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Bioaugmentation strategy employing a microbial consortium immobilized in chitosan beads for oil degradation in mesocosm scale
2016
Dellagnezze, B.M. | Vasconcellos, S.P. | Angelim, A.L. | Melo, V.M.M. | Santisi, S. | Cappello, S. | Oliveira, V.M.
A bacterial consortium composed by four metagenomic clones and Bacillus subtilis strain CBMAI 707, all derived from petroleum reservoirs, was entrapped in chitosan beads and evaluated regarding hydrocarbon degradation capability. Experiments were carried out in mesocosm scale (3000L) with seawater artificially polluted with crude oil. At different time intervals, mesocosms were sampled and subjected to GC-FID and microbiological analyses, as total and heterotrophic culturable bacterial abundance (DAPI and CFU count), biological oxygen demand (BOD) and taxonomic diversity (massive sequencing of 16S rRNA genes). The results obtained showed that degradation of n-alkane hydrocarbons was similar between both treatments. However, aromatic compound degradation was more efficient in bioaugmentation treatment, with biodegradation percentages reaching up to 99% in 30days. Community dynamics was different between treatments and the consortium used in the bioaugmentation treatment contributed to a significant increase in aromatic hydrocarbon degradation.
显示更多 [+] 显示较少 [-]Effects of hypoxia caused by mussel farming on benthic foraminifera in semi-closed Gamak Bay, South Korea
2016
Lee, Yeon Gyu | Jeong, Da Un | Lee, Jung Sick | Choi, Yang Ho | Lee, Moon-ok
Seawater monitoring and geochemical and benthic foraminiferal analysis of sediments were conducted to identify the effects of hypoxia created by a mussel farm on benthic foraminifera in a semi-closed bay. Extremely polluted reductive conditions with a high content of organic matter (OM) at >12.0% and oxygen minimum zones (OMZs) with dissolved oxygen (DO) <0.4mg∙L–1 were formed below the mussel farm in the northwest area of Gamak Bay, and gradually diffused toward the south. Highly similar patterns of variation were observed in species diversity, abundance frequency, and benthic foraminiferal assemblage distributed from Elphidium subarcticum–Ammonia beccarii in the northwest area through E. subarcticum–A. beccarii–Trochammina hadai, E. subarcticum–A. beccarii–Elphidiumclavatum, and E. clavatum–Ammonia ketienziensis in the southern area. These phenomena were caused by hydrodynamics in the current water mass. It was thought that E. subarcticum is a bioindicator of organic pollution caused by the mussel farm.
显示更多 [+] 显示较少 [-]Metabolic performance of the coral reef fish Siganus guttatus exposed to combinations of water borne diesel, an anionic surfactant and elevated temperature in Indonesia
2016
Baum, G. | Kegler, P. | Scholz-Böttcher, B.M. | Alfiansah, Y.R. | Abrar, M. | Kunzmann, A.
Jakarta Bay in Indonesia and its offshore island chain, the Thousand Islands, are facing extreme pollution. Surfactants and diesel-borne compounds from sewage and bilge water discharges are common pollutants. However, knowledge of their effects on reef fish physiology is scarce. This study investigated combined and single effects of a) the water accommodated fraction of diesel (WAF-D, determined by ƩEPA polycyclic aromatic hydrocarbons (PAHs)) and b) the surfactant linear alkylbenzene sulfonate (LAS) on metabolic performance of the coral reef fish Siganus guttatus. Responses to combinations of each pollutant with elevated temperature (+3°C) were determined. Short-term exposure to WAF-D led to a significant decrease in standard metabolic rates, while LAS led to an increase. During combined exposure, metabolic depression was observed. Effects of pollutants were not amplified by elevated temperature. This study highlights the need to reduce import of these pollutants and to avoid negative long-term effects on fish health.
