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Influence of nutrients pollution on the growth and organic matter output of Ulva prolifera in the southern Yellow Sea, China
2015
Zhou, Yuping | Tan, Liju | Pang, Qiuting | Li, Feng | Wang, Jiangtao
The influence of nutrients on the growth of Ulva prolifera was studied in the SYS by field experiments. The wet weight of U. prolifera gradiently increased from 11.94% to 25.92% in proportion to contents of DIN supply, which indicated DIN content was essentially decisive for the output of U. prolifera blooms. Continuous nutrient supply could promote the growth of U. prolifera, indicated by the increase of growth rate from 10.46% of the batch culture to 42.17% of the in situ culture. The higher P utilized rate in all treatments showed P was the potential limited factor for the growth of U. prolifera. Moreover, it was calculated about 4.1×105t organic matter was begot by U. prolifera in the whole Yellow Sea based on the statistical relationship between output of U. prolifera and DIN content. This work could be convenient to evaluate biomass and prepare enough tools to manage U. prolifera.
显示更多 [+] 显示较少 [-]Maternal transfer of organohalogenated compounds in sharks and stingrays
2015
Weijs, Liesbeth | Briels, Nathalie | Adams, Douglas H. | Lepoint, Gilles | Dāsa, Kr̥shṇā | Blust, Ronny | Covaci, Adrian
Elasmobranchs can bioaccumulate considerable amounts of persistent organic pollutants (POPs) and utilize several reproductive strategies thereby influencing maternal transfer of contaminants. This study provides preliminary data on the POP transfer from pregnant females to offspring of three species (Atlantic stingrays, bonnethead, blacktip sharks) with different reproduction modes (aplacental, placental viviparity). Polychlorinated biphenyl (PCB) levels were generally higher than any other POPs. Stingrays and blacktip shark embryos contained the lowest POP concentrations while bonnetheads and the blacktip adult female had the highest concentrations. Results suggest that POPs are more readily transferred from the mother to the embryo compared to what is transferred to ova in stingrays. Statistically significant differences in levels of selected POPs were found between embryos from the left and right uterus within the same litter as well as between female and male embryos within the same litter for bonnetheads, but not for the blacktip sharks.
显示更多 [+] 显示较少 [-]Historical trend in heavy metal pollution in core sediments from the Masan Bay, Korea
2015
Cho, Jinhyung | Hyun, Sangmin | Han, J.-H. | Kim, Suhyun | Shin, Dong-Hyeok
The spatiotemporal distribution and their mass accumulation rate (MAR) of heavy metals were investigated to evaluate the time-dependent historical trends of heavy metal concentration. The three short cores used for this study were collected from the catchment area (MS-PC5, 60cm length), the central part (MS-PC4, 40cm length) and the offshore (MS-PC2, 60cm length) of the Masan Bay, Korea. The concentration of heavy metals (Co, Ni, Cu, Zn, Cr and Pb) in catchment area is as much as 1.5–2 times higher than central part of the Bay, and about 2 times higher than offshore area approximately. In particular, MAR of metals (Cu, Zn and Pb) show clear spatiotemporal variation, so that MAR’s of heavy metal may provide more accurate information in evaluating the degree of pollution. Temporally, the heavy metal concentration had been increased since the late 1970s, but it seems to decrease again since the 2004yr in catchment area. This may came from concentrated efforts for the government to reduce industrial waste release.
