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Marine debris removal: One year of effort by the Georgia Sea Turtle-Center-Marine Debris Initiative
2013
Martin, Jeannie Miller
Once in the marine environment, debris poses a significant threat to marine life that can be prevented through the help of citizen science. Marine debris is any manufactured item that enters the ocean regardless of source, commonly plastics, metal, wood, glass, foam, cloth, or rubber. Citizen science is an effective way to engage volunteers in conservation initiatives and provide education and skill development. The Georgia Sea Turtle Center Marine Debris Initiative (GSTC-MDI) is a grant funded program developed to engage citizens in the removal of marine debris from the beaches of Jekyll Island, GA, USA and the surrounding areas. During the first year of effort, more than 200 volunteers donated over 460h of service to the removal of marine debris. Of the debris removed, approximately 89% were plastics, with a significant portion being cigarette materials. Given the successful first year, the GSTC-MDI was funded again for a second year.
显示更多 [+] 显示较少 [-]Seasonal variation of metal contamination in the barnacles Pollicipes pollicipes in northwest coast of Portugal show clear correlation with levels in the surrounding water
2013
Reis, Pedro A. | Salgado, María Antonia | Vasconcelos, Vitor
The concentrations of metals were determined in northwest (NW) coast of Portugal seawaters and soft tissues of goose barnacles Pollicipes pollicipes. P. pollicipes can be used for monitoring metal contamination in these coastal seawaters, because there were significant correlations (p<0.05) for all metals between soft tissues and seawaters during the four seasons. Metal concentrations in seawaters and P. pollicipes had significant (p<0.05) spatial and seasonal variations and mean log BAFs for Fe and Cd were higher than for Cr, Cu, Mn and Zn. Regarding the metal concentrations obtained in the coastal seawaters, all NW coast of Portugal should be classified as “Class IV – Bad”, except two locations (location 7 at Summer and location 10 at Winter), which should be classified as “Class III – Moderate”. However, considering the metal concentrations bioaccumulated in P. pollicipes, all locations should be classified as “Class III – Remarkably Polluted” during all seasons of 2011.
显示更多 [+] 显示较少 [-]Effectiveness of emetics to study plastic ingestion by Leach’s Storm-petrels (Oceanodroma leucorhoa)
2013
Bond, Alexander L. | Lavers, Jennifer L.
Most plastic ingestion studies rely on dissection of dead birds, which are found opportunistically, and may be biased. We used Leach’s Storm-petrels (Oceanodroma leucorhoa) in Newfoundland to study the effect of dose volume, and the efficacy of emesis using syrup of ipecac as an emetic. Ipecac is a safe method of non-lethally sampling stomach contents, and recovered all ingested plastic. Almost half the storm-petrels sampled had ingested plastic, ranging from 0 to 17 pieces, and weighing 0.2–16.9mg. Using the Ecological Quality Objective for Northern Fulmars, adjusted for storm-petrels smaller size, 43% exceeded the threshold of 0.0077g of plastic. Many adult seabirds offload plastic to their offspring, so storm-petrel chicks likely experience a higher plastic burden than their parents. The ability to study plastic ingestion non-lethally allows researchers to move from opportunistic and haphazard sampling to hypothesis-driven studies on a wider range of taxa and age classes.
显示更多 [+] 显示较少 [-]The effects of mercury on the dynamics of the peracarida community in a temperate coastal lagoon (Ria de Aveiro, Portugal)
2013
Cardoso, P.G. | D’Ambrosio, M. | Marques, S.C. | Azeiteiro, U.M. | Coelho, J.P. | Pereira, E.
