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Pollutant bioaccumulation in the California spiny lobster (Panulirus interruptus) in San Diego Bay, California, and potential human health implications Texte intégral
2018
Loflen, Chad L. | Buck, Travis | Bonnema, Autumn | Heim, Wesley A.
While the California spiny lobster (Panulirus interruptus) is an important commercial and recreational fishery species in California, there is a lack of data on bioaccumulation for the species. This study examined pollutant tissue concentrations in lobsters from San Diego Bay, California. Observed lobster pollutant tissue concentrations in tail muscle were compared to State of California pollutant advisory levels. Concentrations were then used to conduct risk assessment using catch data from the California Department of Fish and Wildlife.Study results found little bioaccumulation of organic pollutants in tail tissue, likely due to low observed lipids. Mercury was present, predominantly in methyl form, at concentrations above advisory levels. Recreational catch data for San Diego Bay showed increased non-cancer risk for fishers at the 90th percentile or greater of reported annual catch. Further studies should focus on non-tail tissues, as exploratory whole lobster samples (n = 2) showed elevated organic pollutants and metals.
Afficher plus [+] Moins [-]Microplastics in wastewater: State of the knowledge on sources, fate and solutions Texte intégral
2018
Prata, Joana Correia
Microplastics are ubiquitous contaminants that could harm ecosystems. Wastewater contains microplastics and may lead to further contamination of the environment. This focus article presents a summary of current knowledge on microplastics in wastewater and possible solutions, suggesting current research needs.
Afficher plus [+] Moins [-]Abundance and distribution of benthic foraminifera as indicators of the quality of the sedimentary environment in a subtropical lagoon, Gulf of California Texte intégral
2018
Gómez-León, Adriana | Rodríguez-Figueroa, Griselda M. | Shumilin, Evgueni | Carreño, Ana Luisa | Sánchez, Alberto
Abundance and spatial distribution of benthic foraminifera were used to evaluate the impacts of anthropogenic activities on sediment quality in a coastal lagoon in the Gulf of California. In 1985 and 2013, 27 samples of superficial sediments were collected. The foraminifera genera Ammonia, Cribroelphidium, Quinqueloculina and Peneroplis were dominant in both years. The abundance of Ammonia increased from 41% to 60%, while Peneroplis abundance decreased from a maximum of 50% in 1985 to 7% in 2013. The greater abundance of Ammonia and the greater spatial coverage of Ammonia and Cribroelphidium suggest a marked environmental deterioration in the quality of the sedimentary environment, which contrasts with studies of trace elements in the sediment of this lagoon. The Foram Stress Index indicates that sediment quality has deteriorated over time, likely due to the effects of anthropogenic activities around the lagoon.
Afficher plus [+] Moins [-]Microplastic in beach sediments of the Isle of Rügen (Baltic Sea) - Implementing a novel glass elutriation column Texte intégral
2018
Hengstmann, Elena | Tamminga, Matthias | vom Bruch, Constantin | Fischer, Elke Kerstin
To extent the understanding on microplastics in the marine environment we performed a case study at four beaches on the Isle of Rügen considering abundance and spatial distribution of microplastics in beach sediments. For the analysis, density separation via a glass elutriation column was implemented. In advance, efficiencies were tested for two polymers, being not buoyant in water. Recovery rates of 80% for PET and 72% for PVC particles in sandy samples were achieved.A median abundance of 88.10 (Q1=55.01/Q3=114.72) microplastic particles per kg dry sediment or 2862.56 (Q1=1787.34/Q3=3727.28) particles per m2 was found at the beaches on Rügen. Fibers were more abundant than fragments at all beaches. In this study, no statistically significant differences but only tendencies were determined between the beaches with different exposition and anthropogenic activity as well as for distribution patterns which showed that microplastic fragments accumulate in topographic depressions, similar to macrolitter items.
Afficher plus [+] Moins [-]Ammunition detection using high frequency multibeam snippet backscatter information Texte intégral
2018
Kunde, Tina | Held, Philipp | Sternberg, Harald | Schneider von Deimling, Jens
The present study reports the evaluation of snippet backscatter information gathered with a high-frequency multibeam echosounder system (200–400 kHz) due to their usability to detect ammunition of different sizes in shallow coastal waters. Besides the feasibility of the snippet backscatter data, it was focused on the attainable horizontal accuracy in comparison to side-scan sonar and autonomous underwater vehicle (AUV) surveys. The data was collected in shallow coastal waters of up to 18 m water depth (Baltic Sea) close to an ammunition dumping site characterized by an almost flat seafloor covered with sand and silt sediments. The analysis of the multibeam compared to sidescan data indicates the snippet backscatter to be a promising prospective method for ammunition detection and being able to improve horizontal position accuracy of up to 0.08 m.
