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131.
In this study the effects of nickel (NiCl2) administered in drinking water (0.02; 0.2 and 2.0 mg NiCl2/L for 28 days) on laying hen body weight, egg production and egg quality is reported. Growth parameters during the experiment were significantly decreased mainly in the group with the highest nickel concentration. In total egg production dose-dependent decrease in all experimental groups was found. Egg weight was mainly affected in the group with the highest nickel concentration. Specific egg weight was not altered. Albumen weight and albumen content was significantly decreased in groups with the highest nickel concentration in comparison with the control group. Egg yolk analysis detected significantly decreased yolk weight in the group with the highest nickel experimental level. In yolk color a significant difference was detected between the group receiving 0.02 and 0.2 mg NiCl2/mL. Eggshell compactness was increased in all experimental groups what could be induced by altered mineralization of eggshell. Results of this study clearly report a negative effect of nickel as an environmental pollutant on laying hen body weight, egg production as well as egg quality.  相似文献   
132.
Monitoring of forest condition and ozone (O3) at 83 sites in France, Italy, Luxenbourg, Spain and Switzerland resulted in a number of findings in relation to the knowledge of O3 exposure (concentration and cumulative AOT40), feasibility of the assessment of stomatal O3 flux and relationships between O3 and crown defoliation of beech and visible symptoms on native vegetation. However, the project provides evidence of issues to be addressed within the current monitoring system (data quality, validation sites and response indicators) and indications as to how the monitoring of O3 risk in the context of an effect-oriented monitoring program can be improved.  相似文献   
133.
Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected quaternary ammonium compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 microg/kg for sediments and from 2 to 5 microg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylammonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.  相似文献   
134.
Ozone and forests in South-Western Europe   总被引:1,自引:0,他引:1  
The paper provides basic information about background, objectives and structure of O3SWE (Ozone at the permanent monitoring plots in South-Western Europe), an international co-operative project aimed at evaluating O3 concentrations, cumulative exposure, uptake and effects on forest vegetation in four countries of South-Western Europe (France, Italy, Luxenbourg, Spain and Switzerland). The project covers a total of 83 permanent plots of the EU and UN/ECE intensive forest monitoring programme and span over three years of investigation (2000-2002). The O3SWE project aims to demonstrate how, using data collected routinely in an intensive forest monitoring network, O3 exposure, flux and effects can be assessed and exceedances critically evaluated.  相似文献   
135.
The objective of this study was to establish whether EU and UN-ECE/ICP-Forests monitoring data (i) provide the variables necessary to apply the flux-based modeling methods and (ii) meet the quality criteria necessary to apply the flux-based critical level concept. Application of this model has been possible using environmental data collected from the EU and UN-ECE/ICP-Forests monitoring network in Switzerland and Italy for 2000-2002. The test for data completeness and plausibility resulted in 6 out of a possible total of 20 Fagus sylvatica L. plots being identified as suitable from Switzerland, Italy, Spain, and France. The results show that the collected data allow the identification of different spatial and temporal areas and periods as having higher risk to ozone than those identified using the AOT40 approach. However, it was also apparent that the quality and completeness of the available data may severely limit a complete risk assessment across Europe.  相似文献   
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One possible mechanism for the (co-)evolution of seemingly novel male traits and female preferences for them is that males exploit pre-existing female biases, and livebearing fishes (Poeciliidae) have been at the forefront of this research for almost two decades. Here, using 13 poeciliid species from four different genera, we tested whether mustache-like rostral filaments found in males of some Mexican molly (Poecilia sphenops) populations could have evolved due to exploitation of a pre-existing female bias. While Mexican mollies were the only species with a significant female association preference for mustached males, we also did not find any species exhibiting significant aversion for mustached males; rather, variance in female preference scores was large throughout. For example, more than 25% of females spent twice as much time with the mustached male compared to the non-mustached male in most species, but even 31% of Mexican molly females spent more time near the non-mustached male. Hence, a comparison of the strength of preference was inconclusive. We discuss the possibility that the female preference of P. sphenops for mustached males could be due to a female pre-existing bias (sensu lato), even if population means were not significant for species other than P. sphenops. This highlights the importance of distinguishing between population means and individual preferences when interpreting mate choice, and thus, adds depth to the concept of mating preferences as a motor for evolutionary change.  相似文献   
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The shores of many Central European lakes located in the hinterland of large conurbations are heavily endangered by intensive settlement, traffic, sewage input, manipulation of the water level, tourism and recreation. This increasing impact has negatively affected the function of the lake shore in respect to conservation and species protection, to water protection and its importance for recreation. This paper describes the overlap of the multiple uses and the precautions planned since 1981 on the national and international level to guarantee the essential multiple functionality, e.g. as drinking water reservoir for the conurbations in the northern part of Baden-Württemberg, as supraregional centre for water sports and tourism, and as an important environment for endangered plant and animal species. Management measures include regional planning as well as the international water protection and preservation with many contributions from non governmental international organisations Given a high agreement concerning these aims, many indispensable actions could successfully be realised on the political and administrative level. On the basis of 14 topics we follow the development since 1981, most recently also driven by the EU (FFH/Natura 2000), Water framework directive). Backlogs became obvious for four topics: 1. The lack of efficient reviews on completed measures, 2. gaps in basic understanding, 3. The dragging harmonisation of an intergrated shore protection program across the borders, and 4. the lack of concepts for a sustainable development including plans for monitoring.  相似文献   
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