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Resistance of Lophelia pertusa to coverage by sediment and petroleum drill cuttings Полный текст
2013
Allers, Elke | Abed, Raeid M.M. | Wehrmann, Laura M. | Wang, Tao | Larsson, Ann I. | Purser, Autun | De Beer, Dirk
In laboratory experiments, the cold-water coral Lophelia pertusa was exposed to settling particles. The effects of reef sediment, petroleum drill cuttings and a mix of both, on the development of anoxia at the coral surface were studied using O2, pH and H2S microsensors and by assessing coral polyp mortality. Due to the branching morphology of L. pertusa and the release of coral mucus, accumulation rates of settling material on coral branches were low. Microsensors detected H2S production in only a few samples, and sulfate reduction rates of natural reef sediment slurries were low (<0.3nmolScm−3d−1). While the exposure to sediment clearly reduced the coral’s accessibility to oxygen, L. pertusa tolerated both partial low-oxygen and anoxic conditions without any visible detrimental short-term effect, such as tissue damage or death. However, complete burial of coral branches for >24h in reef sediment resulted in suffocation.
Показать больше [+] Меньше [-]Ocean in peril: Reforming the management of global ocean living resources in areas beyond national jurisdiction Полный текст
2013
Gjerde, Kristina M. | Currie, Duncan | Wowk, Kateryna | Sack, Karen
This article presents the outcome of research aimed at assisting governments in meeting their commitments and legal obligations for sustainable fisheries, based on increasing evidence that global fisheries are in crisis. The article assesses the effectiveness of the existing legal and institutional framework for high seas living resources. It focuses on: (1) the role of regional fisheries management organizations (RFMOs); (2) tools for compliance and enforcement to stem illegal fishing; and (3) mechanisms for habitat protection. The article further highlights a variety of options for addressing key weaknesses and gaps in current ocean governance, including United Nations General Assembly (UNGA) resolutions, reforms at the regional level, as well as a possible new legal instrument, with a view to informing international discussions on ways to ensure the sustainable use of high seas resources without compromising the health of the marine environment.
Показать больше [+] Меньше [-]Glophymed: An index to establish the ecological status for the Water Framework Directive based on phytoplankton in coastal waters Полный текст
2013
Romero, I. | Pachés, M. | Martínez-Guijarro, R. | Ferrer, J.
Phytoplankton and its attributes (biomass, abundance, composition, and frequency and intensity of phytoplankton blooms) are essential to establish the ecological status in the Water Frame Directive. The aim of this study is to develop an index “Glophymed” based on all phytoplankton attributes for coastal water bodies according to the directive requirements.It is also developed an anthropogenic pressure index that takes into account population density, tourism, urbanization, industry, agriculture, fisheries and maritime transport for Comunitat Valenciana (Spain).Both indexes (Glophymed and human pressure index) based on a multisampling dataset collected monthly during several years, show a significant statistical correlation (r2 0.75 α<0.01) for typology IIA and (r2 0.93 α<0.01) for typology III–W. The relation between these indexes provides suitable information about the integrated management plans and protection measures of water resources since the Glophymed index is very sensitive to human pressures.
Показать больше [+] Меньше [-]Sources and preservation of organic matter in soils of the wetlands in the Liaohe (Liao River) Delta, North China Полный текст
2013
Lin, Tian | Ye, Siyuan | Ma, Chuanliang | Ding, Xigui | Brix, Hans | Yuan, Hongming | Chen, Yingjun | Guo, Zhigang
Total organic carbon, total nitrogen, δ13Corg, δ15N, and aliphatic and polyaromatic hydrocarbons of fifty-five soil samples collected from the coastal wetlands of the Liaohe Delta were measured, in order to determine the sources and possible preservation of organic matter (OM). The δ15N and δ13Corg values in the samples ranged from 3.0‰ to 9.4‰ and from −30.4‰ to −20.3‰, respectively, implying that the OM in the soils is predominantly derived from C3 plant. The long-chain n-alkanes had a strong odd-over-even carbon number predominance, suggesting a significant contribution from waxes of higher plants. The ubiquitous presence of unresolved complex mixture, alkylated polycylic aromatic hydrocarbons and typical biomarkers of petroleum hydrocarbons (pristane, phytane, hopanes and steranes) indicates that there is a contribution of petroleum hydrocarbons to the organic carbon pool in the wetland soils. P. australis-vegetated wetlands have strong potentials for the preservation of organic carbon in the wetlands.
Показать больше [+] Меньше [-]Marine debris in central California: Quantifying type and abundance of beach litter in Monterey Bay, CA Полный текст
2013
Rosevelt, C. | Los Huertos, M. | Garza, C. | Nevins, H.M.
Monitoring beach litter is essential for reducing ecological threats towards humans and wildlife. In Monterey Bay, CA information on seasonal and spatial patterns is understudied. Central California’s coastal managers require reliable information on debris abundance, distribution, and type, to support policy aimed at reducing litter. We developed a survey method that allowed for trained citizen scientists to quantify the types and abundance of beach litter. Sampling occurred from July 2009–June 2010. Litter abundance ranged from 0.03 to 17.1itemsm−2. Using a mixed model approach, we found season and location have the greatest effect on litter abundance. Styrofoam, the most numerically abundant item, made up 41% of the total amount of litter. Unexpected items included fertilizer pellets. The results of this study provide a baseline on the types and abundance of litter on the central coast and have directly supported policy banning Styrofoam take out containers from local municipalities.