This study focuses on the impact of mercury on the dynamics and bioaccumulation patterns of suprabenthic peracarida community along a mercury gradient. Suprabenthic peracarida was negatively affected in terms of biomass, diversity and productivity. Mysids including Mesopodopsis slabberi dominated the community, presenting a regular distribution along the Hg gradient, so are considered tolerant species to mercury. Then, isopods, the second most abundant group, dominated in the most contaminated areas being considered also a tolerant group. Contrarily, amphipods were negatively correlated with higher Hg concentrations, dominating in the intermediate areas, thus are considered more sensitive species. In addition, isopods and amphipods were the taxa with higher mercury body burden, followed by mysids. This paper highlights the importance of suprabenthic peracarida as a vehicle of mercury transference through the estuarine trophic web since it is a main link between benthic and pelagic levels and an essential food resource for numerous fish species.
显示更多 [+] 显示较少 [-]Isotopic signatures of eelgrass (Zostera marina L.) as bioindicator of anthropogenic nutrient input in the western Baltic Sea
2013
Schubert, Philipp R. | Karez, Rolf | Reusch, Thorsten B.H. | Dierking, Jan
Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ15N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows.
显示更多 [+] 显示较少 [-]Risk assessment of the presence of polycyclic aromatic hydrocarbons (PAHs) in coastal areas of Thailand affected by the 2004 tsunami
2013
Pongpiachan, S. | Tipmanee, D. | Deelaman, W. | Muprasit, J. | Feldens, P. | Schwarzer, K.
The total concentrations of twelve, likely carcinogenic, polycyclic aromatic hydrocarbons (PAHs) (i.e., phenanthrene (Phe), anthracene (An), fluoranthene (Fluo), pyrene (Pyr), benz[a]anthracene (B[a]A), chrysene (Chry), benzo[b]fluoranthene (B[b]F), benzo[k]fluoranthene (B[k]F), benzo[a]pyrene (B[a]P), indeno[1,2,3-cd]pyrene (Ind), dibenz[a,h]anthracene (D[a,h]A), and benzo[g,h,i]perylene (B[g,h]P) in backwash deposits of the 2004 Khao Lak tsunami were carefully investigated and compared with the concentrations of world marine sediments (WMS). In general, ∑12PAHs in this study (i.e., 69.43±70.67ngg−1) were considerably lower than those values observed in marine sediments from Boston (54,253ngg−1), coastal sediments from Barcelona Harbour (15,069ngg−1), and riverine sediment from Guangzhou Channel (12,525ngg−1), but were greater than values from coastal sediments in Rosas Bay (12ngg−1), Santa Ponsa Bay (26ngg−1) and Le Planier (34ngg−1). The total toxic benzo[a]pyrene equivalent (TEQCarc) values calculated for Khao Lak coastal sediments (KCS), Khao Lak terrestrial soils (KTS), and Songkhla Lake sediments (SLS) were 10.3±12.2ngg−1, 16.0±47.7ngg−1, and 5.67±5.39ngg−1, respectively. Concentrations of PAHs at all study sites resulted in risk levels that fell into the “acceptable” range of the US EPA model and were much lower than those of other WMS. The cancer risk levels of PAH content in KCS ranged from 7.44×10−8 to 2.90×10−7, with an average of 1.64×10−7±8.01×10−8; this value is 119 times lower than that of WMS. In addition, soil cleanup target levels (SCTLs) for both non-carcinogens (i.e., Phe, An, Fluo and Pyr) and carcinogens (i.e., B[a]A, Chry, B[b]F, B[k]F, B[a]P, Ind, D[a,h]A and B[g,h,i]P) in the KTS samples were estimated for all target groups, with an average value of 115,902±197,229ngg−1.
显示更多 [+] 显示较少 [-]Investigation of heavy metal pollutants at various depths in the Gulf of Izmit
2013
Ergül, Halim Aytekin | Varol, Tolga | Ay, Ümit
In this study, we report results concerning the accumulation of heavy metals in seawater from Izmit Bay. The bay was divided into the three parts: the eastern, the central and the western basins. The goal of this study was to determine levels of heavy metals at various depths in the bay between April 2008 and May 2010. Liquid–liquid extractions were performed on seawater samples. An atomic absorption spectrophotometer was used to measure levels of six metals: lead, cadmium, chromium, iron, manganese and zinc. We applied our results to evaluate the status of pollution in the Gulf of Izmit. Significant seasonal differences in metal concentrations and higher concentrations of many metals in water near the shore are evidence for uncontrolled release of pollutants in the water.
