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A biomonitoring study: Heavy metals in macroalgae from eastern Aegean coastal areas
2011
Akcali, Idil | Kucuksezgin, Filiz
The concentrations of metals were measured in macroalgae species seasonally at eight coastal stations along the eastern Aegean coast. Sediment and seawater samples were also collected to detect their metal contents in order to gain more information on the environmental conditions of the area and possible bioaccumulation patterns. The aim of this study is, to gather more information on the use of selected species as cosmopolitan biomonitors for the eastern Aegean; to provide information on the marine environmental quality by the use of macroalgae and to determine which algae species are suitable as biomonitoring species for the study area. The relative abundance of metals in macroalgae decreases in the order: Fe–Zn–Cu–Cr–Cd–Hg–Pb and seawater: Fe–Zn–Pb–Cu–Cr–Cd–Hg. In sediment the distribution order from higher to lower was Fe–Cr–Zn–Pb–Cu–Hg–Cd. The brown algae Cystoseira sp., the green algae Ulva sp. and Enteromorpha sp. possess high potential as cosmopolitan biomonitors for trace metals in the Aegean Sea.
Show more [+] Less [-]Matrix-bound phosphine in sediments from Lake Illawarra, New South Wales, Australia
2011
Song, Xiuxian | Morrison, R.J. | Feng, Zhihua | Liu, Dongyan | Harrison, J.J. | Yu, Zhiming
Matrix-bound phosphine (MBP) has been measured in sediment from two cores in Lake Illawarra on the south east coast of Australia. The sediments were also dated in the upper layers. MBP concentrations found range from 142 to 1813ngkg⁻¹, dw (dry weight of sediment) with some values being amongst the highest ever measured. Values of MBP in deeper sediments were higher than for near surface samples, but the patterns with depth were not consistent. Strong correlations were noted between MBP and organic phosphorus (OP, r>0.8) and with total phosphorus (TP, r>0.7), but only moderate correlations were found with organic carbon (OC, r>0.5). No correlations were found between MBP concentrations and the age of the sediments. It was confirmed that high MBP concentrations are indicative of a phosphorus rich environment. The results tend to support the premise that MBP is generated by microbial attack on OP under anaerobic conditions.
Show more [+] Less [-]Estuarine ecological risk based on hepatic histopathological indices from laboratory and in situ tested fish
2011
Costa, Pedro M. | Caeiro, Sandra | Lobo, Jorge | Martins, Marta | Ferreira, Ana M. | Caetano, Miguel | Vale, Carlos | DelValls, T Ángel | Costa, Maria H.
Juvenile Senegalese soles were exposed through 28-day laboratory and field (in situ) bioassays to sediments from three sites of the Sado estuary (W Portugal): a reference and two contaminated by metallic and organic contaminants. Fish were surveyed for ten hepatic histopathological alterations divided by four distinct reaction patterns and integrated through the estimation of individual histopathological condition indices. Fish exposed to contaminated sediments sustained more damage, with especial respect to regressive changes like necrosis. However, differences were observed between laboratory- and field-exposed animals, with the latest, for instance, exhibiting more pronounced fatty degeneration and hepatocellular eosinophilic alteration. Also, some lesions in fish exposed to the reference sediment indicate that in both assays unaccounted variables produced experimental background noise, such as hyaline degeneration in laboratory-exposed fish. Still, the field assays yielded results that were found to better reflect the overall levels of contaminants and physico-chemical characteristics of the tested sediments.
Show more [+] Less [-]Benthic macroinvertebrates as indicators of environmental deterioration in a large microtidal estuary
2011
Wildsmith, M.D. | Rose, T.H. | Potter, I.C. | Warwick, R.M. | Clarke, K.R.
