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Metal concentrations in demersal fish species from Santa Maria Bay, Baja California Sur, Mexico (Pacific coast) Texto completo
2015
Jonathan, M.P. | Aurioles-Gamboa, David | Villegas, Lorena Elizabeth Campos | Bohórquez-Herrera, Jimena | Hernández-Camacho, Claudia J. | Sujitha, S.B.
Concentrations of 11 trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, As, Hg) in 40 fish species from Santa Maria Bay, Baja California Sur, Mexico, the strategically important area for marine mammals and organisms were analyzed. Based on their concentrations the ranking of metals Fe>Zn>Ni>Cr>Mn>Pb>Cu>Co>As>Cd>Hg suggests that organism size, metabolism and feeding habits are correlated with metal concentrations. Local geological formations affect the concentrations of different metals in the aquatic environment and are subsequently transferred to fishes. The correlation analysis suggests that metabolism and nurturing habits impact the concentration of metals. Concentrations of Fe and Mn appear to be influenced by scavenging and absorption processes, which vary by species. The considerable variability in the metal concentrations obtained in different species underscores the importance of regular monitoring.
Mostrar más [+] Menos [-]Impact of CO2-driven acidification on the development of the sea cucumber Apostichopus japonicus (Selenka) (Echinodermata: Holothuroidea) Texto completo
2015
Yuan, Xiutang | Shao, Senlin | duPont, Sam | Meng, Leiming | Liu, Yongjian | Wang, Lijun
Impact of CO2-driven acidification on the development of the sea cucumber Apostichopus japonicus (Selenka) (Echinodermata: Holothuroidea) Texto completo
2015
Yuan, Xiutang | Shao, Senlin | duPont, Sam | Meng, Leiming | Liu, Yongjian | Wang, Lijun
We evaluated the impact of ocean acidification on the early development of sea cucumber Apostichopus japonicus. The effect of pH-levels (pH 8.04, 7.85, 7.70 and 7.42) were tested on post-fertilization success, developmental (stage duration) and growth rates. Post-fertilization success decreased linearly with pH leading to a 6% decrease at pH 7.42 as compared to pH 8.1. The impact of pH on developmental time was stage-dependent: (1) stage duration increased linearly with decreasing pH in early-auricularia stage; (2) decreased linearly with decreasing pH in the mid-auricularia stage; but (3) pH decline had no effect on the late-auricularia stage. At the end of the experiment, the size of doliolaria larvae linearly increased with decreasing pH. In conclusion, a 0.62 unit decrease in pH had relatively small effects on A. japonicus early life-history compared to other echinoderms, leading to a maximum of 6% decrease in post-fertilization success and subtle effects on growth and development.
Mostrar más [+] Menos [-]Impact of CO2-driven acidification on the development of the sea cucumber Apostichopus japonicus (Selenka) (Echinodermata: Holothuroidea) Texto completo
2015
Yuan, Xiutang | Shao, Senlin | Dupont, Sam | Meng, Leiming | Liu, Yongjian | Wang, Lijun
We evaluated the impact of ocean acidification on the early development of sea cucumber Apostichopus japonicus. The effect of pH-levels (pH 8.04, 7.85, 7.70 and 7.42) were tested on post-fertilization success, developmental (stage duration) and growth rates. Post-fertilization success decreased linearly with pH leading to a 6% decrease at pH 7.42 as compared to pH 8.1. The impact of pH on developmental time was stage-dependent: (1) stage duration increased linearly with decreasing pH in early-auricularia stage; (2) decreased linearly with decreasing pH in the mid-auricularia stage; but (3) pH decline had no effect on the late-auricularia stage. At the end of the experiment, the size of doliolaria larvae linearly increased with decreasing pH. In conclusion, a 0.62 unit decrease in pH had relatively small effects on A. japonicus early life-history compared to other echinoderms, leading to a maximum of 6% decrease in post-fertilization success and subtle effects on growth and development.
Mostrar más [+] Menos [-]Loss of native rocky reef biodiversity in Australian metropolitan embayments Texto completo
2015
Stuart-Smith, Rick D. | Edgar, Graham J. | Stuart-Smith, Jemina F. | Barrett, Neville S. | Fowles, Amelia E. | Hill, Nicole A. | Cooper, Antonia T. | Myers, Andrew P. | Oh, Elizabeth S. | Pocklington, Jacqui B. | Thomson, Russell J.
