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Unravelling the role of zooxanthellae in the uptake and depuration of an essential metal in Exaiptasia pallida; an experiment using a model cnidarian Full text
2015
Hardefeldt, Jannah M. | Reichelt-Brushett, Amanda J.
Coral skeletons record historical trace metal levels in the environment, however, the use of coral skeletal records for biomonitoring studies mostly fail to consider the influence of metal regulation by the living components of coral and subsequent incorporation into the skeleton. This study presents Exaiptasia pallida as a representative of the living components of coral and shows metal partitioning between the tissue and zooxanthellae after chronic exposure to Zn. A strong tendency for preferential accumulation in the zooxanthellae occurred after 32days exposure and Zn concentrations in tissue and zooxanthellae were 123.3±0.7mgkg−1 and 294.9±8.5 respectively. This study shows zooxanthellae density plays an important role in controlling Zn loading in whole anemones and must be considered when investigating metal uptake and loading in zooxanthellate organisms. Further studies that investigate links between aragonite deposition rates and zooxanthellae density and incorporation pathways of metals into skeleton are warranted.
Show more [+] Less [-]Characteristics of marine debris that entangle Australian fur seals (Arctocephalus pusillus doriferus) in southern Australia Full text
2015
Lawson, T.J. | Wilcox, Chris | Johns, Karen | Dann, P. | Hardesty, Britta Denise
Marine debris is a global issue that can have devastating impacts on marine mammals. To understand the types of materials that result in entanglement and thus the potential impact of entangling items on marine wildlife, we analysed data collected from items in which Australian fur seals had been entangled in southern Victoria, Australia over a 15year period. From 1997 to 2012, 138 entangling items were removed from seals. The majority of these entanglements were plastic twine or rope, and seals were entangled in green items more than in any other colour. In general, younger seals were more likely to be entangled than adults. Understanding the effects of marine debris entanglement on the Australian fur seal population can lead to more effective management of the sources of debris and the wildlife that interact with it.
Show more [+] Less [-]The roles of polyculture with Eucheuma gelatinae and Gafrarium tumidum in purification of eutrophic seawater and control of algae bloom Full text
2015
Li, Chunqiang | Yu, Xiaoling | Peng, Ming
To control algae bloom and eutrophication in the tropical semi-closed harbor of the Hongsha Bay in Sanya, China, polyculture systems with macroalgae Eucheuma gelatinae and bivalves Gafrarium tumidum were studied. First, nine polyculture combinations with E. gelatinae and G. tumidum were selected in a pool. Two combinations were then chosen by response surface analysis and used for further study to validate their effect on controlling the microalgae density and reducing the nutrition concentration in the pool. Subsequently, the two selected combinations were used to study the effect on the purification of eutrophic seawater and control of algae bloom in a sea mesocosm. The results indicated that polyculture with E. gelatinae and G. tumidum enhanced the purification of eutrophic seawater and control of algae bloom. These two polyculture combinations are considered suitable for the Hongsha Bay of Sanya in China. The two combinations present an excellent effect on controlling the microalgae density and reducing the nutrition concentration.
Show more [+] Less [-]The Mediterranean non-indigenous ascidian Polyandrocarpa zorritensis: Microbiological accumulation capability and environmental implications Full text
2015
Stabili, Loredana | Licciano, Margherita | Longo, Caterina | Lezzi, Marco | Giangrande, Adriana
We investigated the bacterial accumulation and digestion capability of Polyandrocarpa zorritensis, a non-indigenous colonial ascidian originally described in Peru and later found in the Mediterranean. Microbiological analyses were carried out on homogenates from “unstarved” and “starved” ascidians and seawater from the same sampling site (Adriatic Sea, Italy). Culturable heterotrophic bacteria (22°C), total culturable bacteria (37°C) and vibrios abundances were determined on Marine Agar 2216, Plate Count Agar and TCBS Agar, respectively. Microbial pollution indicators were measured by the most probable number method. All the examined microbiological groups were accumulated by ascidians but differently digested. An interesting outcome is the capability of P. zorritensis to digest allochthonous microorganisms such as coliforms as well as culturable bacteria at 37°C, counteracting the effects of microbial pollution. Thus, the potential exploitation of these filter feeders to restore polluted seawater should be taken into consideration in the management of this alien species.
Show more [+] Less [-]Occurrence and distribution of bisphenol A and alkylphenols in the water of the gulf of Gdansk (Southern Baltic) Full text
2015
Staniszewska, Marta | Koniecko, Iga | Falkowska, Lucyna | Krzymyk, Ewelina
In 2011–2012, the concentrations of bisphenol A (BPA), 4-tert-octylophenol (OP) and 4-nonylphenol (NP) in surface and near-bottom water of the Gulf of Gdansk, as well as inflowing rivers, were similar to those in other regions of Europe; BPA from <5.0 to 277.9ngdm−3, OP from <1.0 to 834.5ngdm−3, and NP from <4.0 to 228.6ngdm−3. The atmospheric transportation of phenol derivatives and their deposition into the water of the gulf was indicated by high enrichment factor values (EF) in the sea surface microlayer in relation to the sub-surface layer.The main route of BPA, OP and NP transportation into the waters of the Gulf of Gdansk is the River Vistula. In spring, significant amounts of bisphenol A and 4-nonylphenol were introduced to the coastal zone with meltwater. The main factors affecting the variability of BPA, OP and NP concentrations in surface and near-bottom water, particularly in summer, were increased tourism in the coastal region, water temperature and dissolved oxygen concentration.
