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Occurrence and distribution of antifouling biocide Irgarol-1051 in coastal waters of Peninsular Malaysia
2013
Ali, Hassan Rashid | Arifin, Marinah Mohd | Sheikh, Mohammed Ali | Mohamed Shazili, Noor Azhar | Zainudin Bachok,
Emerging booster biocides contamination raises particular attention in the marine ecosystem health. This study provides the baseline data on the occurrence of Irgarol-1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamiono-s-triazine) in the selected coastal water around Malaysia. The maximum detected concentration of Irgarol was 2021ng/L at Klang West, commercial and cargo port. Coral reef Islands (Redang and Bidong) were relatively less contaminated compared to other coastal areas. The temporal variation revealed that only 1% of 28 stations sampled on November, 2011 was above the environmental risk limit of 24ng/L as suggested by Dutch Authorities, while in January and April, 2012; 46% and 92% of the stations were above the limit respectively. The present findings demonstrate the wide detection of novel antifouling materials Irgarol-1051 which advocates the need for proper monitoring and conservation strategies for the coastal resources.
Afficher plus [+] Moins [-]Looking at the aquatic contamination through fish eyes – A faithful picture based on metals burden
2013
Pereira, Patrícia | Raimundo, Joana | Canário, João | Almeida, Armando | Pacheco, Mario
This study describes for the first time metal accumulation in the eyes of native golden grey mullet (Liza aurata) coupled with water/sediment quality assessment. Sampling was performed in the Tagus estuary (Portugal) where a confined area (Barreiro) is severely contaminated by metal/loids. Levels of As, Cu, Pb, Hg and Cd in sediments from Barreiro were one order of magnitude higher than those from the reference site. Data on water column pointed also to a higher availability of Cu, Pb, Cd and Hg (including MeHg) at Barreiro. Accordingly, fish eyes accumulated higher levels of metal/loids at Barreiro than at the reference site. These findings support the use of fish eyes as a target organ in environmental health assessment since they reflect sediment and water contamination. It points also to the importance of evaluate eye changes at structural/functional levels in order to examine in what extent accumulated metals could compromise this perceptive system.
Afficher plus [+] Moins [-]Heavy metal pollution in coastal areas of South China: A review
2013
Wang, Shuai-Long | Xu, Xiang-Rong | Sun, Yu-Xin | Liu, Jin-Ling | Li, Hua-Bin
Coastal areas of South China face great challenges due to heavy metal contamination caused by rapid urbanization and industrialization. In this paper, more than 90 articles on levels, distributions, and sources of heavy metals in sediments and organisms were collected to review the status of heavy metal pollution along coastal regions of South China. The results show that heavy metal levels were closely associated with local economic development. Hong Kong and the Pearl River Estuary were severely contaminated by heavy metals. However, concentrations of heavy metals in sediments from Hong Kong have continually decreased since the early 1990s. High levels of heavy metals were found in biota from Lingdingyang in Guangdong province. Mollusks had higher concentrations of heavy metals than other species. Human health risk assessments suggested that levels of heavy metals in some seafood from coastal areas of South China exceeded the safety limit.
Afficher plus [+] Moins [-]Source apportionment of sedimentary hydrocarbons in the Segara Anakan Nature Reserve, Indonesia
2013
Syakti, Agung Dhamar | Hidayati, Nuning Vita | Hilmi, Endang | Piram, Anne | Doumenq, Pierre
The study aimed to determine the spatial distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Segara Anakan nature reserve and their potential origins using gas chromatography–mass spectrometry. Total alkane concentrations ranged from 3755 to 129,027μgkg−1, and the concentrations of 16 PAHs ranged from 375 to 29,517μgkg−1. The ratios of specific n-alkanes (e.g., CPI24–34, WaxCn, and Paq), including a new proposed index, terrestrial–marine discriminant (TMD), as well as the ratios of selected PAHs (e.g., Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276), showed that the sources of hydrocarbons in the sediments were generally biogenic, including both terrigenous and marine, with an anthropogenic pyrolytic contribution (petrogenic and biogenic combustion). For the environmental risk assessment, a sediment quality guideline (SQGs) comparison indicated that the station risk levels ranged from low to medium-low, except for R6, which has a greater impact on the ecological risk for marine organisms.
Afficher plus [+] Moins [-]Biogeochemical classification of South Florida’s estuarine and coastal waters
2013
Briceño, Henry O. | Boyer, Joseph N. | Castro, Joffre | Harlem, Peter
South Florida’s watersheds have endured a century of urban and agricultural development and disruption of their hydrology. Spatial characterization of South Florida’s estuarine and coastal waters is important to Everglades’ restoration programs. We applied Factor Analysis and Hierarchical Clustering of water quality data in tandem to characterize and spatially subdivide South Florida’s coastal and estuarine waters. Segmentation rendered forty-four biogeochemically distinct water bodies whose spatial distribution is closely linked to geomorphology, circulation, benthic community pattern, and to water management. This segmentation has been adopted with minor changes by federal and state environmental agencies to derive numeric nutrient criteria.
Afficher plus [+] Moins [-]Eco-hydro-acoustic modeling and its use as an EIA tool
2013
Rossington, Kate | Benson, Tom | Lepper, Paul | Jones, Diane
The effects of anthropogenic underwater noise on marine life is of growing concern and assessment of impacts on marine life is often carried out using predictive underwater noise models to map zones of influence for marine species. However, these models do not predict how a species may react to that noise. In this paper, the results from a modified predictive underwater noise model and a hydrodynamic model are used in an individual based model (IBM) to predict the impacts on cod (Gadhus moruha) from noise generated during a pile driving event at an offshore wind farm in Liverpool Bay, UK. The model included cod which were sensitive to noise and those which were insensitive (‘deaf’). Fish movement was from the outer bay into the Dee Estuary, a known feeding ground. The IBM indicated that the cod which could hear took up to 7days longer to reach their destination than the cod which were deaf. This technique could be used during the consenting process for offshore projects to better understand the potential impact on marine species.
