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Spatial variability in community composition on a granite breakwater versus natural rocky shores: Lack of microhabitats suppresses intertidal biodiversity 全文
2014
Aguilera, Moisés A. | Broitman, Bernardo R. | Thiel, Martin
Strong differences have been observed between the assemblages on artificial reefs and on natural hard-bottom habitats worldwide, but little is known about the mechanisms that cause contrasting biodiversity patterns. We examined the influence of spatial attributes in relation to both biogenic and topographic microhabitats, in the distribution and composition of intertidal species on both artificial and natural reefs. We found higher small-scale spatial heterogeneity on the natural reef compared with the study breakwater. Species richness and diversity were associated with a higher availability of crevices, rock pools and mussels in natural habitats. Spatial distribution of certain grazers corresponded well with the spatial structure of microhabitats. In contrast, the lack of microhabitats on the breakwater resulted in the absence of several grazers reflected in lower species richness. Biogenic and topographic microhabitats can have interactive effects providing niche opportunities for multiple species, explaining differences in species diversity between artificial versus natural reefs.
显示更多 [+] 显示较少 [-]Mussel watch update: Long-term trends in selected contaminants from coastal California, 1977–2010 全文
2014
Melwani, Aroon R. | Gregorio, Dominic | Jin, Yujie | Stephenson, Mark | Ichikawa, Gary | Siegel, Emily | Crane, Dave | Lauenstein, G. G. | Davis, Jay A.
This study examined trends in contaminants measured during three decades of “Mussel Watch” monitoring on the California coast. Chlorinated organic contaminants and butyltins declined the most rapidly, with tissue concentrations in 2010 that were up to 75% lower than during the 1980s. Silver and lead declined at about half of the stations statewide, but generally exhibited slower rates of decline relative to the organic compounds. In contrast, copper increased at many stations, and PAHs showed little evidence for declines. Mussels from San Francisco Bay and the Southern California Bight were historically the most contaminated and have had the steepest declines. Overall, these data show that the “Mussel Watch” approach to monitoring contaminants in California has provided some of the best evidence of the effectiveness of actions to improve water quality over the past 30years. These datasets also highlight challenges that remain in managing PAHs and copper.
显示更多 [+] 显示较少 [-]Expansion of an invasive coral species over Abrolhos Bank, Southwestern Atlantic 全文
2014
Costa, Thiago J.F. | Pinheiro, Hudson T. | Teixeira, João Batista | Mazzei, Eric F. | Bueno, Leonardo | Hora, Mike S.C. | Joyeux, Jean-Christophe | Carvalho Filho, Alfredo | Amado-Filho, Gilberto | Sampaio, Claudio L.S. | Rocha, Luiz A.
Invasive coral species of the genus Tubastraea have been increasingly recorded in Southwestern Atlantic waters since the 1980s. Their invasion and infestation are mainly related to port and oil exploration activities. For the first time the presence of Tubastraea tagusensis colonies is reported in Espírito Santo State, colonizing a port shore area, and incrusting oil/gas platform structures situated in the southern Abrolhos Bank, which is part of the most important coral reef system of the South Atlantic Ocean. Tubastraea colonies exhibit fast growth and high recruitment rates, and colonized 40% of the analyzed structures in just four years. The projection of port and oil/gas industry growth for the Espírito Santo State (more than 300%) highlights an alert to the dispersal of this alien species to natural areas.
显示更多 [+] 显示较少 [-]Enhanced methane emissions from oil and gas exploration areas to the atmosphere – The central Bohai Sea 全文
2014
Zhang, Yong | Zhao, Hua-de | Zhai, Wei-dong | Zang, Kun-peng | Wang, Ju-ying
The distributions of dissolved methane in the central Bohai Sea were investigated in November 2011, May 2012, July 2012, and August 2012. Methane concentration in surface seawater, determined using an underway measurement system combined with wavelength-scanned cavity ring-down spectroscopy, showed marked spatiotemporal variations with saturation ratio from 107% to 1193%. The central Bohai Sea was thus a source of atmospheric methane during the survey periods. Several episodic oil and gas spill events increased surface methane concentration by up to 4.7 times and raised the local methane outgassing rate by up to 14.6 times. This study demonstrated a method to detect seafloor CH4 leakages at the sea surface, which may have applicability in many shallow sea areas with oil and gas exploration activities around the world.
