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Baseline aquatic contamination and endocrine status in a resident fish of Biscayne National Park Full text
2017
Bargar, Timothy A. | Whelan, Kevin R.T. | Alvarez, David | Echols, Kathy | Peterman, Paul H.
Surface water, sediment, and fish from Biscayne Bay, coastal wetlands adjacent to the Bay, and canals discharging into the Bay were sampled for determination of baseline contamination in Biscayne National Park. While the number of contaminants detected in canal waters was greater during the wet season than the dry season, no seasonal difference was evident for Biscayne Bay or coastal wetland waters. Estrogen equivalency (as 17β-estradiol equivalents), as predicted by the Yeast Estrogen Screen, for extracts of passive water samplers deployed in canals and wetlands was elevated during the wet relative to the dry season. Generally, contamination in water, sediments, and fish was greater in the canals than in Biscayne Bay and the wetlands. Guideline levels for sediment contaminant were exceeded most frequently in canals relative to the coastal wetlands and the Bay. Further investigation is necessary to better understand the impact of contaminants in Biscayne National Park.
Show more [+] Less [-]Modulation of Spartina densiflora plant growth and metal accumulation upon selective inoculation treatments: A comparison of gram negative and gram positive rhizobacteria Full text
2017
Paredes-Páliz, Karina I. | Mateos-Naranjo, Enrique | Doukkali, Bouchra | Caviedes, Miguel A. | Redondo-Gómez, Susana | Rodríguez-Llorente, Ignacio D. | Pajuelo, Eloísa
Metal contamination of estuaries is a severe environmental problem, for which phytoremediation is gaining momentum. In particular, the associations between halophytes-autochthonous rhizobacteria have proven useful for metal phytostabilization in salt marshes. In this work, three bacterial strains (gram-negative and gram-positive) were used for Spartina densiflora inoculation. All three bacteria, particularly Pantoea strains, promoted plant growth and mitigated metal stress on polluted sediments, as revealed from functionality of the photosynthetic apparatus (PSII) and maintenance of nutrient balance. Pantoea strains did not significantly affect metal accumulation in plant roots, whereas the Bacillus strain enhanced it. Metal loading to shoots depended on particular elements, although in all cases it fell below the threshold for animal consumption. Our results confirm the possibility of modulating plant growth and metal accumulation upon selective inoculation, and the suitability of halophyte-rhizobacteria interactions as biotechnological tools for metal phytostabilization in salt marshes, preventing metal transfer to the food chain.
Show more [+] Less [-]Effects of suspended sediments and nutrient enrichment on juvenile corals Full text
2017
Humanes, Adriana | Fink, Artur | Willis, Bette L. | Fabricius, Katharina E. | De Beer, Dirk | Negri, Andrew P.
Three to six-month-old juveniles of Acropora tenuis, A. millepora and Pocillopora acuta were experimentally co-exposed to nutrient enrichment and suspended sediments (without light attenuation or sediment deposition) for 40days. Suspended sediments reduced survivorship of A. millepora strongly, proportional to the sediment concentration, but not in A. tenuis or P. acuta juveniles. However, juvenile growth of the latter two species was reduced to less than half or to zero, respectively. Additionally, suspended sediments increased effective quantum yields of symbionts associated with A. millepora and A. tenuis, but not those associated with P. acuta. Nutrient enrichment did not significantly affect juvenile survivorship, growth or photophysiology for any of the three species, either as a sole stressor or in combination with suspended sediments. Our results indicate that exposure to suspended sediments can be energetically costly for juveniles of some coral species, implying detrimental longer-term but species-specific repercussions for populations and coral cover.
Show more [+] Less [-]Heavy metal distribution in blood, liver and kidneys of Loggerhead (Caretta caretta) and Green (Chelonia mydas) sea turtles from the Northeast Mediterranean Sea Full text
2017
Yipel, Mustafa | Tekeli, İbrahim Ozan | İşler, Cafer Tayer | Altuğ, Muhammed Enes
The aim of the present study was to determine the concentrations of the most investigated environmentally relevant heavy metals in two highly endangered sea turtle species (Caretta caretta and Chelonia mydas) from the important nesting area on the Northeast Mediterranean Sea. The highest mean concentration was of Fe, while Hg and Pb were lowest. All tissue concentrations of Al, As, Fe and Mn were significantly different between the species. In particular, As, Cd, Cu, Mn, Ni, Se, Zn concentrations were lower in Caretta caretta and Cd, Hg, Mn, Zn concentrations were lower in Chelonia mydas than those reported in other parts of the world. Compared to studies conductud in other parts of the Mediterranean, Cd was lower.
