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Metabarcoding approach for the ballast water surveillance – An advantageous solution or an awkward challenge? Полный текст
2015
Zaiko, Anastasija | Martinez, Jose L. | Schmidt-Petersen, Julia | Ribicic, Deni | Samuiloviene, Aurelija | García Vázquez, Eva
Transfer of organisms with ships’ ballast water is recognized as a major pathway of non-indigenous species introduction and addressed in a few recent legislative initiatives. Among other they imply scientific and technical research and monitoring to be conducted in a efficient and reliable way. The recent development of DNA barcoding and metabarcoding technologies opens new opportunities for biodiversity and biosecurity surveillance. In the current study, the performance of metabarcoding approach was assessed in comparison to the conventional (visual) observations, during the en route experimental ballast water survey. Opportunities and limitations of the molecular method were identified from taxonomical datasets rendered by two molecular markers of different degree of universality – the universal cytochrome oxydase sub-unit I gene and a fragment of RuBisCO gene. The cost-efficacy and possible improvements of these methods are discussed for the further successful development and implementation of the approach in ballast water control and NIS surveillance.
Показать больше [+] Меньше [-]Marine debris ingestion by Chelonia mydas (Testudines: Cheloniidae) on the Brazilian coast Полный текст
2015
da Silva Mendes, Sarah | de Carvalho, Robson Henrique | de Faria, Adriana Fonseca | de Sousa, Bernadete Maria
Chelonia mydas is distributed in several regions of the world and they are common in coastal regions and around islands. Between August 2008 and July 2009, 20 specimens of C. mydas were found dead on the beaches of Ubatuba, São Paulo, Brazil. The stomachs were removed and anthropogenic wastes were separated according their malleability and color. Of those animals, nine had ingested marine debris. Soft plastic was the most frequent among the samples and the majority of fragments was white or colorless and was between zero and five cm. Many studies have shown a high incidence of eating waste for some species of sea turtles. The record of ingestion of mostly transparent and white anthropogenic wastes in this study strengthens the hypothesis that these animals mistake them for jellyfish. Although the intake of anthropogenic waste causes impact on the lives of sea turtles, such studies are still scarce in Brazil.
Показать больше [+] Меньше [-]Lead distribution in coastal and estuarine sediments around India Полный текст
2015
Chakraborty, Sucharita | Chakraborty, Parthasarathi | Nath, B Nagender
This study describes the geochemical distribution of lead (Pb) and identifies the critical factors that significantly control Pb distribution and speciation in coastal and estuarine sediments around India by using published data from the literature. Crustal sources influence the abundance of Pb in coastal sediment from the south-east and central-west coast of India. Parts of north-east, north-west, and south-west coast of India were polluted by Pb. Distribution of Pb in sediments, from the north-east and north-west coasts of India, were controlled by Fe–Mn oxyhydroxide mineral phases of the sediments. However, organic carbon (OC) seemed to be a dominant factor in controlling the distribution of Pb in sediments from the central-east and south-west coasts of India. The outcome of this study may help in decision-making to predict the levels of Pb from natural and anthropogenic sources and to control Pb pollution in coastal and estuarine sediments around India.
Показать больше [+] Меньше [-]Assessment of micronuclei induction in peripheral blood and gill cells of some fish species from Aliağa Bay Turkey Полный текст
2015
Çakal Arslan, Özlem | Boyacioğlu, Meltem | Parlak, Hatice | Katalay, Selma | Karaaslan, Muhammet Ali
The aim of this paper was to assess the biological damages in fish caused by various mutagenic agents present in polluted waters of Aliağa Bay. For this purpose, micronuclei (MN) test was performed using peripheral erythrocytes and gill cells of different fish specimens caught from both polluted and relatively clean sites from Aliağa Bay (Turkey). Micronuclei tests is a system of mutagenicity testing used for determining changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells caused by the pollution and chemicals in the environment. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish living in Aliağa Bay at the level of DNA by the means of micronuclei (MN) test. According to the results of present study, frequency of MN was found at high level in polluted site. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regularly monitoring pollution of coastal ecosystem.
Показать больше [+] Меньше [-]Geochemical partitioning of Cu and Ni in mangrove sediments: Relationships with their bioavailability Полный текст
2015
Chakraborty, Parthasarathi | Ramteke, Darwin | Chakraborty, Sucharita
Sequential extraction study was performed to determine the concentrations of non-residual metal-complexes in the mangrove sediments from the Divar Island, (west coast of India). Accumulation of metal in the mangrove roots (from the same location) was determined and used as an indicator of bioavailability of metal. An attempt was made to establish a mechanistic linkage between the non-residual metal complexes and their bioavailability in the mangrove system. The non-residual fractions of Cu and Ni were mainly associated with Fe/Mn oxyhydroxide and organic phases in the sediments. A part of these metal fractions were bioavailable in the system. These two phases were the major controlling factors for Ni speciation and their bioavailability in the studied sediments. However, Cu was found to interact more strongly with the organic phases than Ni in the mangrove sediments. Organic phases in the mangrove sediments acted as buffer to control the speciation and bioavailability of Cu in the system.