Urbanisation of the coastal zone represents a key threat to marine biodiversity, including rocky reef communities which often possess disproportionate ecological, recreational and commercial importance. The nature and magnitude of local urban impacts on reef biodiversity near three Australian capital cities were quantified using visual census methods. The most impacted reefs in urbanised embayments were consistently characterised by smaller, faster growing species, reduced fish biomass and richness, and reduced mobile invertebrate abundance and richness. Reef faunal distribution varied significantly with heavy metals, local population density, and proximity to city ports, while native fish and invertebrate communities were most depauperate in locations where invasive species were abundant. Our study adds impetus for improved urban planning and pollution management practises, while also highlighting the potential for skilled volunteers to improve the tracking of changes in marine biodiversity values and the effectiveness of management intervention.
Mostrar más [+] Menos [-]Interpretation of coastal sediment quality based on trace metal and PAH analysis, benthic foraminifera, and toxicity tests (Sardinia, Western Mediterranean) Texto completo
2015
Schintu, Marco | Buosi, Carla | Galgani, François | Marrucci, Alessandro | Marras, Barbara | Ibba, Angelo | Cherchi, A. (Antonietta)
An integrated approach for the assessment of coastal sediment quality was utilised in three areas of Sardinia (Western Mediterranean, Italy). Sediments were analysed for trace metals and polycyclic aromatic hydrocarbons (PAHs), while benthic foraminifera were used as bioindicators. Furthermore, the embryo-toxicity test was used to provide ecologically relevant information using rapid and cost-effective screening tools. The aim was to evaluate the usefulness of coupling different analytical tools. The results revealed the presence of polluted sediments in areas exposed to petrochemical industries, smelters or military settlements. However, while foraminifera have presented similar indications for chemical analysis of contamination levels in the different areas, the toxicity test exhibited a poor relationship with the contaminants measured individually. The results raise questions concerning the bioavailability of contaminants released by sediments in the water column. Overall, the toxicity rate was significant in many samples in comparison with other sites studied in other Mediterranean regions.
Mostrar más [+] Menos [-]Pyrolysis–gas chromatography–mass spectrometry with electron-ionization or resonance-enhanced-multi-photon-ionization for characterization of polycyclic aromatic hydrocarbons in the Baltic Sea Texto completo
2015
Otto, Stefan | Streibel, Thorsten | Erdmann, Sabrina | Klingbeil, Sophie | Schulz-Bull, Detlef | Zimmermann, Ralf
Polycyclic aromatic hydrocarbons (PAH), as a part of dissolved organic matter (DOM), are environmental pollutants of the marine compartment. This study investigates the origin of PAH, which is supposed to derive mainly from anthropogenic activities, and their alteration along the salinity gradient of the Baltic Sea. Pyrolysis in combination with gas chromatography and two mass selective detectors in one measurement cycle are utilized as a tool for an efficient trace analysis of such complex samples, by which it is possible to detect degradation products of high molecular structures. Along the north–south transect of the Baltic Sea a slightly rising trend for PAH is visible. Their concentration profiles correspond to the ship traffic as a known anthropogenic source, underlined by the value of special isomer ratios such as phenanthrene and anthracene (0.31–0.45) or pyrene and fluoranthene (0.44–0.53). The detection of naphthalene and the distribution of its alkylated representatives support this statement.
Mostrar más [+] Menos [-]Histopathology and contaminant concentrations in fish from Kuwait’s marine environment Texto completo
2015
Al-Zaidan, A.S. | Al-Sarawi, H.A. | Massoud, M.S. | Al-Enezi, M. | Smith, A.J. | Bignell, J.P. | Green, M.J. | Askem, C. | Bolam, T.P.C. | Barber, J.L. | Bersuder, P. | Lyons, B.P.
Kuwait has witnessed major socioeconomic and industrial development in recent decades. Consequently, a variety of contaminants related to these activities have been discharged directly into the marine environment. This paper describes the application of a histopathology baseline survey in two potential sentinel species, the Giant sea catfish (Arius thalassinus) and the Fourlined terapon (Pelates quadrilineatus) to assess the health of biota inhabiting Kuwait’s marine environment. Histological analysis revealed several lesion types in both species, although the prevalence was generally considered low with no discernible differences between sampling locations. The analysis of contaminant burdens (metals, PCBs, PBDEs, HBCDD) in A. thalassinus, along with the analysis of bile for PAH metabolites in both species, indicated that levels of contaminant exposure was low. Overall the data show that both species appear to be susceptible to pathologies associated with environmental contaminants and therefore suitable for further investigation as sentinel organisms for biological effects monitoring.