Afficher plus [+] Moins [-]Developing human capital for successful implementation of international marine scientific research projects
2013
Morrison, R.J. | Zhang, J. | Urban, E.R. | Hall, J. | Ittekkot, V. | Avril, B. | Hu, L. | Hong, G.H. | Kidwai, S. | Lange, C.B. | Lobanov, V. | Machiwa, J. | San Diego-McGlone, M.L. | Oguz, T. | Plumley, F.G. | Yeemin, T. | Zhu, W. | Zuo, F.
The oceans play a crucial role in the global environment and the sustainability of human populations, because of their involvement in climate regulation and provision of living and non-living resources to humans. Maintenance of healthy oceans in an era of increasing human pressure requires a high-level understanding of the processes occurring in the marine environment and the impacts of anthropogenic activities. Effective protection and sustainable resource management must be based, in part, on knowledge derived from successful research. Current marine research activities are being limited by a need for high-quality researchers capable of addressing critical issues in broad multidisciplinary research activities. This is particularly true for developing countries which will require the building of capacity for marine scientific research. This paper reviews the current activities aimed at increasing marine research capacity in developing and emerging countries and analyses the challenges faced, including: appropriate alignment of the research goals and societal and policy-relevant needs; training in multidisciplinary research; increasing capacity for overall synthesis of scientific data; building the capacity of technical staff; keeping highly qualified personnel in marine scientific research roles; cross-cultural issues in training; minimising duplication in training activities; improving linkages among human capital, project resources and infrastructure. Potential solutions to these challenges are provided, along with some priorities for action aimed at improving the overall research effort.
Afficher plus [+] Moins [-]Post-release survival of surf scoters following an oil spill: An experimental approach to evaluating rehabilitation success
2013
De La Cruz, Susan E.W. | Takekawa, John Y. | Spragens, Kyle A. | Yee, Julie | Golightly, Richard T. | Massey, Gregory W. | Henkel, Laird A. | Scott Larsen, R. | Ziccardi, Michael
Birds are often the most numerous vertebrates damaged and rehabilitated in marine oil spills; however, the efficacy of avian rehabilitation is frequently debated and rarely examined experimentally. We compared survival of three radio-marked treatment groups, oiled, rehabilitated (ORHB), un-oiled, rehabilitated (RHB), and un-oiled, non-rehabilitated (CON), in an experimental approach to examine post-release survival of surf scoters (Melanitta perspicillata) following the 2007 M/V Cosco Busan spill in San Francisco Bay. Live encounter-dead recovery modeling indicated that survival differed among treatment groups and over time since release. The survival estimate (±SE) for ORHB was 0.143±0.107 compared to CON (0.498±0.168) and RHB groups (0.772±0.229), suggesting scoters tolerated the rehabilitation process itself well, but oiling resulted in markedly lower survival. Future efforts to understand the physiological effects of oil type and severity on scoters are needed to improve post-release survival of this species.
Afficher plus [+] Moins [-]Trace metal contamination of the aquatic plant Hydrilla verticillata and associated sediment in a coastal Alabama creek (Gulf of Mexico – USA)
2013
Lafabrie, C. | Major, K.M. | Major, C.S. | Cebrián, J.
The objectives of this study were to (i) assess trace metal concentrations in Hydrilla verticillata and sediment from an estuarine creek in Alabama (USA), where high metal levels in biota were previously reported, and (ii) investigate the relationship between metal concentrations in H. verticillata and the sediment compartment. Our results indicate that sediment and H. verticillata exhibit moderate metal concentrations in the study area. We found that levels in plant tissues can be up to five times higher than in the sediment (e.g., Cd), suggesting that H. verticillata can take up and store several trace metals (Cd, Hg, Ni, and Zn) from this compartment. Together with studies focused on the uptake and accumulation of trace metals from the surrounding water, laboratory- and field-based studies are needed to better evaluate this plant’s ability to acquire metals from the sediment that constitutes a contaminant sink in human-impacted coastal regions.
Afficher plus [+] Moins [-]As main meal for sperm whales: Plastics debris
2013
de Stephanis, Renaud | Giménez, Joan | Carpinelli, Eva | Gutierrez-Exposito, Carlos | Cañadas, Ana
Marine debris has been found in marine animals since the early 20th century, but little is known about the impacts of the ingestion of debris in large marine mammals. In this study we describe a case of mortality of a sperm whale related to the ingestion of large amounts of marine debris in the Mediterranean Sea (4th published case worldwide to our knowledge), and discuss it within the context of the spatial distribution of the species and the presence of anthropogenic activities in the area that could be the source of the plastic debris found inside the sperm whale. The spatial distribution modelled for the species in the region shows that these animals can be seen in two distinct areas: near the waters of Almería, Granada and Murcia and in waters near the Strait of Gibraltar. The results shows how these animals feed in waters near an area completely flooded by the greenhouse industry, making them vulnerable to its waste products if adequate treatment of this industry’s debris is not in place. Most types of these plastic materials have been found in the individual examined and cause of death was presumed to be gastric rupture following impaction with debris, which added to a previous problem of starvation. The problem of plastics arising from greenhouse agriculture should have a relevant section in the conservation plans and should be a recommendation from ACCOBAMS due to these plastics’ and sperm whales’ high mobility in the Mediterranean Sea.
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