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991.
Soil nematode communities (taxa composition, trophic structure, ecological indices) in the area of metallurgical factory (Oravské ferozliatinárske závody) in ?iroká, Northern Slovakia were investigated in 2009. The factory belongs to main sources of emissions originated by ferroalloy production in this region. Four sites (meadows) were selected in a downwind direction from the factory: site A was located 0.85 km far from the factory, and the other sites were maintained in approximately 2-km intervals from each other. Chemical analysis of soil samples showed low concentrations of heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn), with all values being under Slovak limit concentrations of heavy metals in soils. Only the Cd content in the soil sample from site A slightly exceeded the allowable threshold, but it was decreasing with the distance from the factory, similarly as remaining metals except Cr, with slightly increasing trend of concentration. Within 64 identified nematode genera, the Helicotylenchus, Paratylenchus, Pratylenchus, Acrobeloides, Cephalobus and Rhabditis were most common and eudominant. This was clearly reflected on the trophic structure of nematode communities, where plant feeding nematodes and bacteriovorous prevailed. Significant negative correlation (P?相似文献   
992.
Toxic metals (Pb, Cd, As and Hg) and organochlorine residue levels were measured in hake (Merluccius merluccius) from the Marmara Sea. Biota samples were collected by a trawling cruise of the R/V ARAR in August and December 2009. The concentrations of toxic metals varied between Pb, 3.23-14.4; Cd, <0.01-2.14; Hg, 0.01-0.18 and As, 0.01-0.21 [Formula: see text]g g(-1) dry wt. Pb levels in the Marmara Sea were found to be higher than the critical limits set by the both Turkish Ministry of Environment for Aquatic Products (1 μg g(-1) wet wt.) and European countries (2.0 μg g(-1), UNEP 1985). In contrast, As and Hg levels were found to be lower than the critical limits for two periods. Cd contents of fish from the Marmara Sea were also comparable to or slightly lower than contents of fish from the Southern Black Sea Shelf. The results of organochlorine residues ranged between total HCH, <0.05 and 99 ng g(-1); endrin, <0.001 and 381 ng g(-1); alpha-endosulphan, <0.05 and 90 ng g(-1); beta-endosulphan, <0.05 and 15.3 ng g(-1); o,p DDE, 3.5 and 52.4 ng g(-1); p,p DDE, 7.4 and 139 ng g(-1); o,p DDD, 1.5 and 90.2 ng g(-1) and p,p DDD, 2.7 and 86 ng g(-1) wet weight. The rivers for the distribution of organochlorine levels in the Marmara Sea ordered from highest to lowest as Dil R. > Susurluk R. > Biga R. > G?nen R. The high levels of o,p and p,p DDE, and o,p and p,p DDD compounds, which are metabolites of DDT, indicate its illegal use. Toxic metal and organochlorine residue levels of fish are significantly higher than levels from the Mediterranean Sea.  相似文献   
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Bulking of activated sludge is a world-widely prevalent problem and can lead to loss of bio-oxidation, further deterioration of effluent quality, and even to a complete breakdown of the entire treatment process. Most common reasons of bulking are bacterial community changes, especially excessive growth of filamentous bacteria or excess of biopolymers on surface of non-filamentous microbes. Because of complex nature of the bulking phenomenon, the successful bulking control strategy finding is still a very important need awaiting new options and advices. The repetitive extragenic palindromic PCR (REP-PCR) fingerprinting method has been applied to distinguish bacterial community in non-bulking and bulking activated sludge. The characteristic REP-PCR fingerprinting patterns, using the Ward??s clustering method, have been analyzed to determine homology/similarity relation between particular non-bulking and bulking sludge sampling. The received clustering results were in high concordance with activated sludge typing done based on physicochemical sludge analysis. The choice and application of molecular typing method in sludge analysis will depend upon the needs, skill level, and resources of the laboratory. The proposed REP-PCR method and statistical analysis of fingerprinting patterns seems to be simple, rapid, and effective methods to show differences between population in non-bulking and bulking activated sludge. It is easy to implement, and it may be useful for routinely activated sludge monitoring as well as may be helpful in early detection of bulking process.  相似文献   
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Noise pollution is a common health problem for developing countries. Especially highways and airports lead to noise pollution in different levels and in many frequencies. In this study, we focused on the effect of noise pollution in airports. This work aimed measurements of noise pollution levels in Van Ferit Melen (VFM) airport and effect of noise pollution over the immunoglobulin A, G, and M changes among VFM airport workers in Turkey. It was seen that apron and terminal workers were exposed to high noise (>80 dB(A)) without any protective precautions. Noise-induced temporary threshold shifts and noise-induced permanent threshold shifts were detected between the apron workers (p?<?0.001) and terminal workers (p?<?0.005). IgA values of apron terminal and control group workers were approximately the same in the morning and increased in a linear manner during the day. This increase was statistically significant (p?<?0.001). IgG and IgM values of apron, terminal, and control group workers were approximately same in the morning. Apron and terminal workers IgG and IgM levels were increased until noon and then decreased until evening as compare to control group, but these changes were not statically significant (p?>?0.05). These findings suggested that the noise pollution in the VFM airport could lead to hearing loss and changes in blood serum immunoglobulin levels of airport workers. Blood serum immunoglobulin changes might be due to vibrational effects of noise pollution. Airport workers should apply protective precautions against effect of noise pollution in the VFM airport.  相似文献   
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Untersuchungen anMyriophyllum verticillatum, Potamogeton natans undNymphaea alba in Seen unterschiedlicher Trophiestufen best?tigen, da? in humin- und fulvo-s?urereichen Seen auch bei erh?htem Schwermetallangebot bei einer Reihe von metallen niedrigere Biokonzentrationsfaktoren als in huminstoffarmen Seen zu verzeichnen sind.  相似文献   
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