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Aberrations in the microbiome of cyanobacteria from a tropical estuary polluted by heavy metals 全文
2020
Jasmin, C. | Anas, Abdulaziz | Singh, Dharmesh | Purohit, H. J. (Hemant J.) | Gireeshkumar, T.R. | Nair, Shanta
The effect of heavy metal pollution on the microbiome of cyanobacteria in Cochin estuary (CE) on the southwest coast of India is reported in the study. Statistically significant difference in heavy metal concentration was observed between water, suspended particulate matter (SPM) and sediment. The Zn, Cd, Cu, Ni and Cr were 2–6 times higher in the SPM compared with the sediment, while Pb was 10 to 25 times higher. Although nearly 60% of the species diversity of microbiome was common between cyanobacteria enriched from the upstream (S1S) and downstream (S11B), there was a difference in the major groups of heterotrophic bacterial associates. Proteobacteria was the dominant phylum (>80%) in S1S, while it was second only (27.5%) after Planctomycetes (37.4%) in S11B. The results of the current study indicate that the pollution can influence an ecosystem at the micro-niche level.
显示更多 [+] 显示较少 [-]Assessment of heavy metal contamination in surface sediments in the western Taiwan Strait 全文
2020
The concentrations of the heavy metals Cu, Pb, Zn, As, Cr, Co, and Ni of a total of 187 surface sediment samples collected from the western Taiwan Strait were analyzed. The distribution characteristics and degree of contamination of these elements were investigated. The mean concentrations of Cu, Pb, Zn, As, Cr, Co, and Ni in the surface sediments of the study area were 10.2 mg/kg, 18.3 mg/kg, 51.7 mg/kg, 7.5 mg/kg, 38.7 mg/kg, 8.0 mg/kg, and 16.5 mg/kg, respectively. The heavy metals in the study area were mainly from natural sources. The regional pollution load index (PLIzone) was 0.64, indicating that there was no contamination, and an area with a relatively high PLIzone was found in the northern part of the study area. Furthermore, the impacts of the rapid development of Fujian's marine economy on the marine environment in the past decade should be further compared and analyzed.
显示更多 [+] 显示较少 [-]Composition, content, source, and risk assessment of PAHs in intertidal sediment in Shilaoren Bay, Qingdao, China 全文
2020
Intertidal sediment samples from Shilaoren Bay, Qingdao, China, were collected to determine the concentrations and compositions of 16 polycyclic aromatic hydrocarbons (PAHs). The sources of PAHs were analyzed, and risk assessment was performed. Results show that the pollution level of PAHs in the investigated area was low. The majority of PAHs are four-ring PAHs. The PAHs in this region were mainly derived from combustion sources, including the incomplete combustion of petroleum, coal, and biomass, such as vegetation, which were affected to some extent by petroleum sources. The highest concentration of PAHs in all sampling sites was lower than that of effects range low, and the mean effects range median quotient was low. Therefore, the PAHs in the study area did not have toxic and side effects on the ecological environment, and ecological risk was low.
显示更多 [+] 显示较少 [-]Effects of heavy metal pollution on germination and early seedling growth in native and invasive Spartina cordgrasses 全文
2020
Seed germination and seedling establishment are the stages most sensitive to abiotic stress in the plant life cycle. We analyzed the effects of copper, zinc and nickel on seed germination and early seedling growth of native Spartina maritima and invasive S. densiflora from polluted and non-polluted estuaries. Germination percentages for either species were not affected by any metal at any tested concentration (up to 2000 μM). However, the increase in metal concentration had negative effects on S. densiflora seedlings. The primary effect was on radicle development, representing initial seedling emergence. Spartina densiflora seedlings emerging from seeds from Tinto Estuary, characterized by high bioavailable metal loads, showed higher tolerance to metals than those from less polluted Odiel and Piedras Estuaries. Comparing our results to metal concentrations in the field, we expect S. densiflora seedling development would be negatively impacted in the most metal-polluted areas in Odiel and Tinto Estuaries.
