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1.
Five stations were established in the Fenglin mangrove area of Xiamen, China to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and the numbers of PAH-degrading bacteria in surface sediments. Assessing the biodegradation potential of indigenous microorganisms and isolating the high molecule weight (HMW)-PAH degrading bacteria was also one of the aims of this work. The results showed that the total PAH concentration of sediments was 222.59 ng g(-1) dry weight, whereas the HMW-PAH benzo(a)pyrene (BaP) had the highest concentration among 16 individual PAH compounds. The variation in the numbers of PAH-degrading bacteria was 2.62 x 10(2)-5.67 x 10(4)CFU g(-1) dry weight. The addition of PAHs showed a great influence in increasing the microbial activity in mangrove sediments. A bacterial consortium, which could utilize BaP as the sole source of carbon and energy, and which was isolated from mangrove sediments and enriched in liquid medium for nearly one year degraded 32.8% of BaP after 63 days incubation.  相似文献   

2.
《Marine pollution bulletin》2014,78(1-2):110-117
Sea microlayer (SML) and subsurface water (SSW) samples were collected around Xiamen Island to study the enrichment and partitioning of polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations ranged from 93.43 to 411.05 ng L−1 in the SML and 49.29–279.42 ng L−1 in the SSW. Compared with the results of previous studies before pollution control measurements, PAHs levels decreased significantly. The enrichment factors (EFs) of dissolved and particulate PAHs varied from 0.68 to 2.71 and 0.43–3.56. EFs showed the consistent enrichment trends with sites and exhibited different enrichment characteristics between 2 and 3 ring PAHs and 4 ring PAHs. Furthermore, the much higher concentrations of BaP (strong carcinogenicity) were accompanied by higher EFs in the SML samples from the Western Xiamen Harbour, which together indicated the risk of impacts to the fish eggs that usually float on the SML water after exposure to oil spills and combustion, contributed directly by the port and shipping activities.  相似文献   

3.
Polycyclic aromatic hydrocarbons are ubiquitous pollutants in the environment, and most high molecular weight PAHs cause mutagenic, teratogenic and potentially carcinogenic effects. While several strains have been identified that degrade PAHs, the present study is focused on the degradation of PAHs in a marine environment by a moderately halophilic bacterial consortium. The bacterial consortium was isolated from a mixture of marine water samples collected from seven different sites in Chennai, India. The low molecular weight (LMW) PAHs phenanthrene and fluorine, and the high molecular weight (HMW) PAHs pyrene and benzo(e)pyrene were selected for the degradation study. The consortium metabolized both LMW and HMW PAHs. The consortium was also able to degrade PAHs present in crude oil-contaminated saline wastewater. The bacterial consortium was able to degrade 80% of HMW PAHs and 100% of LMW PAHs in the saline wastewater. The strains present in the consortium were identified as Ochrobactrum sp., Enterobacter cloacae and Stenotrophomonas maltophilia. This study reveals that these bacteria have the potential to degrade different PAHs in saline wastewater.  相似文献   

4.
The distributions of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the aqueous phase, suspended particulate matter (SPM), sediment, and pore water of the Daliao River Estuary in Liaodong Bay, Bohai Sea (China). Total PAH concentrations ranged from 139.16 to 1717.87 ng L−1 in surface water, from 226.57 to 1404.85 ng L−1 dry weight in SPM, from 276.26 to 1606.89 ng g−1 dry weight in sediments, and from 10.20 to 47.27 μg L−1 in pore water. PAH concentrations were at relatively moderate levels in water, SPM, sediment and pore water in comparison with those reported for other estuary and marine systems around the world. Sedimentary PAH concentrations decreased offshore owing to active deposition of laterally-transported river-borne particles. PCA analysis of the possible PAH source suggested petrogenic and pyrolytic PAH inputs in the studied region.  相似文献   

5.
To assess the contamination of polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean coastal environment of Egypt, 26 sediment samples from the coastline, harbours, estuaries and coastal lakes were collected and analyzed. The sediment PAH concentrations of thirty-nine 2-6 ring PAHs ranged from 13.5 to 22,600 ng/g. PAH profiles varied according to the nature of the site and its proximity to sources. Industrialized and urbanized region showed high level of PAHs contamination. In general, the contamination levels of PAHs were similar to those observed in contaminated and slightly contaminated sediments of the Mediterranean Sea. Molecular indices based on ratios of selected PAH concentrations were used to differentiate PAHs from pyrogenic and petrogenic and mixed origins. Good correlations were observed between the petrogenic index, MP/P, A-PAHs/P-PAHs and HMW/LMW. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (ERM-ERL) for evaluation of probable toxic effects on organism.  相似文献   

