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Результаты 1351-1360 из 4,042
Comparison of heavy metal contamination during the last decade along the coastal sediment of Pakistan: Multiple pollution indices approach Полный текст
2016
Saher, Noor Us | Siddiqui, Asmat Saleem
Heavy metals concentrations (Fe, Cu, Zn, Ni, Cr, Co, Pb, and Cd) were scrutinized during two monitoring years (2001 and 2011) in the coastal sediment of Pakistan. The status of metal contamination in coastal sediment was interpreted using sediment quality guidelines, and single and combined metal pollution indices. Ni, Cr, and Cd were recognized for their significant (p<0.05) intensification in the sediment during the last decade. Sediment quality guidelines recognized the frequent adverse biological effect of Ni and the occasional adverse biological effect of Cu, Cr, Pb and Cd. Single metal pollution indices (Igeo, EF, CF, and ER) revealed that sediment pollution is predominantly caused by Pb and Cd. Low to moderate contamination was appraised along the coast by multi-metal pollution indices (CD and PERI). Correlation study specifies that heavy metals were presented diverse affiliations and carriers for distribution in the sediment during the last decade.
Показать больше [+] Меньше [-]First comprehensive screening of lipophilic organic contaminants in surface waters of the megacity Jakarta, Indonesia Полный текст
2016
Dsikowitzky, L. | Sträter, M. | Dwiyitno, | Ariyani, F. | Irianto, H.E. | Schwarzbauer, J.
Jakarta is an Indonesian coastal megacity with over 10 million inhabitants. The rivers flowing through the city receive enormous amounts of untreated wastewaters and discharge their pollutant loads into Jakarta Bay. We utilized a screening approach to identify those site-specific compounds that represent the major contamination of the cities' water resources, and detected a total number of 71 organic contaminants in Jakarta river water samples. Especially contaminants originating from municipal wastewater discharges were detected in high concentrations, including flame retardants, personal care products and pharmaceutical drugs.A flame retardant, a synthetic fragrance and caffeine were used as marker compounds to trace the riverine transport of municipal wastewaters into Jakarta Bay. These markers are also appropriate to trace municipal wastewater discharges to other tropical coastal ecosystems. This application is in particular useful to evaluate wastewater inputs from land-based sources to habitats which are sensitive to changing water quality, like coral reefs.
Показать больше [+] Меньше [-]Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in sediments from Khuzestan province, Iran Полный текст
2016
Lübeck, Josephine S. | Poulsen, Kristoffer G. | Knudsen, Sofie B. | Soleimani, Mohsen | Furbo, Søren | Tomasi, Giorgio | Christensen, Jan H.
Khuzestan, Iran is heavily industrialised with petrochemical and refinery companies. Herein, sediment and soil samples were collected from Hendijan coast, Khore Mosa and Arvandroud River. The CHEMSIC (CHEmometric analysis of Selected Ion Chromatograms) method was used to assign the main sources of polycyclic aromatic hydrocarbon (PAH) pollution. A four-component principal component analysis (PCA) model was obtained. While principal component 1 (PC1) was related to the total concentration of PAHs, the remaining PCs described three distinct sources: PC2 and PC3 collectively differentiate between weathered petrogenic and pyrogenic, and PC4 is indicative for a diagenetic input. The sources of PAHs in the Arvandroud River were mainly relatively fresh oil with some samples corresponding to a weathered oil input. Further, perylene (indicator for diagenetic source) was identified. Samples from Khore Mosa revealed a mixture with high proportions of high-molecular-weight PAHs, indicating a pyrogenic/weathered petrogenic source. Samples from Hendijan coast contained low relative concentrations of PAHs, thus only little information on pollution sources.
Показать больше [+] Меньше [-]Risk assessment for marine spills along European coastlines Полный текст
2016
Fernández-Macho, Javier
A marine-spill risk index is proposed to measure and compare the relative vulnerability of coastal regions to marine spills in European waters. It is applied to 301 spills in European waters between 1970 and 2014 for 429 Eurostat territorial units and 156 regions in Europe's coasts. The results show a high heterogeneity among European coastal regions with areas, predominantly on the Atlantic coast, with high marine-spill risks. In particular, UK coasts are markedly affected as there are only five non-British coastal territories within the first 25 territorial units most at risk from marine spills. Across countries, European Atlantic countries face highest risks versus coastal countries on other European waters that are relatively safer. The index also shows a tendency of sea currents to have positive dispersal effects leading to smaller risks rather than otherwise. The index may help to design protection policies and reduce the vulnerability of sensitive resources.
