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Bioaccumulation of heavy metals in marine organisms and sediments from Admiralty Bay, King George Island, Antarctica Texte intégral
2016
Trevizani, Tailisi Hoppe | Figueira, Rubens Cesar Lopes | Ribeiro, Andreza Portella | Theophilo, Carolina Yume Sawamura | Majer, Alessandra Pereira | Petti, Mônica Angélica Varella | Corbisier, Thais Navajas | Montone, Rosalinda Carmela
The Antarctic continent is considered a low-impact environment; however, there is a tendency to increase the contaminants' levels due to human activities in the research stations. In this study, As, Cd, Cr, Cu, Hg, Ni, Pb and Zn levels in sediment and biota were determined in the environmental samples from Admiralty Bay (King George Island, Antarctica) collected in 2003. The results demonstrated high concentrations of Cu and Zn in the sediments. There was bioaccumulation of As in the biota from Admiralty Bay and bioaccumulation of Zn specifically in the biota from Martel Inlet. In addition, the results were useful in order to understand the heavy metal levels for the pre-accident condition of Comandante Ferraz Antarctic Station, where an accident occurred in 2012, and also for the comparison with current conditions within the monitoring work developed by INCT-APA (National Institute of Science and Technology for Environmental Research Antarctic).
Afficher plus [+] Moins [-]Incidence of plastic debris in Sooty Tern nests: A preliminary study on Trindade Island, a remote area of Brazil Texte intégral
2016
de Souza Petersen, Elisa | Krüger, Lucas | Dezevieski, Alexandre | Petry, MariaVirginia | Montone, Rosalinda Carmela
Plastic is abundant in the oceans, reaching pelagic zones away from continents. Here we present the first recordings of plastic used as nest material in Sooty Tern nests, on a remote oceanic island. We describe our findings in terms of quantity, size and color of plastic debris. A total of 78 plastics were noted in 54 nests. Four color categories were found: Blue, White, Green and Red. Blue fragments were the most frequent color, present three times as much as white debris. This pattern was present despite blue fragments being smaller and lighter. The plastic debris of lowest frequency were the larger and heavier pieces (red). To our knowledge this is the first record of plastic in Sooty Tern nests. Trindade Island is on an oceanic zone expected to accumulate garbage due to the dynamic ocean currents. Such findings call for a closer inspection of pollution in the Atlantic Ocean.
Afficher plus [+] Moins [-]Variation in characteristics of air concentrations of NH3, NO2 and O3 induced by applications of urea in soils of plastic greenhouses in suburban China Texte intégral
2016
Jiang, Zhaohui | Zeng, Qingru | Pi, Hejie | Tie, Baiqing
Few studies have been carried out so far for measuring concentrations of NH3, NO2 and O3 in plastic greenhouses. In this study, NH3, NO2 and O3 concentrations were measured with passive sampler technology in a plastic greenhouse located in the Changsha suburb in southern China over a one and a half month period (November 30, 2008 to January 11, 2009). Soil in the greenhouse was subjected to four treatment (T) types (no N fertilizer T1, common urea T2, coated urea T3 and common urea with nitrification inhibitor dicyandiamide (DCD) T4. The average concentrations (μg/m3) of NH3, NO2 and O3 in descending order was: T4 (31.66) > T2 (25.93) > T3 (23.52) > T1 (7.96), T2 (10.99) > T3 (8.16) > T4 (7.48) > T1 (5.20), T2 (75.05) > T3 (64.20) > T4 (63.85) > T1 (49.02), respectively. This implied that photochemical reactions took place and that harmful gases accumulated after application of N fertilizer in the plastic greenhouse. DCD inhibited the conversion of ammonium to nitrate, increased NH3 volatilization and decreased NO2 level. The coated urea decreased the emissions of NH3 and increased nitrogen use efficiency. We found significant positive correlations (p < 0.01) between temperature and both NH3 and NO2 levels. Correlations between soil pH and both NH3 and NO2 concentrations were also significant (p < 0.01). The O3 average concentration from March 31, 2009 to April 10, 2009 in the higher latitude of the Yinchuan suburb in northern China was two times greater than that in the Changsha suburb in southern China. The O3 daily concentrations in the Yinchuan suburb exceeded 160 μg/m3 (i.e., China's Grade I standard), and the maximal value 214.83 μg/m3 exceeded 200 μg/m3 (i.e., China's Grade III standard).