6.
Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L−1 for ∑16PAH and 5-10 μg L−1 for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g−1for ∑16PAH and 0.01-5.0 μg g−1 for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin.  相似文献   

7.
《Marine pollution bulletin》2012,64(5-12):424-430
Dynamics of microbial community and biodegradation of polycyclic aromatic hydrocarbons (PAHs) in polluted marine sediments, artificially spiked with a mixture of PAHs (fluorene, phenanthrene, fluoranthene and pyrene), were examined for a period of 60 days. Microbial communities were characterised by bacterial counts, ester-linked fatty acid methyl ester (EL-FAME) analysis and denaturing gradient gel electrophoresis (DGGE). A noted reduction in species diversity occurred only in the high PAH level treatment at onset. Both EL-FAME and DGGE demonstrated a marked shift in microbial community, in all the PAH level treatments, afterwards, with increases in the number of fatty acid degraders, the relative abundance of fatty acid biomarkers for gram-negative bacteria and a decrease in species diversity. The shift was also accompanied by the significant decrease in PAH concentrations. By the end of the experiment, diversity indices, based on both approaches, recovered when PAH concentrations declined to their background levels, except in the high PAH level treatment.  相似文献   

8.
This study compared species identity, microplastics, chemical and microbial contamination between consumption mussels and wild type mussels, collected at Belgian department stores and Belgian groynes and quaysides, respectively. Species identification based on genetic analysis showed a high number of Mytilus (M.) edulis compared to M. galloprovincialis and M. edulis/galloprovincialis hybrid mussels. The number of total microplastics varied from 2.6 to 5.1 fibres/10 g of mussel. A higher prevalence of orange fibres at quaysides is related to fisheries activities. Chemical contamination of polycyclic aromatic hydrocarbons and polychlorobiphenyls could be related to industrial activities and water turbidity, with maximum concentrations at the quayside of port Zeebrugge. The inverse was noted for Escherichia coli contamination, which was relatively low at Zeebrugge quayside with a total count of 3.9 × 102 CFU/100 g tissue, due to limited agricultural effluents. Results of this complementary analysis stress the importance of integrated monitoring and quality assessment.  相似文献   

9.
Polycyclic aromatic hydrocarbons (PAHs) were detected in water and sediment samples collected from three mariculture zones in China’s northern Yellow Sea. In these samples, total PAH concentrations ranged from 110.8 ng/L to 997.2 ng/L and 142.2 ng/g dry weight (dw) to 750.2 ng/g dw, respectively. The log KOC values of the various PAH compounds examined in this study increased with the log KOW values, which is consistent with the prediction regarding PAH behavior in the environment. However, these KOC values were lower than the predicted values as a result of the effects of organic matters, which were abundant in the mariculture water. The isomeric ratios of the PAHs in sediment indicated that the source of the PAHs in the mariculture zones were mainly pyrolytic. The TEQcarc values of PAHs ranged from 7 ng TEQ/g dw to 92 ng TEQ/g dw, and only a few samples met the safe criterion with respect to individual PAH concentrations.  相似文献   

10.
The concentrations of 16 individual and total polycyclic aromatic hydrocarbons (∑PAHs) in sediments, roots and leaves of three mangrove swamps in Shenzhen, China, namely Futian, Baguang and Waterlands, were determined. The mean concentration of ∑PAHs in Futian (4480 ng g−1) was significantly higher than that in Baguang (1262 ng g−1) and Waterlands (2711 ng g−1). Among the 16 PAHs, the concentration of naphthalene was the highest. Based on the ratios of phenanthrene/anthracene and fluoranthene/pyrene, PAHs in Futian and Waterlands came from petrogenic and pyrolytic sources, while Baguang was mainly from pyrolytic. More PAHs were accumulated in leaves, as reflected by its higher mean concentration of ∑PAHs (3697 ng g−1) and bioconcentration factor of PAHs (BCF) (>1.5) than that in roots. The BCF values in plants collected from Futian were significantly higher than that from Waterlands. These results indicated that more attention should be paid to the PAH contamination in Futian.  相似文献   

11.
The levels of selected organic markers, including 17 polycyclic aromatic hydrocarbons (PAHs), 16 of which are classified as priority pollutants by the US-EPA and perylene, aliphatic hydrocarbons (total and linear alkanes) and petroleum biomarkers (hopanes and steranes), were measured in suspended particulate matter (SPM) of the Mundaú-Manguaba estuarine-lagoon system (MMELS) in northeastern Brazil and the Paraíba do Sul River (PSR) estuary in southeastern Brazil, both of which are affected by sugarcane agriculture and urbanization. A total of 33 surface water samples of SPM were collected (22 from the MMELS and 11 from the PSR). The ∑16PAH ranged from 221 to 1243 ng g−1 in the MMELS and from 228 to 1814 ng g−1 in the PSR. Hopane and sterane concentrations in the PSR were higher than in the MMELS due to the input from petrogenic sources in PSR. The contributions of higher plants were also observed by n-alkane analyses. The PAH isomeric ratios indicated that the SPM from MMELS showed characteristics of combustion from biomass or petroleum and PSR was associated to petrogenic input, either from combustion or from unburned petroleum. Three sampling sites located near to the sugarcane plant and mouth of the rivers showed higher PAH concentrations and may largely be considered as highly contaminated. However, levels of n-alkanes and petroleum biomarkers in both study areas were relatively low.  相似文献   

