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41.
CO concentrations were measured in five kindergartens, one children's hospital and two homes for aged, practically without indoor sources, all situated in the city centre, for ten random days in winter and ten in summer. The indoor CO concentrations were the result of the distance from and the traffic density in the nearest street, of general pollution level, seasonal differences, day-to-day variations and daily cycle of air pollution, the vicinity of traffic having a dominant influence. Therefore location of institutions for sensitive population groups in old city centres within a block of houses seems to be a suitable solution as far as exposure to CO is concerned.Revised version of a paper presented as poster at the VIth World Congress on Air Quality, Paris 1983.  相似文献   
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The purpose of this paper is to present a study of impact assessment of the traffic-induced vibration on a buried natural gas transmission pipeline. The basic assumption in this study is that the traffic on pipeline-transportation route crossing might have a significant impact on natural gas pipeline structural integrity due to the traffic-induced vibration which propagates from the road surface through the soil and excites the buried natural gas pipeline. The resulting dynamic stress causes pipeline material fatigue loading which consequently may cause pipeline failure with the gas release into the environment exposing the population and the buildings in pipeline vicinity to a significant threat. The experiment on operating buried natural gas pipeline was conducted where measurements were performed on the road surface, the two operating buried natural gas pipelines of external diameter 500 mm and 250 mm and on corresponding casing pipes. The measurement data analysis was performed and the results were used for determination of pipeline lifetime period in the model for theoretical estimation of pipeline lifetime which has been exposed to traffic-induced vibration. The findings of the study in this paper show that the traffic-induced vibration on given buried natural gas pipeline is detectable, however this vibration, compared to the other factors which are influencing pipeline's structural integrity, does not have a significant impact on pipeline lifetime period.  相似文献   
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Poultry manure is a significant source of nitrogen, but small amount of carbon needs to be added for faster degradation of organic matter in composting process. Composting of poultry manure mixed with wheat straw was carried out in specially designed reactors (32 L) under controlled laboratory conditions over 13 days. The aim of the study was to determine the influence of wheat straw addition to poultry manure on performance of composting process in terms of the following: the substrate temperature, carbon dioxide, ammonia, pH, electrical conductivity and organic matter. According to the results, the mixture of 83% poultry manure and 17% wheat straw (dw) among three different mixtures used in this research provided the best conditions for composting process.  相似文献   
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Canopy leaching of nutrients and metals in a mountain spruce forest   总被引:1,自引:0,他引:1  
Precipitation and throughfall fluxes of major ions, nutrients (C, N, P), and metals (Al, Fe, Mn), and the chemical composition of litter fall and living plant tissue in Norway spruce stands (the Bohemian Forest; Czech Republic), were used to evaluate how microbial processes and decay of plant tissue in canopies influence canopy leaching (CL) of elements. Proton exchange for Mg2+, Ca2+, and K+ in decaying biomass and co-transport of Ca2+ and K+ out of plant cells with organic acid anions were the most likely processes contributing to CL of base cations. The CL of total P and N (and also NO3?) was minor. Important proportions of the N and P mineral forms were transformed to organic forms by microbial processes (primary and bacterial production), with the respective CL of ?13.9 and 16.4 mmol m?2 yr?1 for NH4+ and organic N, and ?0.33 and 0.22 mmol m?2 yr?1 for dissolved reactive P (DRP) and organic P. Most of particulate P and N in throughfall (~90%) originated from microbial DRP and NH4+ transformations, but particulate C mostly came from the fragmentation of plant tissue (58%). Among metals, CL was not observed for Al, was small for Fe (0.3 mmol m?2 yr?1), and greatest for Mn (0.9 mmol m?2 yr?1) due to leaching from decaying tissue by acidic precipitation.  相似文献   
47.
