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Assessment of a coastal lagoon metal distribution through natural and anthropogenic processes (SE, Brazil) Full text
2019
Beraldi, Gaby Quintal F. | de Rezende, Carlos Eduardo | de Almeida, Marcelo Gomes | Carvalho, Carla | Lacerda, Luiz Drude de | de Farias, Roberto Nascimento | Vidal, Marcella | Souza, Michael Douglas P. | Molisani, Mauricio Mussi
The present study intends to assess the metal pollution of a eutrophic coastal lagoon, analyzing the long-term and actual metal content in surface sediments, suspended particles, aquatic macrophyte and fish species, and the loads emitted from natural processes and anthropogenic sources, including the relative emission of domestic untreated sewage. Distribution indicated contamination of suspended particles with Cd and the predominance of Pb in the bioavailable form in surface sediments which may explain Cd and Pb contamination in fish. Domestic untreated sewage was an important source of Cu and due to the lagoon's management, this source may be increasing the metal content in the lagoon's surface sediments. Soil loss, atmospheric deposition and solid waste disposal also contributed to metal inputs to the lagoon. Extensive contamination has been prevented by the lagoon's management such as sandbar opening. Metal retention within the watershed soils reduce the effective metal transference and lagoon pollution.
Show more [+] Less [-]PCDD/F and PCB levels in different tissues from dugongs (Dugong dugon) inhabiting the Queensland coastline Full text
2019
Vijayasarathy, S. | Weijs, L. | Grant, S. | Gallen, M. | Gaus, C.
Previous studies on PCDD/Fs and PCBs in dugong (Dugong dugon) blubber reported unexpectedly elevated TEQ levels. This study analysed archived blubber, muscle, liver and faeces obtained from dugongs from two areas along the Queensland coast. All samples showed detectable levels of PCDDs and PCBs, while PCDFs were consistently near or below LOQ. PCDD levels in dugongs contributed to a large proportion (<95%) of sum TEQ levels in all tissues (blubber: 6.7–38 pg g−1 lw, muscle: 5.7–96 pg g−1 lw, liver: 3.3–42 pg g−1 lw, faeces: 203 pg g−1 lw). Liver/blubber tissue ratios show that PCDDs are preferentially accumulated in the liver with higher degree of chlorination. The same trend was not so obvious with PCBs, which occasionally showed higher hepatic sequestration of lower chlorinated PCBs such as PCBs 28 and 77. PCDD congeners were dominated by OCDD which is similar to the profiles from the dugongs' food source, namely sediment and seagrass.
Show more [+] Less [-]Post-release breeding success of oil-rehabilitated and non-rehabilitated little blue penguins, Eudyptula minor, following the M/V Rena oil spill, New Zealand Full text
2019
Sievwright, Karin A. | Battley, Phil F. | McConnell, Helen M. | Chilvers, B. L. (Barbara Louise) | Morgan, Kerri J.
During the 2011 M/V Rena oil spill in Tauranga, New Zealand, 383 little blue penguins (LBP, Eudyptula minor) were oiled, rescued and rehabilitated, with 90.6% surviving to be released back to the wild. We monitored the post-release breeding success of rehabilitated LBPs to assess the effectiveness of the rehabilitation process. Breeding success was monitored during the first breeding season post-release (2012−13) to assess productivity for both rehabilitated and control penguins (breeding pairs of rehabilitated or non-oiled (control) birds). Egg laying, hatching and fledging success rates for pairs of rehabilitated and control penguins were both within ranges reported for other LBP colonies in Australia and New Zealand. The only significant difference between rehabilitated and control pairs was that hatching success was reduced in the first season after release for rehabilitated pairs. Overall, rehabilitation appeared to reverse most potential negative effects of oiling on the post-release breeding success of rehabilitated LBP.
Show more [+] Less [-]Arctic marine fish ‘biotransformation toxicity’ model for ecological risk assessment Full text
2019
Fahd, Faisal | Veitch, Brian | K̲h̲ān, Faiṣal
Oil and gas exploration and marine transport in the Arctic region have put the focus on the ecological risk of the possibly exposed organisms. In the present study, the impacts of sea ice, extreme light regime, various polar region-specific physiological characteristics in polar cod (Boreogadus saida) and their effects on xenobiotic distribution and metabolism are studied. A Bayesian belief network is used to model individual fish toxicity. The enzyme activity in the fish liver and other pertinent organs is used as a proxy for cellular damage and repair and is subsequently linked to toxicity in polar cod. Seasonal baseline variation in enzyme production is also taken into consideration. The model estimates the probability of exposure concentration to cause cytotoxicity and circumvents the need to use the traditionally obtained No Observed Effect Concentration (NOEC). Instead, it uses biotransformation enzyme activity as a basis to estimate the probability of individual cell damages.
Show more [+] Less [-]Insight into tidal disturbance on colonization surveys for marine bioassessment using periphytic ciliates based on biological trait analysis Full text
2019
Zhong, Xiaoxiao | Xu, Guangjian | Min, Gi-Sik | Kim, Sanghee | Xu, Henglong
To understand tidal disturbance on the colonization dynamics in community functioning of the ciliates in marine ecosystems, a 1-month survey was conducted using the conventional slide system (CS) and the polyurethane foam enveloped slide system (PFES) in Korean coastal waters. The results showed considerable differences were detected in community functioning parameters between the two systems. The vagile, flattened forms feeding on periphytic microalgae showed a higher community-weighted mean (CWM) value, and the solitary-colonial pattern represented a more stable temporal variability during the colonization in the PFES system than the CS system. The temporal shift in community functioning of the ciliates showed different ways in both systems. The functional diversity measures generally levelled off at more stable values in the communities with ages of 13–15 days in the PFES system than the CS system. These results imply that the PFES system may be a workable method for bioassessment in marine ecosystems.