This study tested the hypothesis that, during recent years, the benthic macroinvertebrate fauna of the large basin of the Swan-Canning Estuary has changed in ways consistent with deteriorating environmental conditions in that estuary. Between 1986/7 and 2003/4, the compositions of that fauna altered markedly at the species and even family levels. Thus, the densities and number of species of molluscs, and especially of crustaceans, which are particularly susceptible to environmental stress, declined, while those of the more tolerant polychaetes increased. However, taxonomic distinctness declined consistently only at one of the four widely-spaced sampling sites and the dispersion of samples did not differ markedly between periods, indicating that the benthic fauna has not undergone such extreme changes as in the nearby Peel-Harvey Estuary. It is thus proposed that benthic macroinvertebrates can act as important indicators of the severity of environmental degradation in microtidal estuaries in regions where such perturbations are increasing.
Show more [+] Less [-]Relationship of photosynthetic carbon fixation with environmental changes in the Jiulong River estuary of the South China Sea, with special reference to the effects of solar UV radiation
2011
Li, Gang | Gao, Kunshan | Yuan, Dongxing | Zheng, Ying | Yang, Guiyuan
Phytoplankton cells in estuary waters usually experience drastic changes in chemical and physical environments due to mixing of fresh and seawaters. In order to see their photosynthetic performance in such dynamic waters, we measured the photosynthetic carbon fixation by natural phytoplankton assemblages in the Jiulong River estuary of the South China Sea during April 24–26 and July 24–26 of 2008, and investigated its relationship with environmental changes in the presence or the absence of UV radiation. Phytoplankton biomass (Chl a) decreased sharply from the river-mouth to seawards (17.3–2.1μgL⁻¹), with the dominant species changed from chlorophytes to diatoms. The photosynthetic rate based on Chl a at noon time under PAR-alone increased from 1.9μgC (μg Chl a)⁻¹L⁻¹ in low salinity zone (SSS<10) to 12.4μgC (μg Chl a)⁻¹L⁻¹ in turbidity front (SSS within 10–20), and then decreased to 2.1μgC (μg Chl a)⁻¹L⁻¹ in mixohaline zone (SSS>20); accordingly, the carbon fixation per volume of seawater increased from 12.8 to 149μgCL⁻¹h⁻¹, and decreased to 14.3μgCL⁻¹h⁻¹. Solar UVR caused the inhibition of carbon fixation in surface water of all the investigated zones, by 39% in turbidity area and 7–10% in freshwater or mixohaline zones. In the turbidity zone, higher availability of CO₂ could have enhanced the photosynthetic performance; while osmotic stress might be responsible for the higher sensitivity of phytoplankton assemblages to solar UV radiation.
Show more [+] Less [-]Biomarker responses in pelagic and benthic fish over 1 year following the Hebei Spirit oil spill (Taean, Korea)
2011
Jung, Jee-Hyun | Kim, Moonkoo | Yim, Un Hyuk | Ha, Sung Yong | An, Joon Geon | Won, Jong Ho | Han, Gi Myung | Kim, Nam Sook | Addison, R. F. | Shim, Won Joon
After the Hebei Spirit oil spill incident (7th December, 2007) in the west coast of Korea, contamination of biliary PAH metabolite and hepatic biomarkers in a pelagic and a benthic fish was monitored for 1 year. Concentrations of 16 PAHs and alkylated PAHs in fish muscle were highest (22.0ng/g d.w. for 16 PAHs and 284ng/g d.w. for alkylated PAHs) at 5 days after the spill and then decreased rapidly to background levels at 11months after the spill. Fish from the oiled site had elevated biliary PAH metabolite concentrations immediately after the spill; these declined steadily in both species, but were still above reference site concentrations 2 months after the spill. Oiled-site fish showed hepatic CYP 1A induction whose trend closely followed those of biliary PAH metabolite concentrations, implying continuous exposure to PAHs. Brain acetylcholinesterase activity was not related to oil exposure.