Afficher plus [+] Moins [-]Low plastic ingestion rate in Atlantic cod (Gadus morhua) from Newfoundland destined for human consumption collected through citizen science methods Texte intégral
2016
Liboiron, Max | Liboiron, France | Wells, Emily | Richárd, Natalie | Zahara, Alexander | Mather, Charles | Bradshaw, Hillary | Murichi, Judyannet
Marine microplastics are a contaminant of concern because their small size allows ingestion by a wide range of marine life. Using citizen science during the Newfoundland recreational cod fishery, we sampled 205 Atlantic cod (Gadus morhua) destined for human consumption and found that 5 had eaten plastic, an ingestion prevalence rate of 2.4%. This ingestion rate for Atlantic cod is the second lowest recorded rate in the reviewed published literature (the lowest is 1.4%), and the lowest for any fish in the North Atlantic. This is the first report for plastic ingestion in fish in Newfoundland, Canada, a province dependent on fish for sustenance and livelihoods.
Afficher plus [+] Moins [-]Qualitative impact of salinity, UV radiation and turbulence on leaching of organic plastic additives from four common plastics — A lab experiment Texte intégral
2016
Suhrhoff, Tim Jesper | Scholz-Böttcher, Barbara M.
Four common consumer plastic samples (polyethylene, polystyrene, polyethylene terephthalate, polyvinylchloride) were studied to investigate the impact of physical parameters such as turbulence, salinity and UV irradiance on leaching behavior of selected plastic components. Polymers were exposed to two different salinities (i.e. 0 and 35g/kg), UV radiation and turbulence. Additives (e.g. bisphenol A, phthalates, citrates, and Irgafos® 168 phosphate) and oligomers were detected in initial plastics and aqueous extracts. Identification and quantification was performed by GC–FID/MS. Bisphenol A and citrate based additives are leached easier compared to phthalates. The print highly contributed to the chemical burden of the analyzed polyethylene bag. The study underlines a positive relationship between turbulence and magnitude of leaching. Salinity had a minor impact that differs for each analyte. Global annual release of additives from assessed plastics into marine environments is estimated to be between 35 and 917tons, of which most are derived from plasticized polyvinylchloride.
Afficher plus [+] Moins [-]Benthos response following petroleum exploration in the southern Caspian Sea: Relating effects of nonaqueous drilling fluid, water depth, and dissolved oxygen Texte intégral
2016
Tait, R.D. | Maxon, C.L. | Parr, T.D. | Newton, F.C.
The effects of linear alpha olefin (LAO) nonaqueous drilling fluid on benthic macrofauna were assessed over a six year period at a southern Caspian Sea petroleum exploration site. A wide-ranging, pre-drilling survey identified a relatively diverse shelf-depth macrofauna numerically dominated by amphipods, cumaceans, and gastropods that transitioned to a less diverse assemblage dominated by hypoxia-tolerant annelid worms and motile ostracods with increasing depth. After drilling, a similar transition in macrofauna assemblage was observed with increasing concentration of LAO proximate to the shelf-depth well site. Post-drilling results were consistent with a hypothesis of hypoxia from microbial degradation of LAO, supported by the presence of bacterial mats and lack of oxygen penetration in surface sediment. Chemical and biological recoveries at ≥200m distance from the well site were evident 33months after drilling ceased. Our findings show the importance of monitoring recovery over time and understanding macrofauna community structure prior to drilling.
Afficher plus [+] Moins [-]Unmanned vehicles for maritime spill response case study: Exercise Cathach Texte intégral
2016
Dooly, Gerard | Omerdic, Edin | Coleman, Joseph | Miller, Liam | Kaknjo, Admir | Hayes, James | Braga, José | Ferreira, Filipe | Conlon, Hugh | Barry, Hugh | Marcos-Olaya, Jesús | Tuohy, Thomas | Sousa, João | Toal, Dan
This paper deals with two aspects, namely a historical analysis of the use of unmanned vehicles (UAVs ROVs, AUVs) in maritime spill incidents and a detailed description of a multi-agency oil and HNS incident response exercise involving the integration and analysis of unmanned vehicles environmental sensing equipment. The exercise was a first in terms of the level of robotic systems deployed to assist in survey, surveillance and inspection roles for oil spills and harmful and noxious substances.
