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51.
Liu Y Peng Z Wei G Chen T Sun W He J Liu G Chou CL Shen CC 《Marine environmental research》2011,71(1):62-69
Here we present interannual rare earth element (REE) records spanning the last two decades of the 20th century in two living Porites corals, collected from Longwan Bay, close to the estuarine zones off Wanquan River of Hainan Island and Hong Kong off the Pearl River Delta of Guangdong Province in the northern South China Sea. The results show that both coral REE contents (0.5-40 ng g?1 in Longwan Bay and 2-250 ng g?1 in Hong Kong for La-Lu) are characterized with a declining trend, which are significantly negative correlated with regional sea-level rise (9.4 mm a?1) from 1981 to 1996 in Longwan Bay, 13.7 mm a?1 from 1991 to 2001 in Hong Kong). The REE features are proposed to be resulted from seawater intrusion into the estuaries in response to contemporary sea-level rise. However, the tendency for the coral Er/Nd time series at Hong Kong site is absent and there is no significant relation between Er/Nd and total REEs as found for the coral at Longwan Bay site. The observations are likely attributed to changes of the water discharge and sediment load of Pearl River, which have been significantly affected by intense human activities, such as the construction of dams/reservoirs and riverbed sediment mining, in past decades. The riverine sediment load/discharge ratio of the Pearl River decreased sharply with a rate of 0.02 kg m?3 a?1, which could make significant contribution to the declining trend of coral REE. We propose that coastal corals in Longwan Bay and similar unexplored sites with little influences of river discharge and anthropogenic disruption are ideal candidates to investigate the influence of sea-level change on seawater/coral REE. 相似文献
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Chou CL Paon LA Moffatt JD Buzeta MI Fenton D Rutherford RJ 《Marine pollution bulletin》2004,48(9-10):884-893
The Musquash Estuary, one of the last ecologically intact estuaries in New Brunswick, has been designated an area of interest for a marine protected area (MPA) under the Oceans Act. The area has been assessed for contaminant background levels as required for establishing MPA environmental quality. American lobster (Homarus americanus), blue mussel (Mytilus edulis) and sediments were collected for assessing contaminant levels and distribution in the harbour. Levels of contaminants from the indicator species and the abiotic component have shown: (1) two extremes of high and low Cu and Ag in lobster from the area; and (2) lower metal levels in inner Musquash Harbour sediments and mussels than in those from the harbour mouth. These suggest that deposition of contaminants into the Musquash MPA site was due to transport of contaminants by coastal currents from upstream coastal industrial activities. This reverse trend with higher contaminant levels in the biotic and abiotic components in the outer harbour than in the inner harbour differs from a contaminated harbour and suggests that a contaminant exclusion zone should be considered for controlling contamination from nearby coastal and estuarine industrial sites to protect the sensitive habitats within the marine protected area. 相似文献
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Sediment samples collected from Kaohsiung Harbor (Taiwan) were analyzed for 15 priority polycyclic aromatic hydrocarbons (PAHs) and 118 individual polychlorinated biphenyl (PCB) congeners in various particle size fractions and two density fractions. The PAHs in the low density fraction were a much more sensitive and effective indicator of the PAH source than those in the sediment as a whole. Hierarchical cluster analysis of PAH analytes in the low density sediments revealed significant differences in compositional patterns between locations and among size fractions. In the sediment samples from both study sites, the low density fraction particles had up to 155 and 150 times higher concentrations of PAHs and PCBs, respectively, than those in the corresponding high density fractions. In addition, the total toxic benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzodioxin (TCDD, dioxin) equivalents in the sediment low density fractions were much higher (up to 170 and 273 times, respectively) than the corresponding high density fractions. 相似文献
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In the present study, the risk to humans by consuming European sea bass (Dicentrarchus labrax), captured at three sites along a Hg contamination gradient, was evaluated by comparing muscle and kidney total Hg (T-Hg) levels with the European regulations for marketed fish. Moreover, T-Hg and organic Hg (O-Hg) levels in muscle were compared with the Provisional Tolerable Weekly Intake (PTWI) and the Reference Dose (RfD). Although T-Hg levels in muscle were below the European value allowable for marketed fish, kidney’s levels were higher than the set value, stressing the importance of redefining the concept of edible tissue and which tissues should be considered. Mercury weekly ingestion in the contaminated areas was higher than the PTWI, and O-Hg daily ingestion rates were higher than the RfD in all sampling sites. Thus, populations consuming sea bass from the contaminated sites may be at risk, with particular relevance for children and pregnant women. 相似文献
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Typhoon Morakot pounded Taiwan in 2009 with record-breaking rainfall, washing an unprecedented amount of driftwood into the sea that was partially deposited at the coastal areas. According to the satellite imagery analysis, more than three million trees fell and were washed away to occupy 83.2% of the Taiwanese coastline, including 52 fishing harbors. The amount cleaned-up was only 1/7 of the total coastal driftwood. It was found that the amount of coastal driftwood is not only related to the amount of precipitation but is also related to the distance from the location of the landslide to the river mouth and to the landslide area. The amount of accumulated coastal driftwood demonstrated log-profile declines with increasing distance to the river mouth. Nearshore current and wave motion are the critical factors for driftwood deposition. Much of the driftwood washed into the sea harmed the tourism and fishing industries, endangered navigation and oceanic activities, and impacted the marine environment and ecosystem. 相似文献
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论述了二道沟金矿床不同矿脉黄铁矿形态、成分、热电性及石英成分、晶胞参数、热发光等方面的找矿标型特征.并且可作为评价地质体含矿性。判断矿体剥蚀程度以及预测金矿床深部找矿远景的指示标志.为寻找和评价二遭沟式金矿提供找矿矿物学依据。 相似文献