Show more [+] Less [-]The use of Lagrangian trajectories for the identification of the environmentally safe fairways
2011
Soomere, Tarmo | Andrejev, Oleg | Myrberg, Kai | Sokolov, Alexander
We propose and test a method for the optimisation of marine fairways to minimise the risk to high-value areas, based on statistical analysis of Lagrangian trajectories of current-driven pollution transport. The offshore areas are quantified according to the probability of pollution released in these areas to reach vulnerable regions. The method contains an eddy-resolving circulation model, a scheme for tracking of Lagrangian trajectories, a technique for the calculation of quantities characterising the potential of different sea areas to supply adverse impacts, and routines to construct the optimum fairway. The gain is expressed in terms of the probability of pollution transport to the nearshore and the associated time (particle age). The use of the optimum fairway would decrease the probability of coastal pollution by 40% or increase the average time of reaching the pollution to the coast from 5.3 to about 9days in the Gulf of Finland, the Baltic Sea.
Show more [+] Less [-]Why are hatching and emergence success low? Mercury and selenium concentrations in nesting leatherback sea turtles (Dermochelys coriacea) and their young in Florida
2011
Perrault, Justin | Wyneken, Jeanette | Thompson, Larry J. | Johnson, Chris | Miller, Debra L.
Leatherback sea turtles (Dermochelys coriacea) have low hatching and emergence success compared to other sea turtle species. Postmortem examinations of hatchlings showed degeneration of heart and skeletal muscle that was similar to that found in other neonates with selenium deficient mothers. Selenium deficiency can result from elevated concentrations of bodily mercury. Ingested mercury is detoxified by the liver through mercury–selenium compound formation. In animals persistently exposed to mercury, the liver’s ability to detoxify this element may decrease, especially if dietary selenium is insufficient. We measured mercury and selenium concentrations in nesting female leatherbacks and their hatchlings from Florida and compared the levels to hatching and emergence success. Both liver selenium and the liver selenium-to-mercury ratio positively correlated with leatherback hatching and emergence success. This study provides the first evidence for the roles of mercury and selenium in explaining low reproductive success in a globally imperiled species, the leatherback sea turtle.
Show more [+] Less [-]Organic micropollutants in marine plastics debris from the open ocean and remote and urban beaches
2011
Hirai, Hisashi | Takada, Hideshige | Ogata, Yuko | Yamashita, Rei | Mizukawa, Kaoruko | Saha, Mahua | Kwan, Charita | Moore, Charles | Gray, Holly | Laursen, Duane | Zettler, Erik R. | Farrington, John W. | Reddy, Christopher M. | Peacock, Emily E. | Ward, Marc W.
To understand the spatial variation in concentrations and compositions of organic micropollutants in marine plastic debris and their sources, we analyzed plastic fragments (∼10mm) from the open ocean and from remote and urban beaches. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), dichloro-diphenyl-trichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), alkylphenols and bisphenol A were detected in the fragments at concentrations from 1 to 10,000ng/g. Concentrations showed large piece-to-piece variability. Hydrophobic organic compounds such as PCBs and PAHs were sorbed from seawater to the plastic fragments. PCBs are most probably derived from legacy pollution. PAHs showed a petrogenic signature, suggesting the sorption of PAHs from oil slicks. Nonylphenol, bisphenol A, and PBDEs came mainly from additives and were detected at high concentrations in some fragments both from remote and urban beaches and the open ocean.
Show more [+] Less [-]Total mercury in sediments and in Brazilian Ariidae catfish from two estuaries under different anthropogenic influence
2011
Azevedo, Juliana S. | Braga, Elisabete S. | Favaro, Deborah T. | Perretti, Adriana R. | Rezende, Carlos Eduardo | Souza, Cristina Maria M.
Santos-São Vicente estuary, located in São Paulo State, Brazil, has a history of contamination by inorganic chemicals such as mercury (Hg). In the 1980s the Cubatão was considered one of the most polluted sites in the world as a consequence of the intense industrial activities located in the city close to the estuary. To provide data and evaluate the local biota, total mercury (THg) contents were determined in sediments and in fish, Cathorops spixii, from different areas of the Santos-São Vicente estuary. For comparison, samples were also collected in a non-polluted system with similar hydrochemistry characteristics, the Cananeia estuary. The water characteristics and THg levels in sediment and fish samples confirmed a high human influence in the Santos-São Vicente estuary. The lowest THg values, observed in Cananeia, were evidence of low anthropogenic influence. High values observed in Santos-São Vicente show the necessity for a monitoring program.
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