显示更多 [+] 显示较少 [-]Efficient tools for marine operational forecast and oil spill tracking
2013
Marta-Almeida, Martinho | Ruiz-Villarreal, Manuel | Pereira, Janini | Otero, Pablo | Cirano, Mauro | Zhang, Xiaoqian | Hetland, Robert D
Ocean forecasting and oil spill modelling and tracking are complex activities requiring specialised institutions. In this work we present a lighter solution based on the Operational Ocean Forecast Python Engine (OOFε) and the oil spill model General NOAA Operational Modelling Environment (GNOME). These two are robust relocatable and simple to implement and maintain. Implementations of the operational engine in three different regions with distinct oceanic systems, using the ocean model Regional Ocean Modelling System (ROMS), are described, namely the Galician region, the southeastern Brazilian waters and the Texas–Louisiana shelf. GNOME was able to simulate the fate of the Prestige oil spill (Galicia) and compared well with observations of the Krimsk accident (Texas). Scenarios of hypothetical spills in Campos Basin (Brazil) are illustrated, evidencing the sensitiveness to the dynamical system.OOFε and GNOME are proved to be valuable, efficient and low cost tools and can be seen as an intermediate stage towards more complex operational implementations of ocean forecasting and oil spill modelling strategies.
显示更多 [+] 显示较少 [-]Trace metals pollution in seawater and groundwater in the ship breaking area of Sitakund Upazilla, Chittagong, Bangladesh
2013
Hasan, Asma Binta | Kabir, Sohail | Selim Reza, A.H.M. | Zaman, Mohammad Nazim | Ahsan, Mohammad Aminul | Akbor, Mohammad Ahedul | Raśīda, Mohāmmada Māmunura
This study reveals potential accumulation of trace metals in the sea and groundwater due to ship breaking activities which take place along the Bay of Bengal in Sitakund Upazilla, Chittagong, Bangladesh. When compared with WHO and Bangladesh domestic standards for water quality, it is revealed that seawater was strongly polluted by Fe and Hg, moderately by Mn and Al, and slightly by Pb and Cd. Groundwater was strongly polluted by Fe, Pb and Hg, moderately by Mn and Al, and slightly by As. Trace element concentrations of all seawater samples exceeded the average concentration of elements in the Earth’s seawater. The application of Principal Components Analysis identified two sources of pollution–marine and ship breaking. The mechanism of groundwater pollution inferred that if seawater is polluted, nearby groundwater is also polluted with trace metals due to the influence of seawater intrusion.
显示更多 [+] 显示较少 [-]Direct measurement of dissolved N2 and denitrification along a subtropical river-estuary gradient, China
2013
Wu, Jiezhong | Chen, Nengwang | Hong, Huasheng | Lu, Ting | Wang, Longjian | Chen, Zhuhong
The spatial pattern and seasonal variation of denitrification were investigated during 2010–2011 in the Jiulong River Estuary (JRE) in southeast China. Dissolved N2 was directly measured by changes in the N2:Ar ratio. The results showed that excess dissolved N2 ranged from −9.9 to 76.4μmolL−1. Tidal mixing leads to a seaward decline of dissolved gaseous concentrations and water–air fluxes along the river-estuary gradient. Denitrification at freshwater sites varied between seasons, associated with changes in N input and water temperature. The denitrification process was controlled by the nitrate level at freshwater sites, and the excess dissolved N2 observed at the tidal zone largely originated from upstream water transport. Compared to other estuaries, JRE has a relative low gaseous removal efficiency (Ed=12% of [DIN]; annual N removal=24% of DIN load), a fact ascribed to strong tidal mixing, coarse-textured sediment with shallow depth before bedrock and high riverine DIN input.
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