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991.
Eeva T Ojanen M Räsänen O Lehikoinen E 《Environmental pollution (Barking, Essex : 1987)》2000,109(2):303-309
Great tits (Parus major) are sometimes found to incubate in their nests even though the nests contain no eggs. This phenomenon has been observed in different parts of Europe (Sweden, Finland, UK, Netherlands, Germany) and it has become more common during the 1980s. We analysed the occurrence of empty nests in P. major and in pied flycatcher (Ficedula hypoleuca) in SW Finland from 6-year data collected in a polluted area around a copper smelter which emits large quantities of sulphuric oxides and heavy metals. Among first broods 3.3% of P. major females incubated in empty nests. Incubation on empty nests was not observed in F. hypoleuca, but in this species 2.4% of the nests remained without eggs. In both species empty nests were more common close to the pollution source than farther away. Histopathological analyses in P. major suggest that there are diverse reasons for the incapability of a female to lay. One out of five P. major females captured from incubating in an empty nest had dark cysts in her oviduct. Two P. major females had very scanty medullary bone tissue in their tibiotarsus and tarsometatarsus and one female showed exceptionally high concentrations of lead in her bone tissue. We conclude that air pollutants enhance the number of empty nests especially in F. hypoleuca, but cannot wholly explain the phenomenon in P. major. 相似文献
992.
993.
994.
Regnell O 《Environmental pollution (Barking, Essex : 1987)》1994,84(1):7-13
Radio-labelled mercury, 203HgCl2, was added to water overlying sediment in freshwater model systems. The partitioning of 203Hg between water, sediment and air and the concentration of methyl 203Hg in the water did not differ significantly between systems with a water pH of 5.8+/-0.07 and 6.6+/-0.05. When the systems were made anaerobic and microbial activity was stimulated by the addition of tryptic soybroth (TSB), the level of methyl 203Hg in the water increased by two orders of magnitude. There was also an increase in the concentration of total 203Hg in the water, which was greater than the increase in methyl 203Hg, indicating release of both methyl 203Hg and other 203Hg species from sediment to water. In the systems that were kept aerobic, there was no increase in either total or methyl 203Hg in the water after stimulating the microbial activity with TSB. However, volatilization of 203Hg increased, which was not the case in the anaerobic systems. 相似文献
995.
Photocatalytic degradation of formaldehyde containing wastewater from veterinarian laboratories 总被引:1,自引:0,他引:1
Araña J Martínez Nieto JL Herrera Melián JA Doña Rodríguez JM González Díaz O Pérez Peña J Bergasa O Alvarez C Méndez J 《Chemosphere》2004,55(6):893-904
The photocatalytic destruction of methanol, formaline (mixture of formaldehyde, methanol and water) and formaline wastes from the preservation of vertinarian physiologic samples has been attempted by two different processes, at high concentrations of reagents and by dossification of reagents, varying pH in both. Experiment evolution has been monitored by measuring the organic matter such as TOC and formaldehyde concentrations [H2CO]. Also, methanol and methanol-formaldehyde interactions with the TiO2 surface have been analysed by FTIR spectroscopy. Results indicate that at high concentrations the catalyst surfacial alterations given by methoxy, formates or carbonates, according to the pH of the sample can profoundly affect catalyst behaviour. It has been established that reagent dossification is advantageous for enhancing photonic efficiency as it minimizes the adsorbate presence that hampers the photocatalytic process. 相似文献
996.
Danis B Bustamante P Cotret O Teyssié JL Fowler SW Warnau M 《Environmental pollution (Barking, Essex : 1987)》2005,134(1):113-122
The cuttlefish Sepia officinalis was selected as a model cephalopod to study PCB bioaccumulation via seawater, sediments and food. Newly hatched, juvenile cuttlefish were exposed for 17 days to environmentally realistic concentrations of (14)C-labeled 2,2',4,4',5,5'-hexachlorobiphenyl (PCB#153) (18 ng PCB l(-1) seawater; 30 ng PCB g(-1) dry wt sediments; Artemia salina exposed to 18 ng PCB l(-1) seawater). Accumulation of PCB#153 was followed in three body compartments: digestive gland, cuttlebone and the combined remaining tissues. Results showed that (1) uptake kinetics were source- and body compartment-dependent, (2) for each body compartment, the accumulation was far greater when S. officinalis was exposed via seawater, (3) the cuttlebone accumulated little of the contaminant regardless of the source, and (4) the PCB congener showed a similar distribution pattern among the different body compartments following exposure to contaminated seawater, sediment or food with the lowest concentrations in the cuttlebone and the highest in the remaining tissues. The use of radiotracer techniques allowed delineating PCB kinetics in small whole organisms as well as in their separate tissues. The results underscore the enhanced ability of cephalopods to concentrate organic pollutants such as PCBs, and raise the question of potential risk to their predators in contaminated areas. 相似文献
997.