Afficher plus [+] Moins [-]Elemental composition, distribution and control of biogenic silica in the anthropogenically disturbed and pristine zone inter-tidal sediments of Indian Sundarbans mangrove-estuarine complex Texte intégral
2016
Dhame, Shreya | Kumar, Alok | Ramanathan, AL. | Chaudhari, Punarbasu
Spatial distribution and interrelationship among organic nutrients – silica and carbon – and various lithogenic elements were investigated in the surficial sediments of Matla estuary and Core Zone of Indian Sundarbans Reserve Forest using spatial analysis and multivariate statistics. Biogenic silica (BSi), an important parameter for coastal biogeochemisry, was measured using Si-time alkaline leaching method. BSi concentration ranged from 0.01% to 0.85% with higher concentrations in upstream region of Matla estuary and attenuated values towards the bay, seemingly due to changes in hydrodynamics and land use conditions. Spatial distribution of BSi did not exhibit significant correlation with sediment parameters of organic carbon (OC), elemental composition and clay content. However, it showed significant contrasting trends with total phosphorus (TP) and total silica of human influenced Matla estuary sediments as well as the dissolved silica (DSi) of its surface waters. Anthropogenic influence on sediment geochemistry is discernable with the presence of higher concentrations of organic and inorganic elements in Matla estuary than in Core Zone sediments. Spatial variation trends are often challenging to interpret due to multiple sources of input, varying energy and salinity conditions and constant physical, chemical and biological alterations occurring in the environment. Nonetheless, it is certain that anthropogenic activities have a substantial influence on biogeochemical processes of Sundarbans mangrove-estuarine complex and potentially the coastal ocean.
Afficher plus [+] Moins [-]Assessment of heavy metal pollution in Red River surface sediments, Vietnam Texte intégral
2016
Nguyẽ̂n, Thị Thu Hiè̂n | Zhang, Weiguo | Li, Zhen | Li, Jie | Ge, Can | Liu, Jinyan | Bai, Xuexin | Feng, Huan | Yu, Lizhong
Surface sediment samples were collected from upstream down to the subaqueous delta of the Red River in Vietnam to assess heavy metal pollution. Sediment Cr and V concentrations are strongly correlated with Al, Fe, Mn and total organic carbon concentrations, as well as particle size, suggesting that these two metals are derived primarily from natural sources and enriched in the fine fraction of sediments. In contrast, Cu, Cd, Pb, Ni and Zn concentrations show weaker correlations with particle size, with very high concentrations observed at several sites in the upper reach of the river, pointing to anthropogenic input as a possible source of these heavy metals. Enrichment factors (EF) of Cu, Cd, Pb, Ni and Zn suggest that heavy metal pollution is present in sediments with significantly high values in the upstream. The data analysis indicates that Cd, Cu and Pb are the dominant pollutants in the Red River, with their concentrations reaching moderate to serious pollution levels.
Afficher plus [+] Moins [-]Wave energy level and geographic setting correlate with Florida beach water quality Texte intégral
2016
Feng, Zhixuan | Reniers, Ad | Haus, Brian K. | Solo-Gabriele, Helena M. | Kelly, Elizabeth A.
Many recreational beaches suffer from elevated levels of microorganisms, resulting in beach advisories and closures due to lack of compliance with Environmental Protection Agency guidelines. We conducted the first statewide beach water quality assessment by analyzing decadal records of fecal indicator bacteria (enterococci and fecal coliform) levels at 262 Florida beaches. The objectives were to depict synoptic patterns of beach water quality exceedance along the entire Florida shoreline and to evaluate their relationships with wave condition and geographic location. Percent exceedances based on enterococci and fecal coliform were negatively correlated with both long-term mean wave energy and beach slope. Also, Gulf of Mexico beaches exceeded the thresholds significantly more than Atlantic Ocean ones, perhaps partially due to the lower wave energy. A possible linkage between wave energy level and water quality is beach sand, a pervasive nonpoint source that tends to harbor more bacteria in the low-wave-energy environment.
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