12.
Surface sediment from 15 Italian marine protected areas (MPA) were analysed for polycyclic aromatic hydrocarbons (PAHs). The organic carbon percentage was also determined. Total PAH concentrations (ng g−1 d.w.) ranged from 0.71 (Penisola del Sinis) to 1550 (Miramare). Individual PAH analysis showed that three and four rings PAHs were the most frequently detected isomers and accounted for 60-70% of the PAH total concentrations. PAH ratio analysis showed a prevalence of pyrolytic PAH origin at most of the MPAs with exception of Porto Cesareo and Ustica where a petrogenic origin was detected. Results for organic carbon percentages ranged from 0.3% (Capo Rizzuto) to 2% (Punta Campanella). These results are comparable to other Mediterranean marine environments. However, our results shows that some MPAs, such as Miramare, Porto Cesareo, Isola Capo Rizzuto and Punta Campanella, are subject to strong pressure from urban and industrial activities where high PAH levels were detected.  相似文献   

13.
Dynamics of microbial community and biodegradation of polycyclic aromatic hydrocarbons (PAHs) in polluted marine sediments, artificially spiked with a mixture of PAHs (fluorene, phenanthrene, fluoranthene and pyrene), were examined for a period of 60 days. Microbial communities were characterised by bacterial counts, ester-linked fatty acid methyl ester (EL-FAME) analysis and denaturing gradient gel electrophoresis (DGGE). A noted reduction in species diversity occurred only in the high PAH level treatment at onset. Both EL-FAME and DGGE demonstrated a marked shift in microbial community, in all the PAH level treatments, afterwards, with increases in the number of fatty acid degraders, the relative abundance of fatty acid biomarkers for gram-negative bacteria and a decrease in species diversity. The shift was also accompanied by the significant decrease in PAH concentrations. By the end of the experiment, diversity indices, based on both approaches, recovered when PAH concentrations declined to their background levels, except in the high PAH level treatment.  相似文献   

14.
To assess the extent to which Hurricanes Katrina and Rita affected polycyclic aromatic hydrocarbons (PAH) in the Gulf of Mexico (GOM), sediment cores were analyzed in late 2005 from: a shallow shelf, a deeper shelf, and a marsh station. Sediment geochronology, fabric, and geochemistry show that the 2005 storms deposited ∼10 cm of sediment to the surface of a core at 5-12A. Bulk carbon geochemistry and PAH isomers in this top layer suggest that the source of sediment to the top portion of core 5-12A was from a relatively more marine area. Particulate PAHs in the marsh core (04 M) appeared unaffected by the storms while sediments in the core from Station 5-1B (deeper shelf) were affected minimally (some possible storm-derived deposition). Substantial amounts of PAH-laden particles may have been displaced from the seabed in shallow areas of the water column in the GOM by these 2005 storms.  相似文献   

15.
Spatial distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the Yangtze Estuary, especially the North Branch, have been fully investigated. PAH concentrations increased with the descending distance from the inner estuary to the adjacent sea, and varied significantly in various estuarine regions. Water currents (e.g., river runoff and ocean current) greatly affected the distribution pattern. In addition, ambient sewage and traffic also contributed to the PAH pollution in the estuary. In the adjacent sea, PAH values along the -20m isobath were higher than those along the -10m isobath due to the "marginal filter" phenomenon formed by different water currents. In most sites, PAHs had poor correlations with sediment size, but had positive correlations with total organic carbon. Based on the qualitative and quantitative analysis results, PAH sources were proved to be mainly from a mixture of petroleum combustion, biomass, and coal combustion.  相似文献   

16.
In order to study the impact of produced water (PW) from a North Sea oil field on blue mussels (Mytilus edulis), chemical and biological markers were selected. A laboratory exposure (0.125%, 0.25% and 0.5% of PW) and a field study (6 stations 0.2-2 km from a PW discharge point) were conducted. In the laboratory study, PAH bioaccumulation increased in mussel soft tissue even at the lowest exposure dose. Micronuclei frequency demonstrated a dose-response pattern, whereas lysosomal membrane stability showed tendency towards a dose-response pattern. The same markers were assessed in the field study, biomarker analyses were consistent with the contamination level, as evaluated by mussel polycyclic aromatic hydrocarbons body burden. Overall, obtained results confirmed the value of an ecotoxicological approach for a scientifically sound characterisation of biological effects induced by offshore oilfield operational discharges.  相似文献   

