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Water characterization in three industrialized harbours (Vigo, Bilbao and Pasajes) in North Coast of Spain Полный текст
2012
Durán, Iria | Nieto, Oscar
Total dissolved Cu, Zn, Pb and Cd concentrations, speciation, fluorescence of organic matter and toxicity for sea urchin development have been studied during three years in water samples of three of the most industrialized harbours in North Coast of Spain: Vigo, Bilbao and Pasajes. Total metal concentrations were below 0.4nM for Cd and generally below 2nM for Pb. Zn and Cu levels were higher (2.8–9nM Cu and 15–234nM Zn) and denoted an anthropogenic enrichment. Ligand concentrations were usually between 50 and 200nM for Cu and between 6 and 80 for Pb and Zn. Organic matter and speciation analysis yielded complementary information to characterize the samples, but no correlation was present between the parameters calculated by both methods. Samples were tested for toxicity with sea urchin embryo bioassay and three samples were toxic but the toxicity could not be explained with the metal levels here measured.
Показать больше [+] Меньше [-]Impacts of human activities on coral reef ecosystems of southern Taiwan: A long-term study Полный текст
2012
Liu, Pi-Jen | Meng, Pei-Jie | Liu, Li-Lian | Wang, Jih-Terng | Leu, Ming-Yih
In July 2001, the National Museum of Marine Biology and Aquarium, co-sponsored by the Kenting National Park Headquarters and Taiwan’s National Science Council, launched a Long-Term Ecological Research (LTER) program to monitor anthropogenic impacts on the ecosystems of southern Taiwan, specifically the coral reefs of Kenting National Park (KNP), which are facing an increasing amount of anthropogenic pressure. We found that the seawater of the reef flats along Nanwan Bay, Taiwan’s southernmost embayment, was polluted by sewage discharge at certain monitoring stations. Furthermore, the consequently higher nutrient and suspended sediment levels had led to algal blooms and sediment smothering of shallow water corals at some sampling sites. Finally, our results show that, in addition to this influx of anthropogenically-derived sewage, increasing tourist numbers are correlated with decreasing shallow water coral cover, highlighting the urgency of a more proactive management plan for KNP’s coral reefs.
Показать больше [+] Меньше [-]Ascidian introductions through the Suez Canal: The case study of an Indo-Pacific species Полный текст
2012
Rius, Marc | Shenkar, Noa
Although marine biological invasions via the Suez Canal have been extensively documented, little is known about the introduction of non-indigenous ascidians (Chordata, Ascidiacea), a group containing particularly aggressive invasive species. Here, we used a multidisciplinary approach to study the introduction of the ascidian Herdmania momus into the Mediterranean Sea. We reviewed its taxonomy and global distribution, and analyzed how genetic variation is partitioned between sides of the Suez Canal. The taxonomic revision showed that H. momus currently has a wide Indo-Pacific distribution. Genetic data indicated two well-differentiated colonization histories across the eastern Mediterranean. Our findings suggest that the range expansion of H. momus has been greatly facilitated by the combined effect of human-mediated transport and the species’ ability to adapt to different environments. The integrative approach presented here is critical to attain a holistic understanding of marine biological invasions, especially when studying groups with a poorly resolved taxonomy.
Показать больше [+] Меньше [-]Spread of Alsidium corallinum C. Ag. in a Tyrrhenian eutrophic lagoon dominated by opportunistic macroalgae Полный текст
2012
Lenzi, Mauro | Gennaro, Paola | Renzi, Monia | Persia, Emma | Porrello, Salvatore
In 2007, the Rhodophyceae Alsidium corallinum C. Ag., a marine taxon, bloomed in the eutrophic lagoon of Orbetello (Tuscany, Italy) for the first time, becoming the dominant species in spring and summer. In November, its biomass collapsed. The hypothesis examined in this study is that the bloom expressed a relatively low eutrophic level of the ecosystem after intense disposal of accumulated sedimentary organic matter (OM) by dystrophic processes in the two years preceding the bloom. To verify the hypothesis, we compared water physical–chemical variables, sediment redox (Eh) and OM, and standing crops of macroalgae and seagrass from the database of routine monitoring between 2005 and 2008. We also used dissolved nutrient data obtained in 2007 and 2008, as well as data on chlorophyll and total suspended matter in the water column during the microalgal bloom of 2007, and C, N and P content in thalli of the Chlorophycea Chaetomorpha linum and the Rhodophyceae Gracilariopsis longissima and A. corallinum obtained in 2007. In 2007, unusually low values of dissolved inorganic nitrogen (DIN) were recorded. Combined with stable values of soluble reactive phosphorus (SRPs), low DIN led to a reduction of about one order of magnitude in the DIN:SRP atomic ratio with respect to the past and to 2008. G. longissima accumulated C, N and P more than the other species and A. corallinum proved to be less demanding. Sediment OM was lower in the autumn of years characterized by dystrophy, confirming that summer dystrophic events coincided with maximum energy dissipation in this ecosystem. However, as soon as OM and DIN values increased (2008), the vegetation shifted towards blooms of G. longissima and C. linum, while A. corallinum almost disappeared. The results sustain the hypothesis that the bloom of A. corallinum was due to a decline in DIN that limited G. longissima, and to intense turbidity of the water caused by microphytes that developed after the dystrophic event of summer 2006. The latter probably limited the development of C. linum, which could only develop at the edges of the lagoon.