显示更多 [+] 显示较少 [-]Investigation of heavy metals in the ballast water of ship tanks after and before the implementation of the ballast water convention: Bushehr Port, Persian Gulf 全文
2020
In this study, the amount of heavy metals such as Ni, Cd, Pb and Cu and some physiochemical factors including pH, temperature and total organic carbon (TOC) in the ballast water of the ships entering the Bushehr Port were measured for two years (cold and hot seasons) before and after the ballast water convention was enforced. The mean concentrations of Ni, Cd, Pb and Cu, before and after implementation of the convention were 46.55, 3.93, 5.36, 58.83 and 26.41, 2.12, 2.59, 23.54 ppb. It became clear that the concentrations of heavy metals after the implementation of the convention was lower in comparison and there was a significant difference (p < .05). It seems that continuous monitoring of the quality of the ballast water and determination of locations free of pollution and contamination in the Persian Gulf are necessary for ships that intend to exchange their ballast water in this Gulf.
显示更多 [+] 显示较少 [-]Microplastic fragment and fiber contamination of beach sediments from selected sites in Virginia and North Carolina, USA 全文
2020
(Nora),
Microplastic particles (<5 mm) constitute a growing pollution problem within coastal environments. This study investigated the microplastic presence of estuarine and barrier island beaches in the states of Virginia and North Carolina, USA. Seventeen sediment cores were collected at four study sites and initially tested for microplastic presence by pyrolysis-gas chromatography–mass spectrometry. For the extraction, microplastic particles were first separated from the sediment using a high-density cesium chloride solution (1.88 g/mL). In a second step, an oil extraction collected the remaining microplastic particles of higher densities. Under the light microscope, the extracted microplastic particles were classified based on their morphologies into fragments and fibers. Raman microspectroscopy chemically identified a subset of microplastic particles as polypropylene, polyethylene terephthalate, poly(4-vinylbiphenyl), polystyrene, polyethylene, and nylon. The results show a concentration of microplastic particles (1410 ± 810 per kg of dry sediment) even in protected and ostensibly unpolluted estuarine and beach sediments of Virginia and North Carolina.
显示更多 [+] 显示较少 [-]Evaluation of accelerated biodegradation of oil-SPM aggregates (OSAs) 全文
2020
Leoncio, Lua | de Almeida, Marcos | Silva, Márcio | Oliveira, Olívia M.C. | Moreira, Ícaro T.A. | Lima, Danúsia Ferreira
The studies of the formation of oil-Suspended Particulate Matter (SPM) aggregates (OSAs) have advanced significantly in the scientific community, however there is a need to accelerate oil biodegradation that was dispersed by the formation of OSAs. The present research presents a pioneering character regarding the addition of nutrients as biostimulus for autochthonous hydrocarboclastic bacteria in the biodegradation of Total Petroleum Hydrocarbons (TPH) dispersed by the formation of OSAs. Water aliquots were taken over 60 days from eight bioreactors to perform ionic species analysis, pH, salinity and temperature monitoring, liquid/liquid extraction, serial dilution methodology and filter membrane. TPH quantification was performed on the gas chromatograph with a flame ionisation detector (GC-FID). The addition of nutrients contributed positively to the rate and extent of biodegradation of TPH in association with field-collected SPM. The best result found was with the lowest nutrient concentration (Bio 1) with an average of 98.65% of TPH reduction.
显示更多 [+] 显示较少 [-]Ontogenic and seasonal variations of metal content in a small pelagic fish (Trachurus picturatus) in northwestern African waters 全文
2020
Lozano-Bilbao, Enrique | Lozano, Gonzalo | Jiménez, Sebastián | Jurado-Ruzafa, Alba | Hardisson, Arturo | Rubio, Carmen | Weller, Dailos González | Paz, Soraya | Gutiérrez, Ángel J.
