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61.
62.
Part 2 presents measures at the city scale, which are distinguished into object- and area-related means. The former ones include emission reduction, energy gaining and saving, as well as the climate-improving impact of rooftop and façade greening. Area-related means refer to the reduction of radiation temperature through shading and transpiration as well as impact of urban green areas of different size on the urban climate. Furthermore the opportunities to use subsurface urban heat island as an energy-reservoir for cooling or heating are discussed.  相似文献   
63.
The crustacean Monoporeia affinis Lindström was exposed to two different concentrations of bleached kraft mill effluent (BKME) containing, originally, 8.3 mg/g organic chlorine determined as adsorbable organic halogen (AOX). The swimming activity of the animals was recorded by pairs of infra-red sensitive photocells attached to 5.6 1 aquaria having a seawater inflow rate of 12 ml/min. The test sequence included a control phase, an exposure phase and a recovery phase. During the exposure phase the total swimming activity decreased in three of the four test aquaria containing effluent, indicating that the animals had retreated into the sediment. Total activity increased during the recovery phase and, in the case of the lower organic chlorine concentration, activity almost achieved the original control-phase level. Statistical differences in swimming activity changes during experiment were evaluated using ANOVA. Experimental methods are explained in detail.  相似文献   
64.
Lepidophagous (scale-eating) blue-striped fangblennies (Plagiotremus rhinorhynchus Bleeker 1852) are often found sympatrically with the bluestreak cleaner wrasse (Labroides dimidiatus Valenciennes 1839). They have some resemblance to the juvenile L. dimidiatus and have previously been reported as aggressive cleaner wrasse mimics. We observed 14 P. rhinorhynchus on a small area in the barrier reef near Hoga Island, Indonesia to assess the effects of client size on the behaviour and attack success of fangblennies: our results suggest that fangblennies are selective with regard to victim size; fish avoided by the fangblennies are significantly larger than those not avoided and attack success is significantly higher at intermediate victim size classes. The behaviour of the victims also has a significant direct effect on the foraging success of the fangblennies; where the potential victim posed, 63.6% were ignored by the fangblenny and only 7.4% of attacks were successful on posing fish as opposed to a surprise attack success rate of 71.6%. Overall, victims which exhibited the pose behaviour were significantly smaller in size. It appears likely that the predatory strategy of these fangblennies varies with victim size and that mimicry plays a minor role in attracting potential victims. We suggest that in common with other mimetic fish the resemblance of fangblennies to juvenile bluestreak cleaner wrasse allows them to actively hunt in areas where adult cleaners are common thus, indirectly improving their feeding opportunities.  相似文献   
65.
Sediment samples from the upper Danube River in Germany have previously been characterized as ecotoxicologically hazardous and contaminants in these sediments may contribute to the observed decline of fish populations in this river section. For the investigation of sediment toxicity there is a need for development, standardization and implementation of in vivo test systems using vertebrates. Therefore, the main objective of this study was to apply and evaluate a recently established fish gill EROD assay as a biomarker in sediment toxicity assessment by using extracts of well characterised sediment samples from the upper Danube River. This to our knowledge is the first application of this novel assay to sediment extracts. Sediments from four different sites along the upper Danube River were Soxhlet-extracted with acetone and dissolved in DMSO. Three-spined sticklebacks (Gasterosteus aculeatus L.) were exposed for 48 h to various concentrations of the extracts, to the positive control beta-naphthoflavone or to the solvent. Measurements of EROD activity in gill filaments and liver microsomes followed the exposure. Concentration-dependent induction of EROD in both gill and liver was found for all sediment extracts. The highest EROD-inducing potency was determined for extracts of sediments from the sites "Opfinger See" and "Sigmaringen" and the EROD activities in gill and liver correlated well. The results from the gill and liver assays were in accordance with in vitro results of previous investigations. The EROD activities measured in the present study corresponded with the concentrations of PAHs, PCBs and PCDD/Fs in the sediment samples derived in a previous study. The sticklebacks in this study were in the reproductive phase and a stronger EROD induction was obtained in the females than in the males. Implementation of the EROD assay in testing of sediment extracts gave highly reliable results which make this assay an ecotoxicologically relevant method for assessment of contamination with Ah receptor agonists in sediments.  相似文献   
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67.
If genetically modified organisms are to contribute to welfare they must be considered in the context of sustainable development. Biosafety implies considering the environmental, economic and social dimensions of sustainable development. These dimensions can be interpreted through the principles of precaution, polluter pays and public participation. In this article, these key biosafety principles are operationalised and ways of implementing them in society are discussed. A comparison is made between the principles and the present EU law for deliberate release of GMOs. It is concluded that several improvements in EU policy are necessary to ensure sustainable development really is promoted.  相似文献   
68.
Population models are increasingly being considered as a tool for pesticide risk assessment in order to evaluate how potential effects act on the population level and population recovery. While the importance and difficulties of such models have been discussed by various authors during the past decade, mainly with a focus on how to describe or develop such models, several biological and methodological aspects have never been addressed so far, which are relevant for the application of models in risk assessment. These include a critical review of our knowledge of a species, the use of field data by taking methodological constraints into account, how to include uncertainty in model validation or how to measure effects. Although these aspects will be critical for the acceptance of population models by authorities, most of them apply not only to population models, but also to standard risk assessment. In the present article, we give practical recommendations for addressing these questions in population level risk assessments.  相似文献   
69.
For the application of our method for the sequential extraction of heavy metals from microsamples presented in part 1 (“Sequentielle Schwermetallextraktion von Mikroproben” — “Sequential Extraction of Heavy Metals from Micro Samples”) an investigation was carried out to evaluate airborne dust fallout and street sediments at two urban sites where different heavy metal immission rates occur due to traffic influence. In the street sediments the total concentrations of zinc, copper and lead was three to fivefold higher in the silt and clay fraction (< 63 μm) than in the particle size fraction (< 1,12 mm), but showed nearly the same mobilisation behaviour. The dust samples showed equal mobilisation behaviour as the street sediments for copper and lead, while zinc was considerably more mobile in the dust samples: In extraction steps I–IV (I: mobile fraction; II: easily deliverable fraction; III: fraction bound to manganese oxides; IV: fraction bound organic to matter) zinc, copper and lead in street sediments, as well as copper and lead in dust samples, were dissolved to 40–70%, whereas about 80% of zinc in the dust samples was already dissolved in extraction step I.  相似文献   
70.
Leachates of anti-fouling paints for use on ships and leisure boats are examined for their ecotoxicological potential. Paint leachates were produced in both 7‰ artificial (ASW) and natural seawater (NSW) and tested on three organisms, the bacterium Vibrio fischeri, the macroalga Ceramium tenuicorne, and the crustacean Nitocra spinipes. Generally, leaching in ASW produced a more toxic leachate and was up to 12 times more toxic to the organisms than was the corresponding NSW leachate. The toxicity could be explained by elevated concentrations of Cu and Zn in the ASW leachates. Of the NSW leachates, those from the ship paints were more toxic than those from leisure boat paints. The most toxic paint was the biocide-free leisure boat paint Micron Eco. This implies that substances other than added active agents (biocides) were responsible for the observed toxicity, which would not have been discovered without the use of biological tests.  相似文献   
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