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Seawater quality criteria derivation and ecological risk assessment for oil pollution in China 全文
2019
Zhenguang, Yan | Pan, Jinfen | Gao, Fu | An, Zhe | Liu, Huifang | Huang, Yi | Wang, Xiaobing
The establishment of water quality criteria (WQC) for oil pollutants is the basis for ecological risk assessment of marine oil pollution. Ecotoxicity data of oil pollutants to marine organisms in China were collected and toxicity test of oil to nine Chinese marine organisms were performed. Based on the WQC guidelines of the United States, the sea WQC of oil pollutants in China were studied. Then, the ecological risk of oil in 7 sea areas of China was assessed. Results showed that the long-term and short-term criteria of oil pollutants in China are 7.3 μg/L and 36 μg/L, respectively. Except for Qinhuangdao and Xiamen sea areas, the highest oil concentration in the other five sea areas exceeded the long-term WQC by >10 times, and the highest oil concentration in the Pearl River Estuary exceeded the long-term WQC by >100 times, indicating serious ecological risk.
显示更多 [+] 显示较少 [-]Stable isotopes and geochemical indicators in marine sediments as proxies for anthropogenic impact: A baseline for coastal environments of central Chile (33°S) 全文
2019
Pastene, Marion | Quiroga, Eduardo | Hurtado, Carlos Felipe
Stable isotopes and geochemical proxies (TOC/TN and Chla/TOC) in sediments can be used to distinguish organic matter sources (anthropogenic, terrestrial, or marine). This study aims to characterize organic matter (OM) in superficial sediments from three sectors of central Chile (33°S) that are highly influenced by urban and industrial development. Our results show that a substantial fraction of these OM in Quintero Bay is anthropogenic, from industrial and domestic wastewater sources. In contrast, a mixture of terrestrial and anthropogenic OM dominates the isotopic signal of surface sediments from Concón, derived from non-point industrial and agriculture sources associated with the Aconcagua River basin, while Ritoque exhibited a mixture of different OM sources. However, deposition of allochthonous OM in our study area depends on coastal topography, which influences the local currents and well-ventilated waters, promoting the dispersion and assimilation of OM and thus providing an environment with a high capacity for natural remediation.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons in Pacific herring (Clupea pallasii) embryos exposed to creosote-treated pilings during a piling-removal project in a nearshore marine habitat of Puget Sound 全文
2019
West, James E. | Carey, Andrea J. | Ylitalo, Gina M. | Incardona, John P. | Edmunds, Richard C. | Sloan, Catherine A. | Niewolny, Laurie A. | Lanksbury, Jennifer A. | O'Neill, Sandra M.
We used manually spawned, field-deployed embryos of a common marine fish species, Pacific herring (Clupea pallasii), to evaluate accumulation of polycyclic aromatic hydrocarbons (PAHs) associated with an incomplete creosote-treated piling (CTP) removal project. Embryos near undisturbed 100-year-old CTPs (before removal) accumulated higher PAHs and exhibited higher cyp1a gene expression than embryos from reference areas. Embryos incubated close to CTP debris after CTP removal showed PAHs 90 times higher than reference areas up to a year after CTP removal. cyp1a fold-induction correlated with total embryo PAHs in all three years. Patterns of individual PAH chemicals differed slightly between embryos, wood sampled from CTPs, and passive samplers. This study illustrates the importance of using appropriate techniques and procedures to remove CTPs in aquatic environments to prevent release of toxic chemicals. Of particular concern is that incomplete CTP removal could expose sensitive life stages of fishes to chemicals that may reduce their survival.