显示更多 [+] 显示较少 [-]Local bleaching thresholds established by remote sensing techniques vary among reefs with deviating bleaching patterns during the 2012 event in the Arabian/Persian Gulf
2016
Shuail, Dawood | Wiedenmann, Jörg | D'Angelo, Cecilia | Baird, Andrew H. | Pratchett, Morgan S. | Riegl, Bernhard | Burt, John A. | Petrov, Peter | Amos, Carl
A severe bleaching event affected coral communities off the coast of Abu Dhabi, UAE in August/September, 2012. In Saadiyat and Ras Ghanada reefs ~40% of the corals showed signs of bleaching. In contrast, only 15% of the corals were affected on Delma reef. Bleaching threshold temperatures for these sites were established using remotely sensed sea surface temperature (SST) data recorded by MODIS-Aqua. The calculated threshold temperatures varied between locations (34.48°C, 34.55°C, 35.05°C), resulting in site-specific deviations in the numbers of days during which these thresholds were exceeded. Hence, the less severe bleaching of Delma reef might be explained by the lower relative heat stress experienced by this coral community. However, the dominance of Porites spp. that is associated with the long-term exposure of Delma reef to elevated temperatures, as well as the more pristine setting may have additionally contributed to the higher coral bleaching threshold for this site.
显示更多 [+] 显示较少 [-]The nutrient load from food waste generated onboard ships in the Baltic Sea
2016
Wilewska-Bien, Magda | Granhag, Lena | Andersson, Karin
The combination of the sensitive characteristics of the Baltic Sea and the intense maritime traffic makes the marine environment vulnerable to anthropogenic influences. The theoretical scenario calculated in this study shows that the annually generated food waste onboard ships in traffic in the Baltic Sea contains about 182tonnes of nitrogen and 34tonnes of phosphorus. Today, all food waste generated onboard can be legally discharged into the marine environment at a distance of 12NM from the nearest land. The annual load of nitrogen contained in the food waste corresponds to 52% of load of nitrogen from the ship-generated sewage. Future regulations for sewage discharge in the Baltic Sea will require significant reduction of total nitrogen and phosphorus released. The contribution of nutrients from food waste compared to sewage will therefore be relatively larger in the future, if food waste still can be legally discharged.
显示更多 [+] 显示较少 [-]Digestive enzymatic patterns as possible biomarkers of endocrine disruption in the red mullet (Mullus barbatus): A preliminary investigation
2016
Caruso, Gabriella | De Pasquale, Francesca | Mita, Damiano Gustavo | Micale, Valeria
During two seasonal trawl surveys (April and October, 2012), red mullet specimens were caught from two sites of the northern Sicilian coast (Western Mediterranean), characterized by different degrees of pollution, to assess whether their digestive enzymes could be cost-effective diagnostic tools for endocrine disruption. Pepsin, chymotrypsin, carboxypeptidases A and B, amylase and lipase were measured in the digestive tract of each fish. During both samplings, significant differences in the digestive enzymatic patterns of fish collected from the two sites were found. In April, pepsin and lipase contents were significantly lower in fish from the most impacted site than in those from the reference site. In October, the enzymatic patterns showed trends different from spring, with controversial results for carboxypeptidases A and B and amylase. Pepsin and lipase patterns suggest a detrimental effect played by organic pollutants and the use of these enzymes as possible biomarkers of exposure to endocrine disruptors.
显示更多 [+] 显示较少 [-]Bioindicators as metrics for environmental monitoring of desalination plant discharges
2016
de-la-Ossa-Carretero, J.A. | Del-Pilar-Ruso, Y. | Loya-Fernández, A. | Ferrero-Vicente, L.M. | Marco-Méndez, C. | Martinez-Garcia, E. | Giménez-Casalduero, F. | Sánchez-Lizaso, J.L.
Development of desalination projects requires simple methodologies and tools for cost-effective and environmentally-sensitive management. Sentinel taxa and biotic indices are easily interpreted in the perspective of environment management. Echinoderms are potential sentinel taxon to gauge the impact produced by brine discharge and the BOPA index is considered an effective tool for monitoring different types of impact. Salinity increase due to desalination brine discharge was evaluated in terms of these two indicators. They reflected the environmental impact and recovery after implementation of a mitigation measure. Echinoderms disappeared at the station closest to the discharge during the years with highest salinity and then recovered their abundance after installation of a diffuser reduced the salinity increase. In the same period, BOPA responded due to the decrease in sensitive amphipods and the increase in tolerant polychaete families when salinities rose. Although salinity changes explained most of the observed variability in both indicators, other abiotic parameters were also significant in explaining this variability.