Borghini F Grimalt JO Sanchez-Hernandez JC Barra R García CJ Focardi S 《Environmental pollution (Barking, Essex : 1987)》2005,136(2):253-266
Semi-volatile organochlorine compounds (OC) were analyzed in remote Andean soils and lake sediments. The sampling sites covered a wide latitudinal gradient from 18 degrees S to 46 degrees S along Chile and an altitudinal gradient (10-4500 m). The concentrations were in the order of background levels, involving absence of major pollution sources in the high mountain areas. Significant correlations were found between log-transformed concentrations of hexachlorobenzene, alpha- and gamma-hexachlorocyclohexane in soils and total organic content (TOC). In addition, TOC-normalized concentrations of the most volatile OC showed a significant linear dependence with air temperature. This good agreement points to temperature as a significant factor for the retention of long range transported OC in remote ecosystems such as the Andean mountains, although other variables should not be totally excluded. The highest concentrations of OCs were achieved in the sites located at highest altitude and lowest temperature of the dataset. 相似文献
998.
Jiang P Lignell DO Kelly KE Lighty JS Sarofim AF Montgomery CJ 《Journal of the Air & Waste Management Association (1995)》2005,55(4):437-445
Over the past several years, numerous studies have linked ambient concentrations of particulate matter (PM) to adverse health effects, and more recent studies have identified PM size and surface area as important factors in determining the health effects of PM. This study contributes to a better understanding of the evolution of particle size distributions in exhaust plumes with unconfined dilution by ambient air. It combines computational fluid dynamics (CFD) with an aerosol dynamics model to examine the effects of different streamlines in an exhaust plume, ambient particle size distributions, and vehicle and wind speed on the particle size distribution in an exhaust plume. CFD was used to calculate the flow field and gas mixing for unconfined dilution of a vehicle exhaust plume, and the calculated dilution ratios were then used as input to the aerosol dynamics simulation. The results of the study show that vehicle speed affected the particle size distribution of an exhaust plume because increasing vehicle speed caused more rapid dilution and inhibited coagulation. Ambient particle size distributions had an effect on the smaller sized particles (approximately 10 nm range under some conditions) and larger sized particles (>2 microm) of the particle size distribution. The ambient air particle size distribution affects the larger sizes of the exhaust plume because vehicle exhaust typically contains few particles larger than 2 microm. Finally, the location of a streamline in the exhaust plume had little effect on the particle size distribution; the particle size distribution along any streamline at a distance x differed by less than 5% from the particle size distributions along any other streamline at distance x. 相似文献
999.
An evaluation of olive-tree bark for the biological monitoring of airborne trace-elements at ground level 总被引:1,自引:0,他引:1
Pacheco AM Barros LI Freitas MC Reis MA Hipólito C Oliveira OR 《Environmental pollution (Barking, Essex : 1987)》2002,120(1):79-86
There is a need to start looking into the possibility of tree bark for biomonitoring. Bark from olive trees (Olea europaea Linn.) has been collected over an area in northwestern Portugal, featuring a blend of rural lands, industrial towns and coastal environments. Samples were analysed through INAA and PIXE for their elemental contents. Results from both techniques were reconciled and then compared with an extensive database on 46 trace elements in Parmelia spp. thalli from the same sites and mostly from the very bark substrates. Distribution-free, nonparametric statistics show that, despite signal magnitude, variation patterns of bark and lichen concentrations follow one another in a most significant way. Selected elements in bark also correlate to a superior extent. As far as this investigation goes, there is no reason whatsoever for discarding bark as an alternative to lower epiphytes. 相似文献
1000.
Haussard M Gaballah I de Donato P Barrès O Mourey A 《Journal of the Air & Waste Management Association (1995)》2001,51(9):1351-1358
This paper explores the possibility of removing hydrocarbons (HCs) and trace elements from synthetic and industrial effluents using treated bark as biosorbent. Coniferous bark was treated either chemically (Tc) or biologically (Tb) to eliminate soluble organic compounds of bark. The removal efficiency (RE) of the HCs from a synthetic oil-water mixture containing spent diesel motor oil exceeds 95% using 2 g/L of treated bark mixed with a synthetic oil-water mixture containing 2 g/L of spent oil. Under these conditions, the retention capacity (RC) was approximately 1 g HC/g dry substrate. The sorption reaction seems to be quasi-instantaneous, and the retention capacity of spent oil on treated bark increases as the temperature augments. This implies that the retention mechanism is related to the capillary action. Results of Fourier transform infrared (FTIR) spectroscopy indicate that spent oil is mainly composed of alkanes. They also suggest that no chemical bonds between Tc and spent oil were established. Measurement of the surface tension of spent oil and the wetting index of the bark suggests that only spent oil will be retained by the substrate. Treatment of an industrial effluent containing 14.4 g/L of total HCs was performed using Tc. It was possible to remove 97% of HCs and retain some trace elements such as Al, Ca, Fe, Mg, S, and so on. 相似文献