显示更多 [+] 显示较少 [-]Radioactive level of coral reefs in the South China Sea 全文
2019
Lin, Wuhui | Yu, Kefu | Wang, Yinghui | Liu, Xinming | Ning, Qiuyun | Huang, Xueyong
In this study, we examined radioactivity simultaneously in surface marine sediments and coral skeletons collected from 12 locations of the fringing and atoll reefs in the South China Sea. Radioactive level declined from the fringing reefs to atoll reefs because of input of terrigenous minerals in the fringing reefs. Radioactivity was higher in coral skeletons than in marine sediments because of the high ²²⁸Ra activity in coral skeletons. Additionally, an abnormally low ²²⁶Ra/²³⁸U activity ratio (<0.1) of marine sediments in coral reefs was attributed to the biological process of active uptake of ²²⁶Ra and ²³⁸U from seawater by coral polyps rather than the ingrowth process in the ²³⁸U-²³⁰Th-²²⁶Ra decay chain. Several radiological indices were evaluated in coral reefs and significantly lower than recommended values. Particularly, the average Raₑq in the atoll reefs was <5% of the world's average of Raₑq. Our results displayed typically radioactive status in coral reefs without close-in fallout of anthropogenic radionuclides.
显示更多 [+] 显示较少 [-]Can the input of biocides and polymeric substances from antifouling paints into the sea be reduced by the use of non-toxic hard coatings? 全文
2019
Watermann, B. | Eklund, B.
Antifouling coatings are used to protect boat hulls from fouling organisms. The paints are designed to release biocides and by this prevent fouling organisms to attach. Until now the simultaneous release of the bulk plastic material has been over-looked. In this study the amount of antifouling paints on ships and leisure boats in Scandinavian countries and Germany has been compared and a calculation of the release of micro plastics has been performed. The result shows that use of a biocide-free hard coating will completely reduce outlet of biocides and the input of polymers will dramatically be reduced from at the most 5% in comparison to traditional paints where the release rate of plastics is estimated to be 70–85%. The advantage for the boat owners will be large since the hard maintenance work will be reduced, release of micro plastics will be low and thus lead to an improved environment.
显示更多 [+] 显示较少 [-]A novel GIS-based tool for predicting coastal litter accumulation and optimising coastal cleanup actions 全文
2019
Haarr, Marthe Larsen | Westerveld, Levi | Fabres, Joan | Iversen, Kriss Rokkan | Busch, Kjersti Eline Tønnessen
Effective site selection is a key component of maximising debris removal during coastal cleanup actions. We tested a GIS-based predictive model to identify marine litter hotspots in Lofoten, Norway based on shoreline gradient and shape. Litter density was recorded at 27 randomly selected locations with 5 transects sampled in each. Shoreline gradient was a limiting factor to litter accumulation when >35%. The curvature of the coastline correlated differently with litter density at different spatial scales. The greatest litter concentrations were in small coves located on larger headlands. A parsimonious model scoring sites on a scale of 1–5 based on shoreline slope and shape had the highest validation success. Sites unlikely to have high litter concentrations were successfully identified and could be avoided. The accuracy of hotspot identifications was more variable, and presumably more parameters influencing litter deposition, such as shoreline aspect relative to prevailing winds, should be incorporated.
显示更多 [+] 显示较少 [-]Persistent organic pollutants in blubber of fin whales (Balaenoptera physalus) from the Southern Ocean 全文
2019
Taniguchi, Satie | Rosa, Luciano Dalla | Colabuono, Fernanda I. | Dalla Rosa, Luciano | Secchi, Eduardo R. | da Silva, Josilene | Maia, Daniela A. | Montone, Rosalinda C.
Persistent organic pollutants (POPs) were analyzed in eighteen blubber samples biopsied from fin whales (Balaenoptera physalus) during the feeding season near the Antarctic Peninsula in the summer of 2013. POP content (in ng g⁻¹ lipid weight) ranged from 46.4 to 708 for polychlorinated biphenyls (∑PCBs), 6.77 to 123 for hexachlorobenzene (HCB), 10.1 to 489 for dichlorodiphenyltrichloroethane and derivatives (∑DDTs), 5.38 to 52.8 for hexachlorocyclohexanes (∑HCH) and <0.40 to 2.54 for polybrominated diphenyl ethers (∑PBDEs). The presence of those compounds in Southern Ocean fin whales is related to long-range transport and their diet based mainly on euphausiids (krill). Their contents were much lower compared to the same species in other locations, especially in the Northern Hemisphere, presumably due to differences in trophic position and the proximity of POP sources and contamination of prey items.
