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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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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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To decouple economic growth from environmental degradation, the Chinese government proposed the circular economy (CE) strategy as part of its 11th 5-Year Plan. This strategy expands the application of CE from individual enterprises to eco-industrial parks (EIPs) and to the cities, provinces, and regions. We carried out field studies in three EIPs in Baotou, Suzhou, and Shanghai. In this paper, we discuss the current state of CE and the sustainable development of EIPs in China. We first provide detailed information on the three EIPs' infrastructures, preferential policies, CE frameworks, and eco-chains. We then examine the status of sustainable development in the three EIPs from the perspectives of socio-economic, resource and material efficiency, and environmental performance. The results indicate that the overall performance of the three EIPs is reasonably good with respect to socio-economics, resources and materials, and efficiency and environmental protection, whereas green management is rather weak and thus requires further improvement. We found that the CE frameworks along with eco-chains within the EIPs are effectively improving resource and material efficiency. Moreover, we demonstrate that there are positive associations among socio-economic, resource and material, and environmental indicators. Given the large presence of EIPs in the local economies, these results suggest that EIPs play a key role in promoting sustainable development in China.  相似文献   
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Planetary Stewardship in an Urbanizing World: Beyond City Limits   总被引:1,自引:0,他引:1  
Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security.  相似文献   
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