Показать больше [+] Меньше [-]Application of Toxicity Identification Evaluation (TIE) procedures for the characterization and management of dredged harbor sediments Полный текст
2013
Montero, N. | Belzunce-Segarra, M.J. | Gonzalez, J-L. | Menchaca, I. | Garmendia, J.M. | Etxebarria, N. | Nieto, O. | Franco, J.
This study refers to the performance of Phase I Toxicity Identification Evaluation (TIE) procedures to identify the contaminants (i.e. organic compounds, metals and ammonia) exerting toxicity in marine sediments from the Pasaia harbor (Oiartzun estuary, northern Spain). The effectiveness of the manipulations to reduce toxicity was proved with the marine amphipod survival test (whole-sediment) and the sea urchin embryo-larval assay (elutriates).By means of TIEs it was concluded that organic compounds were the major contaminants exerting toxicity, although toxic effects by metals was also demonstrated. Additionally, the combination of Phase I treatments allowed to investigate the toxicity changes associated to the mobility of contaminants during dredging activities. Therefore, the performance of TIE procedures as another line of evidence in the decision-making process is recommended. They show a great potential to be implemented at different steps of the characterization and management of dredged harbor sediments.
Показать больше [+] Меньше [-]Ecotoxicological assessment of sediments from an urban marine protected area (Xixová-Japuí State Park, SP, Brazil) Полный текст
2013
Araujo, G.S. | Moreira, L.B. | Morais, R.D. | Davanso, M.B. | Garcia, T.F. | Cruz, A.C.F. | Abessa, D.M.S.
This study aimed to evaluate the environmental quality of the marine portion of Xixová-Japuí State Park (XJSP), an urban marine protected area, which is influenced by multiple contamination sources, by using ecotoxicological and geochemical analyses. Sediments were predominantly sandy, with low CaCO3 and organic matter contents, and presented contamination by metals (Cd,Cu,Zn). Acute toxicity was detected in three tested samples, and copepod exposed to sediments from four stations exhibited lower fecundities, despite the absence of significant effects. Contamination and toxicity seemed to be associated, suggesting that the environment is degraded and presents risks to the biota. Whole sediment TIE indicated ammonia as a main responsible for toxicity, suggesting sewage is a main contributor to sediment degradation. As external contamination sources seem to be negatively influencing the sediment quality, the park conservation objectives are not being fully reached, demanding actions to mitigate impacts.
Показать больше [+] Меньше [-]A baseline study of levels of mercury, arsenic, cadmium and lead in Northeast Arctic cod (Gadus morhua) from different parts of the Barents Sea Полный текст
2013
Julshamn, Kaare | Duinker, Arne | Nilsen, Bente M. | Frantzen, Sylvia | Maage, Amund | Valdersnes, Stig | Nedreaas, Kjell
This study is one of several baseline studies that will provide basic and reliable information about the content of undesirable substances in important species of fish caught in Norwegian waters. Concentrations of metals in the muscle and liver of more than 800 Northeast Arctic cod caught at 32 sites in the Barents Sea are reported. The highest concentration of both mercury in the muscle and cadmium in the liver was found in cod caught in the western part of the Barents Sea, while the highest concentration of total arsenic was found in cod from the eastern part. The arsenic concentrations varied greatly among individual fish, ranging from 0.3 to 170mgkg−1 wet weight in the muscle. Such high levels of total arsenic have never previously been reported in any fish, and the primary factor for these high concentrations is likely to be the shrimp in the cod diet.
Показать больше [+] Меньше [-]The regrowth of phytoplankton cultures after UV disinfection Полный текст
2013
Martínez, Lucía F. | Mahamud, Manuel M. | Lavín, Antonio G. | Bueno, Julio L.
This study addresses how cultures of three phytoplankton species –Chaetoceros calcitrans, Chlorella autotrophica and Phaeocystis globosa – can recover from the effects of UV-C exposure if the cells are placed in a rich medium. Flow cytometry and pulse amplitude modulation (PAM) were used to determine cell recovery after UV treatment. The recovery of C. calcitrans was complete 9days after treatment. For C. autotrophica, the recovery was noticeable 5days after treatment. P. globosa only recovered if the UV dose did not exceed 7.3×105μWs/cm2. The recovery of the UV-treated cultures introduced to a regrowth medium, compared with the recovery of the irradiated cultures kept in their original environment, had two main characteristics: cell recovery was slower but was more efficient. This pattern of recovery has very important implications for real ballast water management systems because such systems discharge treated water into the environment.
Показать больше [+] Меньше [-]Quantitative analysis of plastic debris on recreational beaches in Mumbai, India Полный текст
2013
Jayasiri, H.B. | Purushothaman, C.S. | Veṇṇilā,
Plastic litter was quantified on four sandy beaches in Mumbai. The mean abundance of 7.49g and 68.83 items per square metre was recorded. The abundance of plastics significantly varied among the beaches showing an increasing trend in the southern part. The abundance of plastics by weight in Dadar was significantly higher than that in Aksa. The size fractionation of plastics proved that small particles (1–20mm) are predominant with 41.85% microplastics (1–5mm) which emphasizes the high risk to marine organisms due to possible ingestion. The highest quantity of microplastics was seen in Juhu beach (55.33%) followed by Versova, Aksa and Dadar. The major contributing factors for the abundance are beach usage for different activities such as recreational, religious and fishing which suggest that the land-based sources provide major inputs to plastic pollution in these beaches.
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