显示更多 [+] 显示较少 [-]Dynamic of small polyethylene microplastics (≤10 μm) in mussel's tissues 全文
2019
Fernández, Beatriz | Albentosa, Marina
Dynamic of small polyethylene microplastics (≤10 μm) in mussel's tissues 全文
2019
Fernández, Beatriz | Albentosa, Marina
MPs' uptake and tissue accumulation were investigated in mussel exposed to a single dose (2.85 mg ind⁻¹, 3 mg l⁻¹) of a heterogeneous mixture of irregularly shaped particles of HDPE (mainly ≤10 μm), followed by a 7 days depuration period. The results showed that mussels efficiently cleared MPs from water during exposure, and that MPs were accumulated in digestive gland and gills during depuration. In digestive gland, the amount and size of the MPs accumulated decreased with time, indicating a slower processing and elimination of small MPs than of larger ones. In gills, MPs' burdens increased with time, the MPs accumulated were the smallest ones, suggesting the translocation of small MPs from the digestive system to the gills. The hazardous potential of the smaller fraction of MPs (≤4 μm) underlined that more focus should be directed towards the accumulation and effects of this fraction of MPs in the marine environment.
显示更多 [+] 显示较少 [-]Dynamic of small polyethylene microplastics (<10 um) in mussel´s tissues 全文
2019
Fernández-Galindo, Beatriz | Albentosa, Marina
MPs' uptake and tissue accumulation were investigated in mussel exposed to a single dose (2.85 mg ind−1, 3 mg l−1) of a heterogeneous mixture of irregularly shaped particles of HDPE (mainly ≤10 μm), followed by a 7 days depuration period. The results showed that mussels efficiently cleared MPs from water during exposure, and that MPs were accumulated in digestive gland and gills during depuration. In digestive gland, the amount and size of the MPs accumulated decreased with time, indicating a slower processing and elimination of small MPs than of larger ones. In gills, MPs' burdens increased with time, the MPs accumulated were the smallest ones, suggesting the translocation of small MPs from the digestive system to the gills. The hazardous potential of the smaller fraction of MPs (≤4 μm) underlined that more focus should be directed towards the accumulation and effects of this fraction of MPs in the marine environment. | Sí
显示更多 [+] 显示较少 [-]Heavy metal contamination status in soil-plant system in the Upper Mersey Estuarine Floodplain, Northwest England 全文
2019
Enya, Osim | Lin, Chuxia | Qin, Junhao
Globally, soil contamination by heavy metals is common in estuarine floodplains. A study was conducted to assess heavy metal contamination in the soil-plant system in Mersey estuarine floodplain, North West England. Representative composite soil samples and plant samples were collected from nine identified land use types across the study area. Various fraction of heavy metals in soils and plant tissue-borne heavy metals were determined. The results show that the study area has elevated concentrations of As, Cr, Cu, Pb and Zn. Heavy metal concentration in soils was generally higher in the lowlying areas than in the upland portions. There was a trend that concentration of heavy metals increased with increasing depth due to de-industrialisation in the upper catchment. The soil contamination resulted in elevated concentration of heavy metals in the grazed plants, which could pose a risk to wild animals, grazing animals and people who consume the grazing animal meat.
显示更多 [+] 显示较少 [-]Conservation and restoration of a keystone species: Understanding the settlement preferences of the European oyster (Ostrea edulis) 全文
2019
Rodriguez-Perez, Ana | James, Mark | Donnan, David W. | Henry, Theodore B. | Møller, Lene Friis | Sanderson, William G.
The European oyster Ostrea edulis is a keystone species that is internationally recognised as ‘threatened and declining’ in the NE Atlantic by OSPAR and several nations have consequently adopted strategies for its conservation and restoration. Understanding the settlement behaviour of O. edulis larvae is crucial to inform these strategies. We compared the efficiency of several treatments in triggering settlement. The most effective settlement occurred with the presence of conspecifics: 100% settled in <23 h. Marine stones with habitat-associated biofilms induced 81% settlement that started after a 45 h delay. Sterile shells and terrestrial stones did not induce more settlement than control treatments. These results indicate that O. edulis larvae are gregarious and finely-tuned to settle in response to cues which are indicative of their adult habitat requirements. The role of chemical cues in mediating settlement, and the importance of this to restoration, are discussed.
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