Mostrar más [+] Menos [-]Distribution and ecotoxicology of bioavailable metals and As in surface sediments of Paraguaçu estuary, Todos os Santos Bay, Brazil Texto completo
2015
Pereira, Taís de S. | Moreira, Ícaro T.A. | de Oliveira, Olívia M.C. | Rios, Mariana C. | Filho, Wilton A.C.S. | de Almeida, Marcos | de Carvalho, Gilson Correia
Surface sediments collected in the intertidal zone of Paraguaçu estuary in July, 2013, were analyzed for organic matter, nitrogen, phosphorus, grain size fractions and partial concentrations of 16 metals. The USEPA 3051A method and ICP-OES and CV-AAS techniques were chosen to metal analysis. Pollution indices (EF, Igeo and PIN) and a comparison with sediment quality guidelines (UET, ERL, ERM, TEL and PEL of NOAA) were conducted in order to evaluate the potential metal impacts over the area. Principal Component Analysis (PCA) and Pearson correlation results showed the importance of organic matter content and the fine-grained fraction of sediments on the control of the bioavailable metals distribution. The Paraguaçu estuary already has anthropogenic enrichment relative to the background level, especially for Mn, whose values exceeded almost 30 times the background at one site (Mn: 1197.30mgkg−1). However, metal levels are still below the reference values with the exception of Hg at one site (Hg: 0.25mgkg−1, exceeded TEL and ERL).
Mostrar más [+] Menos [-]Dissecting the distribution of brittle stars along a sewage pollution gradient indicated by organic markers Texto completo
2015
Barboza, Carlos Alberto de Moura | Martins, César C. | Lana, Paulo da Cunha
We have assessed variation in brittle star distribution patterns along a contamination gradient identified by fecal steroids and aliphatic hydrocarbons in Paranaguá Bay, southern Brazil. A hierarchical design using multiple spatial scales (centimeters-kilometers) was applied. Generalized linear mixed models (GLMMs) were used to investigate the spatial and temporal variability of brittle stars. Main principal components from the contamination and environmental matrices were used to investigate the best explanatory dataset. The abundance of brittle stars was significantly lower in sites with high concentrations of fecal steroids and aliphatic hydrocarbons. The best model fitting always included components from the contamination gradients, which precludes a purely environmental driving of brittle star abundance. Variability in spatial scales lower than kilometers was probably driven by sediment characteristics. We highlighted the importance of a robust multi-scale sampling design for a better biological indication of coastal contamination.
Mostrar más [+] Menos [-]Assessment of bioavailability and potential toxicity of Cu, Zn and Pb, a case study in Jurujuba Sound, Rio de Janeiro, Brazil Texto completo
2015
Abuchacra, P.F.F. | Aguiar, V.M.C. | Abuchacra, R.C. | Baptista Neto, J.A. | Oliveira, A.S.
Potential toxicity of sedimentary Cu, Zn and Pb were evaluated based on their fractionation at the inner part of Jurujuba, a small sound at the eastern margin of Guanabara Bay, Rio de Janeiro. Biogeochemical composition revealed an environment extremely enriched with anthropic organic matter and characterized as a detrital heterotrophic system. The fractionation analysis showed that Pb exhibited more affinity with the residual fraction followed by the amorphous Fe/Mn fraction. Cu and Zn were more expressive in the amorphous Fe/Mn fraction followed by the organic one and crystalline Fe/Mn fraction, respectively. According to Igeo index, sediments proved to be highly polluted by Zn and Cu and moderated polluted by Pb. Despite the actual contamination of Jurujuba sediments, the mobility of these elements seems to be limited since the most excessive concentrations were found in the less available fractions, depending on extreme physico-chemical variations to be released.
Mostrar más [+] Menos [-]Variations in macrobenthic community structures in relation to environmental variables in the Seto Inland Sea, Japan Texto completo
2015
Nishijima, Wataru | Umehara, Akira | Okuda, Tetsuji | Nakai, Satoshi
A data set of 425 sites investigated by the Ministry of the Environment in 2001–2005 was used to evaluate the current sediment situation and its effect on macrobenthic community structure in the Seto Inland Sea, Japan. Cluster analysis and principle component analysis of sediments using physico-chemical parameters revealed that total organic carbon, mud, sulfide contents, and oxidation–reduction potential were important parameters influencing macrobenthic population size and biodiversity. A total organic carbon of 1mgg−1 interval was highly negatively correlated with two biodiversity indices in the range of 1–20mgg−1. Overall, 42% of total sites were organically enriched with much lower macrobenthic population sizes and biodiversity, while 26% were characterized by sandy sediment with a high population size and high proportion of Arthropoda. Nemertea sp., Glycera sp., Notomastus sp. and Ophiophragmus japonicus were common macrobenthos, while Theora fragilis and Ptychoderidae were typical macrobenthos in organically enriched sediments.
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