Show more [+] Less [-]Diurnal variation of CO2, CH4, and N2O emission fluxes continuously monitored in-situ in three environmental habitats in a subtropical estuarine wetland Full text
2017
Yang, Wen-Bin | Yuan, Chung-Shin | Tong, Chuan | Yang, Bin | Yang, Lei | Huang, Bang-Qin
Wetlands play a crucial role in modulating atmospheric concentrations of greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The key factors controlling GHG emission from subtropical estuarine wetlands were investigated in this study, which continuously monitored the uptake/emission of GHGs (CO2, CH4, and N2O) by/from a subtropical estuarine wetland located in the Minjiang estuary in the coastal region of southeastern China. A self-designed floating chamber was used to collect air samples on-site at three environmental habitats (Phragmites australis marsh, mudflats, and river water). The CO2, CH4, and N2O concentrations were then measured using an automated nondispersive infrared analyzer. The magnitudes of the CO2 and N2O emission fluxes at the three habitats were ordered as river water>P. australis>mudflats. P. australis emitted GHGs through photosynthesis and respiration processes. Emissions of CH4 from P. australis and the mudflats were revealed to be slightly higher than those from the river water. The total GHG emission fluxes at the three environmental habitats were quite similar (4.68–4.78gm−2h−1). However, when the total carbon dioxide equivalent fluxes (CO2-e) were considered, the river water was discovered to emit the most CO2-e compared with P. australis and the mudflats. Based on its potential to increase global warming, N2O was the main contributor to the total GHG emission, with that emitted from the river water being the most considerable. Tidal water carried onto the marsh had its own GHG content and thus has acted as a source or sink of GHGs. However, water quality had a large effect on GHG emissions from the river water whereas the tidal water height did not. Both high salinity and large amounts of sulfates in the wetlands explicitly inhibited the activity of CH4-producing bacteria, particularly at nighttime.
Show more [+] Less [-]Occurrence and spatial distribution of organophosphorus flame retardants and plasticizers in the Bohai and Yellow Seas, China Full text
2017
Zhong, Mingyu | Tang, Jianhui | Mi, Lijie | Li, Fei | Wang, Runmei | Huang, Guopei | Wu, Huifeng
Seawater samples from 50 sites in the BS and YS were collected to investigate the spatial distribution of 7 OPs. Concentrations of the total OPs (ƩOPs) in the BS and YS ranged from 8.12ngL−1 to 98.04ngL−1 with a geometric mean (GM) of 23.70ngL−1. Tris(1-chloro-2-propyl) phosphate (TCPP) was the dominant compound, followed by tris(2-chloroethyl) phosphate (TCEP) and triphenylphosphine oxide (TPPO). The ƩOPs together with the most commonly detected individual OPs (TCPP, TCEP, tris(1,3-dichloro-2-propyl) phosphate (TDCPP), tri-iso-butyl phosphate (TiBP), triphenyl phosphate (TPhP), and TPPO) tended to decrease from nearshore to offshore and from the surface to the bottom seawaters, indicating major land-based sources. Furthermore, the Yellow Sea Cold Water Mass (YSCWM), Changjiang Diluted Water (CDW), Taiwan Warm Current (TaWC), and Subei Coastal Water (SCW) influenced the horizontal and vertical distributions of the OPs in the study area.
Show more [+] Less [-]Heavy metal concentrations in some gastropods and bivalves collected from the fishing zone of South India Full text
2017
Ragi, A.S. | Leena, P.P. | Cheriyan, Eldhose | Nair, S.M.