显示更多 [+] 显示较少 [-]Trophic transfer of toxic elements in the estuarine invertebrate and fish food web of Daliao River, Liaodong Bay, China
2016
Guo, Bobo | Jiao, Deqi | Wang, Jing | Lei, Kai | Lin, Chunye
In order to study element accumulation and trophic transfer in the food web, sixteen benthic invertebrate species and nine fish species were collected from the Daliao River estuary for analysis of toxic elements and nitrogen stable isotope in the muscle tissue. The concentrations ranged between 1.44–17.98, 0.01–9.30, 0.17–36.15, 0.7–145.4, 0.01–0.33, 0.14–14.88, 0.10–2.51, 0.02–0.14, and 19.3–221.1mgkg−1 for As, Cd, Cu, Hg, Ni, Pb, Sb, and Zn, respectively. As, Cd, Cu, and Zn were significantly higher in the benthic invertebrates than in fish, whereas Hg and Sb were significantly lower. In addition, the benthic invertebrates were characterized by the highest bioaccumulation factor (BAF) for Cd, whereas the fish were characterized by the highest BAF for Hg. A significant decrease in Cd, Cr, Cu, and Ni levels, and a significant increase in Hg and Sb levels were observed with increasing trophic levels.
显示更多 [+] 显示较少 [-]Combined environmental stress from shrimp farm and dredging releases in a subtropical coastal lagoon (SE Gulf of California)
2016
Cardoso-Mohedano, J.G. | Páez-Osuna, F. | Amezcua-Martínez, F. | Ruiz-Fernández, A.C. | Ramírez-Reséndiz, G. | Sanchez-Cabeza, J.A.
Nutrient pollution causes environmental damages on aquatic ecosystems worldwide. Eutrophication produces impacts in coastal ecosystems, affecting biota and ecosystem services. The Urias coastal lagoon (SE Gulf of California) is a sub-tropical estuary under several environmental pressures such as nutrient inputs from shrimp farm effluents and dredging related to port operations, which can release substances accumulated in sediments. We assessed the water quality impacts caused by these activities and results showed that i) nitrogen was the limiting nutrient, ii) shrimp farm effluents increased particulate organic matter and chlorophyll a in the receiving stations, and iii) dredging activities increased nitrite and reduced dissolved oxygen concentrations. The co-occurrence of the shrimp farm releases and dredging activities was likely the cause of a negative synergistic effect on water quality which mainly decreases dissolved oxygen and increases nitrite concentrations. Coastal zone management should avoid the co-occurrence of these, and likely others, stressors in coastal ecosystems.
显示更多 [+] 显示较少 [-]Effect of phytoplankton biomass in seawater on chemical properties of sea spray aerosols
2016
Park, Jiyeon | Kim, Dohyung | Lee, Kwangyul | Han, Seunghee | Kim, Hyunji | Williams, Leah R. | Joo, Hung Soo | Park, Kihong
This study is to investigate the effect of biological seawater properties on sea spray aerosols (SSA). Concentrations of chlorophyll-a and bacteria were measured at coastal site in Korea in fall and summer seasons. Also, aerosol mass spectrometer (AMS) was used to determine chemical constituents (organics, sulfate, nitrate, ammonium, and chloride) of non-refractory submicrometer aerosols sprayed from seawaters using a bubble bursting system. The average concentration of chlorophyll-a in seawater in fall was 1.75±0.78μg/l, whereas it significantly increased to 5.11±2.16μg/l in summer. It was found that the fraction of organics in the submicrometer SSA was higher in summer (68%) than fall (49%), and that the organic fraction in the SSA increased as the concentration of chlorophyll-a increased in seawater, suggesting that the high phytoplankton biomass in seawater could lead to the enhancement of organic species in the SSA.
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