Ambient particles vary greatly in their ability to affect visibility, climate and human health. The fine fraction of aerosol is responsible for greater and wider effects on human health; thus, investigation of this fraction is very important. Continuous measurements of PM2.5 (particulate matter below 2.5 μm in size) concentrations at the Preila monitoring station started in 2003. During a period of 2 years, the episodes of high daily and semi-hourly concentrations of PM2.5 were measured. These episodes did not depend on the season or time of day. The substantial role of long-range transport of pollutants to these increases in concentration was shown using chemical and statistical analysis. It was found that most of the severe episodes occurred when air masses came from a specific site besides it was established that air masses of different origin were characterized by different mixing layer depth. Lower mixing depth was observed in air masses characterized by higher observed concentrations at the measuring site and vice versa. PM2.5 concentrations showed diurnal and seasonal variations whose pattern reflected the regional origin of the aerosol. The regional pollution level was evaluated by the statistical analysis of PM2.5 concentrations. The background annual average of PM2.5 mass concentration for the eastern coast of the Baltic Sea was 15.1 ± 0.8 μg m−3.  相似文献   
48.
Inclusive fitness theory predicts that cost of tolerant behaviour during competitive interactions is lower for relatives than for nonrelatives. Many studies have examined the effect of relatedness on behaviour within social groups. In contrast, kin selection acting among groups has received less attention. The genetic structure of African lion (Panthera leo) populations creates a strong possibility that kin selection among groups modifies behaviour during group conflicts. We used playback experiments and genetic data to investigate the importance of relatedness during simulated territorial disputes in lions. However, we found no effect of relatedness on territorial behaviour. Degree of relatedness did not affect the decision to approach simulated intrusions, nor did it affect the behaviour during approaches. The decision to approach was instead affected by position within the territory and consecutive playback number (a measure of habituation). For playbacks that did elicit an approach, the speed of response was not detectably affected by relatedness, but was affected by odds (the ratio of residents to intruders), number of intruders, number of bouts, presence of cubs, position within the territory, temperature and playback number. Although responses were unaffected by relatedness, it remains possible that other aspects of behaviour during natural encounters among prides are affected by kin selection.Communicated by L. Sterck  相似文献   
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Here we present the methodology used for terrestrial biodiversity analysis and site selection in Phase B of the UNDP/GEF COAST project. The analysis was focused on the problem of biodiversity evaluation in four Croatian counties stretching from sea level to the highest mountain in Croatia. Data on habitats, vascular flora, and fauna (mammals, birds, reptiles, amphibians, butterflies, ground beetles, and underground invertebrates) were collected and analyzed for each of the four counties. Emphasis was given to the richness of endangered species and the rarity of endemic species. Based on the spatial analyses of habitat, fauna, and flora data, four to six areas were selected from each county and ranked according to their biodiversity importance. Overlap between areas important for richness and those important for rarity was highest for data on flora (65.5%) and lowest for data on fauna (16.7%). When different data sets were compared, the lowest overlap was between flora and fauna (17.1%) and largest between fauna and habitats (23.9%). Simultaneous overlap among all three data sets was found in just 6.5% of the overall selected areas. These results suggest that less specific data, with respect to taxa threat status, could better serve as surrogate data in estimating overall biodiversity. In summary, this analysis has demonstrated that Dalmatia is a region with a high overall biodiversity that is important in a broader European context.  相似文献   
50.
The concentrations of heavy metals Pb, Cd, Cu, Zn and Hg, benzo[a]pyrene and oil products (C15–C28) in bulk (wet and dry) atmospheric deposition in Vilnius city in 2005–2006 were analysed. The highest flux to the ground surface of the city residential area, reaching 1,680 mg m?2 year?1, was determined for oil products, which in atmospheric bulk deposition was estimated to be mainly in the form of solid sediments. Among heavy metals, the highest flux was determined for Zn (113.5 mg m?2 year?1), while the lowest flux was determined for Hg (0.06 mg m?2 year?1). The flux of investigated pollutants ranges from a few times, or for some pollutants, up to one order of magnitude higher at the urban sampling site in comparison to residential or background sites. Some hundred tons of oil products, approximately 52 tons of zinc and a considerably lower amount of mercury, benzo[a]pyrene and cadmium deposit yearly to the ground and water surface of Vilnius city. Metallic constructions related to transport and buildings, automobile exhausts, spills of fuel and lubricants are suggested to be the factors which result in the accumulation of high amounts of heavy metals, oil products and other pollutants on the ground surface of the city.  相似文献   
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