The present study investigates heavy metal concentrations in gastropods and bivalves collected from major fishing centers in South India. Three gastropods, Bursa spinosa, Tibia curta, and Murex trapa, and two bivalves, Perna viridis and Villoritta cyprinoids, were collected for the analysis of heavy metals. The metals in the present study followed the order Mg>Ca>Zn>Fe>Cu>Mn>Cr>Pb>Ni>Co>Cd. Trace metal concentrations in the soft tissue of the molluscs varied as follows: for Cd: 0.04–5.33, Co: 0.09–0.87, Cr: 2.18–7.59, Cu: 9.54–37.02, Mn: 1.30–8.50, Ni: 0.94–3.21, Pb: 1.16–2.64 and Zn: 68.16–113.64mgkg−1. Metal concentrations in all the species were below the limits proposed by the World Health Organization, except for Pb and Cd. This baseline study suggests that the levels of toxic metals in M. trapa, T. curta, and B. spinosa should be continuously monitored to assess the fate and effects of these metals in this fragile ecosystem.
Show more [+] Less [-]Determination and speciation of cadmium in microcosms with Bunodosoma caissarum and Perna perna using isotopically enriched 116Cd Full text
2017
Rizzini Ansari, Nafisa | Fernández Iglesias, Nerea | Cordeiro, Renato Campello | Fernandez, Marcos Antônio | Bettmer, Jörg
The study of the uptake and distribution of elements in marine environments is of great interest for understanding their pathways and accumulation. Here, we investigated in laboratory experiments the accumulation behavior of Cd in the sea anemone Bunodosoma caissarum and the mussel Perna perna. Specimens were incubated with isotopically enriched 116Cd in aquariums. Cd concentrations in the seawater and in the tissues of B. caissarum and P. perna were followed by inductively coupled plasma-mass spectrometry (ICP-MS) by means of isotope dilution analysis. Bioconcentration factors for B. caissarum and P. perna exposed to 0.9μg·L−1 of 116Cd were determined to be 80.5 and 850, respectively. P. perna specimens exposed to 4.5μg·L−1 of 116Cd reached 530. Cytosolic proteins associated with Cd from the tissues were extracted and further analyzed by size-exclusion chromatography coupled to ICP-MS. Cd accumulation could be detected in both organisms ranging from high-molecular to low-molecular species.
Show more [+] Less [-]Persistent organochlorine residues in fish and sediments collected from Eastern Aegean coast: Levels, occurrence and ecological risk Full text
2017
Muzyed, Shareef K.I. | Kucuksezgin, Filiz | Tuzmen, Nalan
Organochlorines were determined in fish and sediment collected from Izmir and Çandarlı Bays. The results indicated that ΣCyclodiens were generally predominant contaminants. In all samples, p,p′-DDE was the predominant DDT congener. Aroclors were found in noticeably higher levels than OCPs in sediment and the highest levels of Aroclors, OCPs were found in Nemrut which can be attributed to industrial activities. According to Sediment Quality Guidelines, DDTs were lower than the values that may cause adverse biological risk in sediment samples. Aroclor 1254 in sediments only exceeded the TEL value at Nemrut site. The maximum values of ΣOCPs were found in fish collected from Gülbahçe, while Aroclors were measured in Aliaga. According to related indices, results indicate no recent influxes of DDT in the sampling areas. The estimated daily intake of DDTs, Aroclor1254 were below the acceptable daily intake level recommended by FAO/WHO.
Show more [+] Less [-]Seasonal and spatial variations of marine litter on the south-eastern Black Sea coast Full text
2017
Terzi, Yahya | Seyhan, Kadir
The south-eastern Black Sea coast in Turkey was evaluated for marine litter composition and density covering nine beaches during four seasons. The marine litter (>2cm in size), was collected from the coast and categorized into material and usage categories. The data analysis showed that plastic was the most abundant litter (≥61.65%) by count and weight followed by styrofoam and fabric. The marine litter density ranged from 0.03 to 0.58 with a mean (±SD) of 0.16±0.02 items/m2 by count. Based on weight, it varied between 0.44 and 14.74g/m2 with 3.35±1.63. The east side had a higher marine litter density than the west side with significant differences between beaches. The variations due to different seasons were not significant for any beach. The results of this study should provide baseline information about the coastal marine pollution and will assist the mitigation strategies.
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