Показать больше [+] Меньше [-]Impact of metal pollution on shrimp Crangon affinis by NMR-based metabolomics Полный текст
2016
Ji, Chenglong | Yu, Deliang | Wang, Qing | Li, Fei | Zhao, Jianmin | Wu, Huifeng
Both cadmium and arsenic are the important metal/metalloid pollutants in the Bohai Sea. In this work, we sampled the dominant species, shrimp Crangon affinis, from three sites, the Middle of the Bohai Sea (MBS), the Yellow River Estuary (YRE) and the Laizhou Bay (LZB) along the Bohai Sea. The concentrations of metals/metalloids in shrimps C. affinis indicated that the YRE site was polluted by Cd and Pb, while the LZB site was contaminated by As. The metabolic differences between shrimps C. affinis from the reference site (MBS) and metal-pollution sites (YRE and LZB) were characterized using NMR-based metabolomics. Results indicated that the metal pollutions in YRE and LZB induced disturbances in osmotic regulation and energy metabolism via different metabolic pathways. In addition, a combination of alanine and arginine might be the biomarker of Cd contamination, while BCAAs and tyrosine could be the biomarkers of arsenic contamination in C. affinis.
Показать больше [+] Меньше [-]Isolation, identification and diesel-oil biodegradation capacities of indigenous hydrocarbon-degrading strains of Cellulosimicrobium cellulans and Acinetobacter baumannii from tarball at Terengganu beach, Malaysia Полный текст
2016
Nkem, Bruno Martins | Halimoon, Normala | Fatimah Md. Yusoff, | Johari, Wan Lufti Wan | Zakaria, Mohamad Pauzi | Medipally, Srikanth Reddy | Kannan, Narayanan
In this study, we isolated two indigenous hydrocarbon-degrading bacteria from tarball found in Rhu Sepuluh beach, Terengganu, Malaysia. These bacteria were identified based on their physiological characteristic and 16S rRNA gene sequence analysis, and they showed 99% similarity with Cellulosimicrobium cellulans DSM 43879 and Acinetobacter baumannii ATCC 19606 respectively. Their hydrocarbon-degrading capabilities were tested using diesel-oil as sole carbon source. Results analysed using GC–MS, showed diesel-oil alkanes were degraded an average 64.4% by C. cellulans and 58.1% by A. baumannii with medium optical density reaching 0.967 (C. cellulans) and 1.515 (A. baumannii) in minimal salt media at 32°C for 10days. Individual diesel-oil alkanes were degraded between 10%–95.4% by C. cellulans and 0.2%–95.9% by A. baumannii. Both strains utilized diesel-oil for growth. The study suggests both strains are part of indigenous hydrocarbon-degrading bacteria in tarball with potential for bioremediation of oil-polluted marine environment.
Показать больше [+] Меньше [-]Water flux management and phytoplankton communities in a Mediterranean coastal lagoon. Part II: Mixotrophy of dinoflagellates as an adaptive strategy? Полный текст
2016
Cecchi, P. | Garrido, M. | Collos, Y. | Pasqualini, V.
Dinoflagellate proliferation is common in coastal waters, and trophic strategies are often advanced to explain the success of these organisms. The Biguglia lagoon is a Mediterranean brackish ecosystem where eutrophication has long been an issue, and where dominance of dinoflagellates has persisted for several years. Monthly monitoring of fluorescence-based properties of phytoplankton communities carried out in 2010 suggested that photosynthesis alone could not support the observed situation all year round. Contrasting food webs developed depending on the hydrological season, with a gradual shift from autotrophy to heterotrophy. Progressively, microphytoplankton assemblages became unequivocally dominated by a Prorocentrum minimum bloom, which exhibited very weak effective photosynthetic performance, whereas paradoxically its theoretical capacities remained fully operational. Different environmental hypotheses explaining this discrepancy were examined, but rejected. We conclude that P. minimum bloom persistence is sustained by mixotrophic strategies, with complex compromises between phototrophy and phagotrophy, as evidenced by fluorescence-based observations.
Показать больше [+] Меньше [-]The assessment of airborne bacterial and fungal contamination emitted by a municipal landfill site in Northern Poland Полный текст
2016
Breza-Boruta, B.