Показать больше [+] Меньше [-]Secondary production of the fiddler crab Uca rapax from mangrove areas under anthropogenic eutrophication in the Western Atlantic, Brazil Полный текст
2015
de M. M. Costa, Tarso | Soares-Gomes, Abilio
Fiddler crabs Uca rapax were analyzed in three mangrove areas located in both a lagoon and estuarine system in order to study the influence of eutrophication on their population dynamics and production. Populations at the three sites showed a biased sex ratio. Densities were similar at the three sites, but biomass was higher at the lagoon system. Despite biomass being higher at the most eutrophic site, this site exhibited the lowest production. Regarding age structure, the population inhabiting the less eutrophic site mainly comprised younger crabs. The lower production and smaller P/B ratio found in the more eutrophic site were most likely consequences of a high mortality rate and an aged population. Our study evidences the high plasticity of the fiddler crab U. rapax, and confirms secondary production and P/B ratio estimates as useful tools to assess the effects of environmental change.
Показать больше [+] Меньше [-]Distribution, sources, and fluxes of heavy metals in the Pearl River Delta, South China Полный текст
2015
Geng, Junjie | Wang, Yiping | Luo, Hanjin
Riverine samples were collected at various locations in the Pearl River Delta (PRD) to determine the concentrations of heavy metals (Cr, Ni, Cu, Mn, Zn, Cd, and Pb) in time and space and to estimate the fluxes of heavy metals to the coastal waters off South China. Most of the elements exhibit clear temporal and spatial trends. Principal component analysis shows that surface erosion is the major factor affecting metal concentrations in particulates in the PRD. Natural geology is an important source of these heavy metals. The annual fluxes of Cr, Ni, Cu, Mn, Zn, Cd, and Pb in upstream and downstream were 445, 256, 241, 3293, 1279, 12, and 317t/year and 1823, 1144, 1786, 15,634, 6183, 74, and 2017t/year, respectively. A comparison indicated that the annual fluxes of Mn accounted for 1.3% of the global river fluxes, whereas other elements contribute <1%.
Показать больше [+] Меньше [-]Temporal variability of marine debris deposition at Tern Island in the Northwestern Hawaiian Islands Полный текст
2015
Agustin, Alyssa E. | Merrifield, Mark A. | Potemra, James T. | Morishige, Carey
A twenty-two year record of marine debris collected on Tern Island is used to characterize the temporal variability of debris deposition at a coral atoll in the Northwestern Hawaiian Islands. Debris deposition tends to be episodic, without a significant relationship to local forcing processes associated with winds, sea level, waves, and proximity to the Subtropical Convergence Zone. The General NOAA Operational Modeling Environment is used to estimate likely debris pathways for Tern Island. The majority of modeled arrivals come from the northeast following prevailing trade winds and surface currents, with trajectories indicating the importance of the convergence zone, or garbage patch, in the North Pacific High region. Although debris deposition does not generally exhibit a significant seasonal cycle, some debris types contain considerable 3cycle/yr variability that is coherent with wind and surface pressure over a broad region north of Tern.
Показать больше [+] Меньше [-]Organophosphorous flame retardants in biota from Svalbard, Norway Полный текст
2015
Hallanger, Ingeborg G. | Sagerup, Kjetil | Evenset, Anita | Kovacs, Kit M. | Leonards, Pim | Fuglei, Eva | Routti, Heli | Aars, Jon | Strøm, Hallvard | Lydersen, Christian | Gabrielsen, Geir Wing
Eight arctic species, including fish, birds and mammals, from diverse habitats (marine and terrestrial) within the Svalbard Archipelago, Norway, were screened for 14 organophosphorus flame retardant (PFR) compounds. Ten PFRs were detected: tris(2-chloroethyl)phosphate (TCEP), tris(2-chloroisopropyl)phosphate (TCIPP), tris(1,3-dichloro-2-propyl)phosphate (TDCIPP), triphenyl phosphate (TPHP); 2-ethylhexyl diphenyl phosphate (EHDPP); tris(2-butoxyethyl)phosphate (TBOEP); tritolyl phosphate (TCrP); triisobutyl phosphate (TIBP); tris(2-ethylhexyl)phosphate (TEHP); and butyl diphenyl phosphate (DPhBP). The greatest number of different PFR compounds, and the highest detection frequency were measured in capelin (Mallotus villotus), and the lowest in Brünnich's guillemot (Uria lomvia). The highest concentrations of ΣPFR, as well as the highest concentration of a single PFR compound, TBOEP, were measured in arctic fox (Vulpes lagopus). The presence of PFR compounds in arctic biota indicates that these compounds can undergo long-range transport and are, to some degree, persistent and bioaccumulated. The potential for biomagnification from fish to higher trophic levels seems to be limited.
Показать больше [+] Меньше [-]Entrenching environmental obligation in marine regulation Полный текст
2015
Wakefield, Jill
The institutional frameworks addressing issues in connection with the marine commons agreed by States are set out in the 1982 UN Convention on the Law of the Sea, which is the basis of the European Union’s common fisheries policy. Despite a substantial body of environmental legislation, provisions concerning the protection of ecosystems and bioversity have not been incorporated into any international measure or EU to control fishing, leading to ecosystem degradation. Regulation should impose the responsibility for rectifying damage to fish stocks and ecosystems as a result of fishing activity on the fishing industry.
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