17.
Sixteen sediment samples collected from eight transects in a mangrove swamp of the Jiulong River Estuary, Fujian, China were investigated for their content of polycyclic aromatic hydrocarbons (PAHs) and the biodegradation potential of the indigenous microorganisms. The bacterial community structures in the mangrove sediments and in enrichment cultures were also investigated. The results showed that the total PAHs concentration of mangrove sediments ranged from 280 to 1074 ng g(-1) dry weight, that the PAHs composition pattern in the mangrove sediments was dominated by high molecular weight PAH components (4-6 rings), and that Benzo[ghi]perylene and Indeno[1,2,3-cd]pyrene were the most dominant at different stations. Abundant PAH-degrading bacteria were found in all the stations, the values of phenanthrene-degrading bacteria ranged from 5.85 x 10(4) to 7.80 x 10(5) CFU g(-1) dry weight, fluoranthene-degrading bacteria ranged from 5.25 x 10(4) to 5.79 x 10(5) CFU g(-1) dry weight, pyrene-degrading bacteria ranged from 3.10 x 10(4) to 6.97 x 10(5) CFU g(-1) dry weight and the benzo(a)pyrene-degrading bacteria ranged from 5.25 x 10(4) to 7.26 x 10(5) CFU g(-1) dry weight. DGGE analysis of PCR-amplified 16S rDNA gene fragments confirmed that there was a remarkable shift in the composition of the bacterial community due to the addition of the different model PAH compound phenanthrene (three ring PAH), fluoranthene(four ring PAH), pyrene(four ring PAH) and benzo(a)pyrene(five ring PAH) during enrichment batch culture. Eleven strains were obtained with different morphology and different degradation ability. The presence of common bands for microbial species in the cultures and in the native mangrove sediment DNA indicated that these strains could be potential in situ PAH-degraders.  相似文献   

18.
Sublimation was developed by Alley and Brown (2000) in order to isolate bacterial strains that were capable of degrading water insoluble compounds. In this study, sublimation was modified by the use of nutritional agar plates, instead of mineral salt agar, to isolate phenanthrene-degrading bacteria from a mixed culture that had been enriched under the selective pressure of high phenanthrene content. Five strains were obtained with different morphology and degradation ability. Based on the 16S rDNA sequence, two of them were classified as species of the genus Sphingomonas; the others as species of the genus Burkholderia. Denaturing gradient gel electrophoresis (DGGE) was introduced to detect dynamic changes in the bacterial community during enrichment batch culture, and to determine any correlation between the five isolates and the phenanthrene-degrading consortium. The DGGE profile indicated that these five isolates corresponded to four dominant bands of the consortium. Compared to traditional means of isolation, we concluded that modified sublimation is effective and more convenient.  相似文献   

19.
Sublimation was developed by Alley and Brown (2000) in order to isolate bacterial strains that were capable of degrading water insoluble compounds. In this study, sublimation was modified by the use of nutritional agar plates, instead of mineral salt agar, to isolate phenanthrene-degrading bacteria from a mixed culture that had been enriched under the selective pressure of high phenanthrene content. Five strains were obtained with different morphology and degradation ability. Based on the 16S rDNA sequence, two of them were classified as species of the genus Sphingomonas; the others as species of the genus Burkholderia. Denaturing gradient gel electrophoresis (DGGE) was introduced to detect dynamic changes in the bacterial community during enrichment batch culture, and to determine any correlation between the five isolates and the phenanthrene-degrading consortium. The DGGE profile indicated that these five isolates corresponded to four dominant bands of the consortium. Compared to traditional means of isolation, we concluded that modified sublimation is effective and more convenient.  相似文献   

20.
The concentrations of 24 parental and methylated polycyclic aromatic hydrocarbon (PAH) levels in common limpet (Patella vulgata) were measured in 15 coastal localities of the southern Bay of Biscay and 2 sites per locality for 2 years (spring and autumn of 2004 and 2005, respectively). Although the average concentrations shown a wide variability among the sites and the season, several sites showed a remarkable high concentration (PAHtot>900 ng g−1 d.w.) or medium (300-800 ng g−1 d.w) levels, but in most of the cases the initial high concentrations decreased sharply from one campaign to the following. Moreover, based on ratios of individual isomers concentration, petrogenic and pyrolitic sources were distinguished suggesting more than one source. Finally, based on the results of this work and comparing with previously reported data, it can concluded that limpets can be used as sentinel organisms in coastal environmental monitoring, even when oil spills are involved.  相似文献   

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