Ontogenic and seasonal variations of metal content in a small pelagic fish (Trachurus picturatus) in northwestern African waters 全文
2020
Lozano-Bilbao, Enrique | Lozano, Gonzalo | Jiménez, Sebastián | Jurado-Ruzafa, Alba | Hardisson, Arturo | Rubio, Carmen | Weller, Dailos González | Paz, Soraya | Gutiérrez, Ángel J.
Marine organisms are exposed to great changes induced by human beings due, among others, to discharges into the oceans, increasing marine pollution. For this study, 294 specimens of Trachurus picturatus from the Canary Islands were analyzed during a period of 2 years. The concentration of 11 anthropic metals and trace elements was determined in each individual using the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. Statistical analyses were carried out considering the following factors: oceanographic season, maturity of the gonads, size of the specimens, season. Immature specimens had higher concentration in more metals than the mature specimens. This fact may be due to the fact that these specimens require a much higher metabolic rate due to their growth and do not detoxify like mature specimens.
显示更多 [+] 显示较少 [-]Ontogenic and seasonal variations of metal contents in a small pelagic fish (Trachurus picturatus) in northwestern African waters 全文
2020
Lozano-Bilbao, Enrique | Lozano, G. | Jiménez, Sebastián | Jurado-Ruzafa, Alba | Hardisson, Arturo | Rubio, C. | González Weller, Dalios | Paz, S. | Gutiérrez, Á.J.
Marine organisms are exposed to great changes induced by human beings due, among others, to discharges into the oceans, increasing marine pollution. For this study, 294 specimens of Trachurus picturatus from the Canary Islands were analyzed during a period of 2 years. The concentration of 11 anthropic metals and trace elements was determined in each individual using the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. Statistical analyses were carried out considering the following factors: oceanographic season, maturity of the gonads, size of the specimens, season. Immature specimens had higher concentration in more metals than the mature specimens. This fact may be due to the fact that these specimens require a much higher metabolic rate due to their growth and do not detoxify like mature specimens. | Sí
显示更多 [+] 显示较少 [-]Current State-of-the-Art and New Directions in Strategic Environmental Noise Mapping 全文
2020
Murphy, Enda | Faulkner, Jon Paul | Douglas, Owen
Environmental noise mapping has the potential to act as a powerful resource for policymakers as a decision support tool for the mitigation of the negative effects of environmental noise pollution and its impact on public health. The aim of this paper is to review current state-of-the-art developments in how the strategic noise mapping (SNM) process has progressed at the EU level since the introduction of the Environmental Noise Directive (END) in 2002. Reviewing such developments is important because of the relevance of SNM to public health. In this regard, the development of a new standardized noise calculation method (i.e. CNOSSOS-EU) is also considered, as well as the future potential for noise mapping and the impact of technology on the development of noise pollution assessment.
显示更多 [+] 显示较少 [-]On the transport and landfall of marine oil spills, laboratory and field observations 全文
2020
Novelli, Guillaume | Guigand, Cédric M. | Boufadel, Michel C. | Özgökmen, Tamay M.
The dynamics of crude oil and different surface ocean drifters were compared to study the physical processes that govern the transport and landfall of marine oil spills. In a wave-tank experiment, drifters with drogue did not follow oil slicks. However, patches of undrogued drifters and thin bamboo plates did spread at the same rate and in the same direction as the crude oil slicks. Then, the trajectories of the Deepwater Horizon oil spill and 1300 drifters released near the spill source were investigated. Undrogued drifters were transported twice as fast as drogued drifters across the isobaths. 25% of the undrogued drifters landed, versus about 5% of the drogued ones, for the most part, on the same coastline locations where oil was found after Deepwater Horizon. Results highlight the importance of near surface gradients in controlling the cross-shelf transport and landing of surface material on the Gulf of Mexico's northern shores.
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