Show more [+] Less [-]Characterization and evolution of the sediments of a Mediterranean coastal lagoon located next to a former mining area Full text
2015
García, Gregorio | Muñoz-Vera, Ana
Coastal lagoons are ecosystems that are relatively enclosed water bodies under the influence of both the terrestrial and the marine environment, being vulnerable to human impacts. Human activities, such as mining extraction, are significant anthropogenic coastal stressors that can negatively affect ecosystems and communities. In light of the above, the objective of this research is to examine the influence of metal mining activities on the composition of sediments of a Mediterranean coastal lagoon, named Mar Menor. This paper presents a comprehensive characterization for grain size, mineralogy, geochemistry and organic matter of sediments of this coastal lagoon, investigating their variation along space and time. Sedimentation dynamics are ruling clearly the grain size predominant in each area of the Mar Menor coastal lagoon, determining the existence of entrainment, transport and sedimentation areas. For minerals, elements and organic matter, sedimentation dynamics are also determining their distribution.
Show more [+] Less [-]Screening for contaminant hotspots in the marine environment of Kuwait using ecotoxicological and chemical screening techniques Full text
2015
Smith, A.J. | McGowan, T. | Devlin, M.J. | Massoud, M.S. | Al-Enezi, M. | Al-Zaidan, A.S. | Al-Sarawi, H.A. | Lyons, B.P.
Kuwait is a country with low rainfall and highly concentrated industrial and domestic effluents entering its coastal waters. These can be both treated and untreated. In this study we sampled a series of coastal and open-sea sites and used a variety of analyses to identify those sites requiring the most attention. We used a high throughput GC–MS screen to look for over 1000 chemicals in the samples. Estrogen and androgen screens assessed the potential to disrupt endocrine activity. An oyster embryo development screen was used to assess biological effect potential.The chemical screen identified sites which had high numbers of identified industrial and domestic chemicals. The oyster screen showed that these sites had also caused high levels of developmental abnormalities with 100% of embryos affected at some sites. The yeast screen showed that estrogenic chemicals were present in outfalls at 2–3ng/l E2 equivalent, and detectable even in some open water sites.
Show more [+] Less [-]Distributions and sources of volatile chlorocarbons and bromocarbons in the Yellow Sea and East China Sea Full text
2015
Yang, Bin | Yang, Gui-Peng | Lu, Xiao-Lan | Li, Li | He, Zhen
Six volatile halogenated organic compounds (VHOC), namely, chloroform, carbon tetrachloride, trichloroethylene, bromodichloromethane, dibromochloromethane, and bromoform, were studied in the Yellow Sea and East China Sea from April to May, 2009. The spatial variability of these VHOC was influenced by various factors, including anthropogenic inputs, biogenic production and complicated hydrographic features such as Changjiang Diluted Water, Yellow Sea Cold Water Mass, and Kuroshio Current. Diurnal study results showed that factors such as solar irradiation, biological activity, and tide affected the abundance of these VHOC. Correlation analyses revealed that bromodichloromethane was positively correlated with chlorophyll a in surface seawater. Principal component analysis suggested that chlorinated compounds like carbon tetrachloride originated from anthropogenic sources whereas brominated compounds such as bromodichloromethane originated from biogenic sources. Sources of other chlorinated and brominated compounds may not be governed by biological processes in the marine environment.
Show more [+] Less [-]Abundance, size and polymer composition of marine microplastics ≥10μm in the Atlantic Ocean and their modelled vertical distribution Full text
2015
Enders, Kristina | Lenz, Robin | Stedmon, Colin A. | Nielsen, Torkel G.
We studied abundance, size and polymer type of microplastic down to 10μm along a transect from the European Coast to the North Atlantic Subtropical Gyre (NASG) using an underway intake filtration technique and Raman micro-spectrometry. Concentrations ranged from 13 to 501itemsm−3. Highest concentrations were observed at the European coast, decreasing towards mid-Atlantic waters but elevated in the western NASG. We observed highest numbers among particles in the 10–20μm size fraction, whereas the total volume was highest in the 50–80μm range. Based on a numerical model size-dependent depth profiles of polyethylene microspheres in a range from 10–1000μm were calculated and show a strong dispersal throughout the surface mixed layer for sizes smaller than 200μm. From model and field study results we conclude that small microplastic is ubiquitously distributed over the ocean surface layer and has a lower residence time than larger plastic debris in this compartment.
Show more [+] Less [-]Sources, concentrations and risk factors of organochlorine pesticides in soil, water and sediment in the Yellow River estuary Full text
2015
Li, Jing | Li, Fadong | Liu, Qiang
The environmental occurrence, sources and risk factors of organochlorine pesticides (HCHs and DDTs) and their isomers or metabolites were studied using comprehensive surveys (including soil, surface water, groundwater and sediment sampling) conducted in the Yellow River Delta (YRD). HCHs and DDTs were all detected in multi environmental media. Compared with reported organochlorine pesticide values in China and abroad and with related environmental quality standards, the concentrations of HCHs and DDTs were generally at low levels in the YRD. Composition of OCPs (DDT metabolites and HCH isomers) showed that DDTs in the multiple environments of the YRD not only came from residues of dicofol but also from atmospheric deposition, while HCH pollution results from the historical usage of a mixture of technical HCH and lindane. Furthermore, the sum of Excess Lifetime Cancer Risk (∑ELCR) exposure to HCHs exceeded the generally acceptable risk level of 1.0E-06 recommended by the USEPA for carcinogenic chemicals.
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