Показать больше [+] Меньше [-]Island shadow effects and the wave climate of the Western Tuamotu Archipelago (French Polynesia) inferred from altimetry and numerical model data Полный текст
2012
Andréfouët, Serge | Ardhuin, Fabrice | Queffeulou, Pierre | Le Gendre, Romain
To implement a numerical model of atoll lagoon circulation, we characterized first the significant wave height (Hs) regime of the Western Tuamotu Archipelago and the local attenuation due to the protection offered by large atolls in the south Tuamotu. Altimetry satellite data and a WAVEWATCH III two-way nested wave model at 5km resolution from 2000 to 2010 were used. Correlation between altimetry and model was high (0.88) over the period. According to the wave model, the archipelago inner seas experienced attenuated Hs year-long with a yearly average Hs around 1.3m vs a minimum of 1.6m elsewhere. The island shadow effect is especially significant in the austral winter. In contrast with southern atolls, Western Tuamotu experienced only few days per year of Hs larger than 2.5m generated by very high Hs southern swell, transient western local storms, strong easterly winds, and during the passage of distant hurricanes.
Показать больше [+] Меньше [-]Long-term decreases in persistent organic pollutants in South African coastal waters detected from beached polyethylene pellets Полный текст
2012
Ryan, Peter G. | Bouwman, Hindrik | Moloney, Coleen L. | Yuyama, Masaki | Takada, Hideshige
Polyethylene pellets provide a convenient means to monitor Persistent Organic Pollutants (POPs) in marine systems. Pellets collected between 1984 and 2008 at three South African beaches were analysed for PCB, HCH and DDT. Concentrations of all three POPs decreased over the last two decades, although this signal was less clear for PCBs, and further monitoring is needed to assess trends in this family of compounds. DDT concentrations at two sites were higher than previous records for southern Africa, but there is no evidence of a link to the ongoing use of DDT for malaria control. HCHs concentrations were lower than in pellets from the east coast of southern Africa, suggesting that this pesticide was mainly used in the eastern part of the region. Our study demonstrates the potential for International Pellet Watch to track temporal as well as geographical patterns in the abundance of POPs in marine environments.
Показать больше [+] Меньше [-]Onshore ballast water treatment: A viable option for major ports Полный текст
2012
Pereira, Newton Narciso | Brinati, Hernani Luiz
Ballast water treatment consists of the elimination of exotic species. Currently, the development of alternative methods for this process is directed toward treatment onboard ships. However, we present onshore treatment as a viable alternative for ballast water treatment. We investigated onshore treatment in two iron ore ports with movement capacities of 25 and 90million tons annually (Mta) that receive 7.5 and 25million cubic meters annually (Mm³) of ballast water, respectively. Discrete event simulation was used as the method of analysis, considering the processes of arrival, berthing, ship loading and capture and treatment of ballast water. We analyzed data from 71 ships operating in these ports to validate our simulation model. We were able to demonstrate that onshore treatment does not impact the cargo capacity, occupation rate or average queuing time of ships at these ports. We concluded that implementation of onshore ballast water treatment may be practicable in ports that receive high volumes of ballast water.
Показать больше [+] Меньше [-]Overview of the 20th century impact of trace metal contamination in the estuaries of Todos os Santos Bay: Past, present and future scenarios Полный текст
2012
Hatje, Vanessa | Barros, Francisco
This paper discusses the distribution patterns of trace metals in sediments and suspended particulate matter (SPM) in the three main estuaries of the Todos os Santos Bay (BTS), Brazil, during dry and rainy seasons. Data available up to 2012 was also reviewed to assess the status of contamination. For most elements, metal concentrations in sediments decreased from the tidal limits to the lower estuary. Metals in SPM presented more complex distributions along the salinity gradient. Metal variability between rainy and dry conditions was only significant for SPM data. Of the BTS estuaries, the levels of Cd, Zn, Pb and Cu are highest in the Subaé estuary, and they seem to be promoting harmful biological effects in macrofauna, and also may pose potential human health risks. Despite the evidence of important localized contamination, much of the data compiled indicates that the bay and its estuaries are still relatively preserved.
Показать больше [+] Меньше [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Полный текст
2012
Harmelin-Vivien, M. L. (Mireille L.) | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Véronique | Mellon-Duval, Capucine | Tronczyński, Jacek | Cossa, Daniel
Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Полный текст
2012
Harmelin-Vivien, M. L. (Mireille L.) | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Véronique | Mellon-Duval, Capucine | Tronczyński, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and ¹³⁷Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism’s trophic level (δ¹⁵N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and ¹³⁷Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.
Показать больше [+] Меньше [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Полный текст
2012
Harmelin-vivien, Mireille | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Veronique | Mellon, Capucine | Tronczynski, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and Cs-137) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (delta N-15). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and Cs-137, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants. (C) 2012 Elsevier Ltd. All rights reserved.
Показать больше [+] Меньше [-]Perylene dominates the organic contaminant profile in the Berau delta, East Kalimantan, Indonesia Полный текст
2012
Booij, Kees | Arifin, Zainal | Purbonegoro, Triyoni
The geographical distributions of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), hexachlorobenzene, and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene (4,4′-DDE) were studied in the Berau delta (East Kalimantan, Indonesia), using sediment sampling and passive water sampling with semipermeable membrane devices. High concentrations of perylene were observed in sediments (54–580ngg⁻¹ dry weight), and water (1–680pgL⁻¹). Perylene accounted for about 60% of the total concentrations of PAHs in the sediment. The relative abundance of the other PAHs was indicative of petrogenic sources. Concentrations of PCBs, hexachlorobenzene, and 4,4′-DDE in sediments were below or close to the detection limit (∼0.02ngg⁻¹). The analysis of a sediment core revealed no appreciable changes in the concentration of target compounds over the past three decades. We show that sediment sampling and passive water sampling are complementary techniques, and propose to bring the results of both methods to the same concentration scale, using locally derived sediment–water partition coefficients.
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