显示更多 [+] 显示较少 [-]Sterols as biomarkers in the surface microlayer of the estuarine areas
2015
Alsalahi, Murad Ali | Latif, Mohd Talib | Ali, Masni Mohd | Dominick, Doreena | Khan, Md Firoz | Mustaffa, Nur Ili Hamizah | Nadzir, Mohd Shahrul Mohd | Nasher, Essam | Zakaria, Mohamad Pauzi
This study aims to determine the concentration of sterols used as biomarkers in the surface microlayer (SML) in estuarine areas of the Selangor River, Malaysia. Samples were collected during different seasons through the use of a rotation drum. The analysis of sterols was performed using gas chromatography equipped with a flame ionisation detector (GC–FID). The results showed that the concentrations of total sterols in the SML ranged from 107.06 to 505.55ngL−1. The total sterol concentration was found to be higher in the wet season. Cholesterol was found to be the most abundant sterols component in the SML. The diagnostic ratios of sterols show the influence of natural sources and waste on the contribution of sterols in the SML. Further analysis, using principal component analysis (PCA), showed distinct inputs of sterols derived from human activity (40.58%), terrigenous and plant inputs (22.59%) as well as phytoplankton and marine inputs (17.35%).
显示更多 [+] 显示较少 [-]Unravelling the role of zooxanthellae in the uptake and depuration of an essential metal in Exaiptasia pallida; an experiment using a model cnidarian
2015
Hardefeldt, Jannah M. | Reichelt-Brushett, Amanda J.
Coral skeletons record historical trace metal levels in the environment, however, the use of coral skeletal records for biomonitoring studies mostly fail to consider the influence of metal regulation by the living components of coral and subsequent incorporation into the skeleton. This study presents Exaiptasia pallida as a representative of the living components of coral and shows metal partitioning between the tissue and zooxanthellae after chronic exposure to Zn. A strong tendency for preferential accumulation in the zooxanthellae occurred after 32days exposure and Zn concentrations in tissue and zooxanthellae were 123.3±0.7mgkg−1 and 294.9±8.5 respectively. This study shows zooxanthellae density plays an important role in controlling Zn loading in whole anemones and must be considered when investigating metal uptake and loading in zooxanthellate organisms. Further studies that investigate links between aragonite deposition rates and zooxanthellae density and incorporation pathways of metals into skeleton are warranted.
显示更多 [+] 显示较少 [-]Investigation of polycyclic aromatic hydrocarbons (PAHs) and cyclic terpenoid biomarkers in the sediments of fishing harbors in Taiwan
2015
Kao, Nien-Hsin | Su, Ming-Chien | Fan, Jheng-Rong | Yen, Chih-Chun
Three fishing harbors were investigated to study the polycyclic aromatic hydrocarbons in the sediments and trace possible anthropogenic sources by identification of cyclic terpenoid biomarkers. Seventeen terpanes, 10 steranes and 10 bicyclic sesquiterpanes in the marine diesel and the three kinds of lubricants that are mainly used by fishing boats were identified and quantified. Eighteen biomarker diagnostic ratios are suggested and the correlation coefficients among the lubricants and sediment samples have the R2 value greater than 0.73. Analyzed 16 PAHs in the sediment shows non-normal distributions and the Kruskal Wallis Test shows the significant differences (p value smaller than 0.05) with the greatest variability in benzo[g,h,i]perylene which more than 84% of the effective size (E.S.) is accounted. X-ray Photoelectron Spectroscopy (XPS) analysis was applied and the Kruskal Wallis Test shows a significant difference (p value smaller than 0.05) among certain atoms with the effective size greater than 60%.
显示更多 [+] 显示较少 [-]Intrinsic bioremediation potential of a chronically polluted marine coastal area
2015
Catania, Valentina | Santisi, Santina | Signa, Geraldina | Vizzini, Salvatrice | Mazzola, Antonio | Cappello, Simone | Yakimov, Michail M. | Quatrini, Paola
A microbiological survey of the Priolo Bay (eastern coast of Sicily, Ionian Sea), a chronically polluted marine coastal area, was carried out in order to discern its intrinsic bioremediation potential. Microbiological analysis, 16S rDNA-based DGGE fingerprinting and PLFAs analysis were performed on seawater and sediment samples from six stations on two transects. Higher diversity and variability among stations was detected by DGGE in sediment than in water samples although seawater revealed higher diversity of culturable hydrocarbon-degrading bacteria. The most polluted sediment hosted higher total bacterial diversity and higher abundance and diversity of culturable HC degraders. Alkane- and PAH-degrading bacteria were isolated from all stations and assigned to Alcanivorax, Marinobacter, Thalassospira, Alteromonas and Oleibacter (first isolation from the Mediterranean area). High total microbial diversity associated to a large selection of HC degraders is believed to contribute to natural attenuation of the area, provided that new contaminant contributions are avoided.