Show more [+] Less [-]Introductions and transfers of species by ballast water in the Adriatic Sea Full text
2019
Gollasch, Stephan | Hewitt, Chad L. | Bailey, Sarah | David, Matej
Following the Editorial addressing the BALMAS project, we open the ballast water management special issue for the Adriatic Sea by providing background information on non-indigenous species and the mechanisms (vectors) of transport. Problems allocating introduction mechanisms for various species with certainty are described; in general, key introduction mechanisms are shipping, with ballast water and biofouling as dominant vectors, and aquaculture activities. The dominant mechanisms for introduction may differ through time, between regions and across species. We highlight ballast water as the focus of an international convention to prevent future introductions, reviewing management options and suggesting future research needs. This assessment is not restricted in application to the Adriatic Sea, but is applicable to other coastal waters. Results of such future work may contribute to the experience building phase planned by the International Maritime Organization for a harmonised implementation of the Ballast Water Management Convention.
Show more [+] Less [-]Where else? Assessing zones of alternate ballast water exchange in the Canadian eastern Arctic Full text
2019
Goldsmit, Jesica | Nudds, Shannon Hope | Stewart, D Bruce | Higdon, Jeff Wayde | Hannah, Charles Gordon | Howland, Kimberly Lynn
Mid-ocean ballast water exchange (BWE) is recommended for international vessels to minimize the transfer of nonindigenous species (NIS). When this cannot be accomplished due to safety concerns, alternate ballast water exchange zones (ABWEZ) may be used. A coupled-ice-ocean model with meteorological forcing and particle tracking was used to evaluate the relative risks from BWE along primary shipping routes into Canada's eastern Arctic. Relative risk to receiving habitats from BWE was calculated from the product of likelihood of exposure, likelihood of establishment, and habitat sensitivity to potential NIS. Modelling results indicate that existing ABWEZs in and around Lancaster Sound and Hudson Strait are among the areas of highest relative risk for introductions of NIS via ballast water. The deeper offshore regions of Labrador Sea and Baffin Bay should be considered as alternatives. However, further research is recommended to assess the risks of NIS associated with BWE in the Canadian Arctic.
Show more [+] Less [-]Trace element concentrations, ecological and health risk assessment in sediment and marine fish Otolithes ruber in Oman Sea, Iran Full text
2019
Sadeghi, Parvin | Loghmani, Mehran | Afsa, Elahe
This study aimed to investigate the concentration of Cd, Ni, Cr, Pb and As in the tissues of Otolithes ruber and surface sediments in the Oman Sea. Trace element concentrations were analyzed by flame atomic absorption spectrophotometer (FAAS) for ecological and health risk assessment. The results showed a significant difference in trace element concentrations of the liver, muscle and sediments between different stations (p < 0.05). Potential ecological risk index (PER) indicated very high risk for Cd at all stations. Estimated daily intake (EDI) for consumption of Otolithes ruber for Cr, Pb and As was lower than tolerable daily intake (TDI). The mean target hazard quotient (THQ) of Cd and Ni were higher than 1 at all stations. Target cancer risk (TR) for Ni and As were higher than the acceptable value range at all stations. Accordingly, the risk of cancer due to the long-term consumption of this fish can be concerned.
Show more [+] Less [-]Marine debris at nesting grounds used by the Northern Gulf of Mexico loggerhead recovery unit Full text
2019
Garrison, Samantha R. | Fuentes, Mariana M.P.B.
Anthropogenic marine debris (AMD) can cause obstructions for nesting marine turtles and hatchlings, increase their exposure to toxicants, and potentially alter the incubating environment of clutches. Given the potential impacts of AMD on marine turtles, this study provides baseline information on the abundance and distribution of AMD at the ten highest density nesting beaches in Florida used by the Northern Gulf of Mexico Loggerhead Recovery Unit. Monitoring for AMD at nesting beaches was conducted in 2017 following protocols from the International Coastal Cleanup. AMD was present at all the nesting beaches, with the majority of AMD observed at the westernmost sites beginning with St. Joseph Peninsula State Park (363 AMD/km) with a gradual decrease of abundance to the easternmost site, Alligator Point (16 AMD/km). Plastic and foam items accounted for 92% (n = 13,566) of all AMD found.
Show more [+] Less [-]Accumulation and distribution of marine debris on barrier islands across the northern Gulf of Mexico Full text
2019
Wessel, Caitlin | Swanson, Kathleen | Weatherall, Tracy | Cebrian, Just
Marine debris is an economic, environmental, human health, and aesthetic problem posing a complex challenge to communities around the globe. To better document this problem in the Gulf of Mexico we monitored the occurrence and accumulation rate of marine debris at twelve sites on nine barrier islands from North Padre Island, Texas to Santa Rosa, Florida. With this information we are investigating three specific questions: (1) what are the major types/sources of marine debris; (2) does debris deposition have seasonal oscillations; and (3) how does debris deposition change spatially? Several trends emerged; plastic composed 69–95% of debris; there was a significant increase in debris accumulation during the spring and summer seasons; accumulation rates were ten times greater in Texas than the other Gulf States throughout the year; and the amount of debris accumulating along the shoreline could be predicted with high confidence in areas with high freshwater influx.
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