coexistence on Phragmites leaves. The two groups displayed both synergistic and antagonistic interactions. Bacteria grew better together with fungi than alone. In addition, there was a negative effect of bacteria on fungi, which appeared to be caused by suppression of fungal growth and biomass accrual rather than specifically affecting enzyme activity. Fungi growing alone had a high capacity for the decomposition of plant polymers such as lignin, cellulose, and hemicellulose. In contrast, enzyme activities were in general low when bacteria grew alone, and the activity of key enzymes in the degradation of lignin and cellulose (phenol oxidase and cellobiohydrolase) was undetectable in the bacteria-only treatment. Still, biomass-specific activities of most enzymes were higher in bacteria than in fungi. The low total activity and growth of bacteria in the absence of fungi in spite of apparent high enzymatic efficiency during the degradation of many substrates suggest that fungi provide the bacteria with resources that the bacteria were not able to acquire on their own, most probably intermediate decomposition products released by fungi that could be used by bacteria. 相似文献
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Environmental Sensitivity Indices (ESI) composed of many field-data are essential for monitoring and control systems. At the
beginning of the last decade an ESI of the German Wadden Sea was developed for use by the relevant authorities. This ESI was
derived by experts semi-manually analysing the extensive field data-set.
An algorithm is presented here which emulates human expert-decisions on the classification of sensitivity classes. This will
permit the necessary regular updates of ESI-determination when new field data become available using automated classifications
procedures. After tuning the algorithm parameters it generates decisions identical to those of human experts in about 97%
of all locations tested. In addition, the algorithm presented also enables erroneous or extremely seldom field data to be
identified. 相似文献