显示更多 [+] 显示较少 [-]Determinants on ambient PM2.5 infiltration in non-heating season for urban residences in Beijing: Building characteristics, interior surface coverings and human behavior
2015
Huang, Lihui | Hopke, Philip K. | Zhao, Weiping | Li, Mu
Ambient fine particulate matter (PM2.5) pollution is currently a major public health concern in Chinese urban areas. However, assessment of ambient PM2.5 exposure and its health effects is challenging in China because the exposure primarily occurs indoors. There is large inter-home variability of the fraction of ambient PM2.5 that penetrates indoors and remains airborne (Finf), and the factors influencing this variability are unknown. In this study, 24-h real-time indoor and outdoor PM2.5 mass concentrations were concurrently collected for 41 urban residences in the non-heating season. The Finf were estimated with steady-state and dynamic models derived from mass balance considerations. Multivariate statistical analyses were employed to examine the associations between Finf and 78 factors related to building characteristics, motor vehicle traffic, human behavior, meteorology, furnishings, and atmospheric/indoor chemistry. The estimate of Finf over the 24-h monitoring period with the steady-state model was 0.72 ± 0.01; the Finf estimate for single residences, using the dynamic model, were 0.59 ± 0.13 (N = 33). Two predictive models for Finf were constructed with categorical and numerical variables, respectively. The results revealed that building characteristics, traffic, wall and floor coverings, and human behavior had substantial influence on Finf in the non-heating season. The variance contributions of the determinants of traffic, wall and floor coverings, and human behavior were comparable to or even greater than those of the building characteristics.
显示更多 [+] 显示较少 [-]Introduction of the alien Xenostrobus securis (Bivalvia: Mytilidae) into Hong Kong, China: Interactions with and impacts upon native species and the earlier introduced Mytilopsis sallei (Bivalvia: Dreissenidae)
2015
Morton, Brian | Leung, K.F.
This constitutes the first record of the Australian alien mytilid Xenostrobus securis in China. The introduction occurred prior to 2010 probably via shipping arriving at Yantian in Mirs Bay, China, close to Hong Kong. Point sources of infection could be Australia or Korea or Japan where it has similarly been introduced. Analysis of X. securis in Hong Kong shows that it tolerates a wide range of salinities from 5.4‰ to 28.7‰. Water temperatures in Hong Kong match those in its native range.In Hong Kong, X. securis co-occurs with the similarly introduced Mytilopsis sallei and a native bivalve community. The population structure of X. securis suggests a lifespan of >2years with new generations produced by conspecifics. Such a life history strategy is also exhibited by M. sallei. Now established in China, northern Asia, the Mediterranean and, most recently, the Iberian Atlantic, the invasion of other locations by X. securis seems probable.
显示更多 [+] 显示较少 [-]Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia
2015
Maes, Christophe | Blanke, Bruno
Contamination of the marine environment by human-made plastic litter is a growing and global problem. Our study attempts to explain the presence of two plastic bottles beached on the Ouvéa Island, in the southwest Pacific Ocean, with trademarks from the Solomon Islands and Papua New Guinea (PNG). We simulate the oceanic drift tracks and associated transit times with a Lagrangian interpretation of the surface currents of a high-resolution ocean model. Our results show that it takes less than 2–3months for drifting objects to connect these archipelagos (New Caledonia, Solomon Islands and PNG) and highlight the role of the meridional component of the circulation rather than the dominant zonal jets. This study shows that the origin or traceability of trash represent valuable information that can be used to test and, ultimately, improve our understanding of ocean circulation.
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