Afficher plus [+] Moins [-]Marine protected areas and spatial fetishism: A viewpoint on destructive fishing in coastal Tanzania Texte intégral
2018
Raycraft, Justin
This paper focuses on destructive fishing practices in coastal Tanzania. I argue that the dominant conservation narrative that increased capacity and ‘political will’ for enforcement of marine protected areas (MPAs) reflects a form of spatial fetishization, in that it overemphasizes the influence of space over social behaviour. I contend that Tanzanian MPAs offer bandage solutions to underlying structural problems that are contingent upon the inconsistent availability of social and financial resources for monitoring activities. I suggest that a paradigm shift is necessary, involving the de-territorialization of marine conservation discourse in Tanzania, and a movement towards addressing the underlying social, political and economic conditions that influence marine resource use.
Afficher plus [+] Moins [-]Anticyclonic eddies increase accumulation of microplastic in the North Atlantic subtropical gyre Texte intégral
2018
Brach, Laurent | Deixonne, Patrick | Bradern, Loraline | Durand, Edmée | Desjean, Marie-Christine | Perez, Emile | van Sebille, Erik | ter Halle, Alexandra
There are fundamental gaps in our understanding of the fates of microplastics in the ocean, which must be overcome if the severity of this pollution is to be fully assessed. The predominant pattern is high accumulation of microplastic in subtropical gyres. Using in situ measurements from the 7th Continent expedition in the North Atlantic subtropical gyre, data from satellite observations and models, we show how microplastic concentrations were up to 9.4 times higher in an anticyclonic eddy explored, compared to the cyclonic eddy. Although our sample size is small, this is the first suggestive evidence that mesoscale eddies might trap, concentrate and potentially transport microplastics. As eddies are known to congregate nutrients and organisms, this phenomenon should be considered with regards to the potential impact of plastic pollution on the ecosystem in the open ocean.
Afficher plus [+] Moins [-]Securing a port's future through Circular Economy: Experiences from the Port of Gävle in contributing to sustainability Texte intégral
2018
Carpenter, Angela | Lozano, Rodrigo | Sammalisto, Kaisu | Astner, Linda
Ports are an important player in the world, due to their role in global production and distributions systems. They are major intermodal transport hubs, linking the sea to the land. For all ports, a key requirement for commercial and economic viability is to retain ships using them and to remain accessible to those ships. Ports need to find approaches to help them remain open. They must ensure their continued economic viability. At the same time, they face increasing pressure to become more environmentally and socially conscious. This paper examines the approach taken by the Port of Gävle, Sweden, which used contaminated dredged materials to create new land using principles of Circular Economy. The paper demonstrates that using Circular Economy principles can be a viable way of securing a port's future and contributing to its sustainability, and that of the city/region where it operates.
Afficher plus [+] Moins [-]Dangerous compounds in the dredged material from the sea – Assessment of the current approach to the evaluation of contaminations based on the data from the Polish coastal zone (the Baltic Sea) Texte intégral
2018
Staniszewska, Marta | Boniecka, Helena
It has been shown that the current approach to the assessment of contamination in the sediments obtained during the dredging works in the Baltic countries indicates the presence of "non-contaminated" dredged material. The concentration limits of heavy metals, Polycyclic Aromatic Hydrocarbons (PAHs), Polychlorinated Biphenyls (PCBs) have been exceeded only in 1% of the samples obtained during the dredging works (2005–2015) within the Polish coastal zone. After 2008, no contaminated sediments have been found. Also, in the remaining Baltic countries, sediments are very rarely contaminated. As a result of this assessment, the sediments can be stored in the sea or have a practical application. However, it has been questioned whether the large cost of determining the numerous chemical parameters is justified. It has been proposed to carry out simple screening tests. Following the preliminary screening, the decision on more detailed (and expensive) chemical tests of individual pollutants would be made.
Afficher plus [+] Moins [-]Mercury assessment, macrobenthos diversity and environmental quality conditions in the Salado Estuary (Gulf of Guayaquil, Ecuador) impacted by anthropogenic influences Texte intégral
2018
Calle, Paola | Monserrate, Lorena | Medina, Francisco | Calle Delgado, Madeleine | Tirapé, Ana | Montiel, Marynes | Ruiz Barzola, Omar | Cadena, Omar Alvarado | Dominguez, Gustavo A. | Alava, Juan José
Water and sediment quality, macrobenthos diversity and mercury levels were assessed in the Salado Estuary, Gulf of Guayaquil (Ecuador) during 2008, 2009 and 2014. Severe hypoxia, anoxia and large fluctuations of salinity occurred in an impacted sector within Guayaquil city relative to a mangrove area within the Salado Mangroves Faunal Production Reserve. Significant inter-site and temporal differences were observed for dissolved oxygen, salinity, total dissolved solids, percentage of silts and clays, and species diversity. Macrobenthos' species richness for both sectors was greater during 2008. Sediments revealed high concentrations of total mercury (THg) (1.20–2.76 mg kg−1 dw), exceeding Ecuador's SQG (0.1 mg kg−1 dw). Sediment THg were significantly lower in 2014 than 2008/09. Biota sediment sccumulation factor values for mussels (3.0 to 34), indicate high bioaccumulation potential from mercury-contaminated sediments. This work highlights the need to develop stronger environmental policies to protect the Salado Estuary from anthropogenic stressors.
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