Airborne bacteria and fungi are important biological components of bioaerosol and play an important role in the conservation environmental. A microbiological study on bioaerosoles was carried out at the Municipal Waste Utilization Plant in Northern Poland and at points located beyond the facility at the distance of 150, 450, 1000 and 1250 m. The highest emission of bioaerosol occurred in the area of the waste landfill site and during compost pile turning. The total number of mesophilic bacteria, filamentous fungi and actinomycetes reached the values up to 104 CFU/m3. Strong air contamination with mannitol-positive and mannitol-negative staphylococci occurred remarkably more frequently in the area of the test facility than in the points beyond it. The number of indicator bacteria of Pseudomonas fluorescens was quite changeable and did not depend on a distance from pollutant emission source. The number of Escherichia coli rods remained at the low level of about 102 CFU/m3, and they were only isolated sporadically in the points beyond the landfill. The highest percentage of bacterial aerosol comprised Gram-positive cocci, and then Gram-positive bacilli. Mycological analyses confirmed the presence in the studied air of fungi with potentially allergic and mycotoxinogenic properties, such as: Aspergillus fumigatus, A. niger, A. terreus, Cladosporium herbarum and the genus Fusarium. The concentration level of microbial bioaerosol several times exceeded the threshold values recommended by the Polish Standards. The factors influenced the concentration of microorganisms in the tested air included the distance of the active landfill, weather conditions and the season.
Показать больше [+] Меньше [-]Evaluation of mobile metals in sediments of Burullus Lagoon, Egypt Полный текст
2016
Khalil, Mona | El-Gharabawy, Suzan
The Burullus Lagoon north Nile Delta of Egypt is a UNESCO-protected area. Recently it has become a sediment sink which led to shrinking in its area and depth accompanying with increasing contaminant levels. In this study we attempt to explore the spatial distribution and their mobility of heavy metals (Zn, Cu, Ni, Cr and Pb) based on 21surface sediment samples recovered from Burullus lagoon basin and nine drains. The risk assessment code of the studied heavy metals can be arranged as Zn>Cu>Pb>Cr>Ni for all the samples collected from the lagoon basin and nine different drains. The heavy metals tend to accumulate in fine sediments and human activities promote the accumulation of contaminated sediments in water courses.
Показать больше [+] Меньше [-]Baseline levels of oxidative stress biomarkers in species from a subtropical estuarine system (Paranaguá Bay, southern Brazil) Полный текст
2016
Sardi, Adriana E. | Renaud, Paul E. | Lana, Paulo da Cunha | Camus, Lionel
Baseline levels of oxidative stress biomarkers in species from a subtropical estuarine system (Paranaguá Bay, southern Brazil) Полный текст
2016
Sardi, Adriana E. | Renaud, Paul E. | Lana, Paulo da Cunha | Camus, Lionel
Offshore petroleum exploration has increased the risks of oil spills in coastal tropical and subtropical habitats. Monitoring tools are needed to assess and protect environmental health. We determined baseline values of antioxidant biomarkers (CAT, SOD, GPx, GST, MDA) for five ecologically relevant species in a subtropical system in southern Brazil. Regional baseline levels are compared with literature data as a basis to eventually test their efficacy as post-spill monitoring tools. Differences in the antioxidant response among species, contamination, and seasons were tested using univariate and multivariate analyses. The bivalves Anomalocardia flexuosa and Crassostrea rhizophorae and the catfish Genidens genidens emerge as suitable sentinel species. Seasonality is the main factor accounting for biomarkers variability, and not background contamination level. However, interactions between season and contamination level are also significant, indicating that biomarkers respond to complex environmental settings, a fact that needs to be fully understood for designing proper monitoring programs.
Показать больше [+] Меньше [-]Baseline levels of oxidative stress biomarkers in species from a subtropical estuarine system (Paranaguá Bay, southern Brazil) Полный текст
2016
Sardi Sulvarán, Adriana Eva | Renaud, Paul | Lana, Paulo Da Cunha | Camus, Lionel
Link to publishers version: 10.1016/j.marpolbul.2016.08.014 | Offshore petroleum exploration has increased the risks of oil spills in coastal tropical and subtropical habitats. Monitoring tools are needed to assess and protect environmental health. We determined baseline values of antioxidant biomarkers (CAT, SOD, GPx, GST, MDA) for five ecologically relevant species in a subtropical system in southern Brazil. Regional baseline levels are compared with literature data as a basis to eventually test their efficacy as post-spill monitoring tools. Differences in the antioxidant response among species, contamination, and seasons were tested using univariate and multivariate analyses. The bivalves Anomalocardia flexuosa and Crassostrea rhizophorae and the catfish Genidens genidens emerge as suitable sentinel species. Seasonality is the main factor accounting for biomarkers variability, and not background background contamination level. However, interactions between season and contamination level are also significant, indicating that biomarkers respond to complex environmental settings, a fact that needs to be fully understood for designing proper monitoring programs.
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