显示更多 [+] 显示较少 [-]Disutility analysis of oil spills: Graphs and trends 全文
2014
Ventikos, Nikolaos P. | Sotiropoulos, Foivos S.
This paper reports the results of an analysis of oil spill cost data assembled from a worldwide pollution database that mainly includes data from the International Oil Pollution Compensation Fund. The purpose of the study is to analyze the conditions of marine pollution accidents and the factors that impact the costs of oil spills worldwide. The accidents are classified into categories based on their characteristics, and the cases are compared using charts to show how the costs are affected under all conditions. This study can be used as a helpful reference for developing a detailed statistical model that is capable of reliably and realistically estimating the total costs of oil spills. To illustrate the differences identified by this statistical analysis, the results are compared with the results of previous studies, and the findings are discussed.
显示更多 [+] 显示较少 [-]Effect of glyphosate-based herbicide on early life stages of Java medaka (Oryzias javanicus): A potential tropical test fish 全文
2014
Yusof, Shahrizad | Ismail, Ahmad | Alias, Mohamad Shafiq
Glyphosate is globally a widely used herbicide, yet there is little information on their toxicity to marine fishes. Java medaka, a small tropical fish native to coastal areas in several Southeast Asian countries, is viewed as a suitable candidate for toxicity test and thus was used for this study. Java medaka adults were cultured in the laboratory and the fertilized eggs of the F2 generation were exposed to different concentrations of glyphosate-based herbicide (100, 200, 300, 400 and 500ppm) until they hatched. The survival and hatching rates of the embryos, changes in the heart rate and morphological impairments were recorded. Generally, survival and hatching percentage decreased as glyphosate concentration increased. Absence of pectoral fin(s) and cornea, permanently bent tail, irregular shaped abdomen, and cell disruption in the fin, head and abdomen are among the common teratogenic effects observed. Furthermore, risk factor also increased with the increased in glyphosate concentrations.
显示更多 [+] 显示较少 [-]Evaluation of the suitability of Tillandsia usneoides (L.) L. as biomonitor of airborne elements in an urban area of Italy, Mediterranean basin 全文
2014
Pellegrini, Elisa | Lorenzini, Giacomo | Loppi, Stefano | Nali, Cristina
The suitability of a rootless Bromeliad species (Tillandsia usneoides) as biomonitor of airborne trace elements in urban areas of the Mediterranean basin was evaluated. The study was performed at five sites of the city of Pisa (Tuscany, Central Italy) differing for land use, anthropogenic activities and/or proximity to emission sources. The elements investigated were Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, V and Zn. Unwashed and washed samples, collected after 36 days of exposure (May–June 2011), were analyzed by ICP–MS. Results showed significant differences among sampling sites for several elements. Concentrations of Al, Ba, Bi, Cd, Co, Cu, Pb, Sb and Zn were the highest in urban/traffic and/or suburban/traffic areas. Some of these elements e.g. Ba, Cu, Sb and Zn are commonly considered as traffic–related elements. In the industrial site, the main elements found were Mg, Sr and Zn. Iron, Mn, Na and V concentrations were much higher in rural/remote areas. Enrichment factors highlighted that T. usneoides showed: high resistance/tolerance to heavy metal toxicity, specificity, capability to well–definitely represent a sampling site, quantitative response to pollutant exposure. The results indicated that T. usneoides reflects the intrinsic characteristics of each sampling area and allows tracing back differences related to the various emission sources by factor analysis.
显示更多 [+] 显示较少 [-]Benzo[a]pyrene modulates the biotransformation, DNA damage and cortisol level of red sea bream challenged with lipopolysaccharide 全文
2014
Bo, Jun | Gopalakrishnan, Singaram | Chen, Fang-Yi | Wang, Ke-Jian
In animals, biotransformation and the immune system interact with each other, however, knowledge of the toxic mechanism of benzo[a]pyrene (BaP) on these two systems is not well known. The present study investigated the toxic effects of BaP on the biotransformation system, cortisol level and DNA integrity of red sea bream (Pagrus major). The results showed that cortisol level was induced under the challenge of lipopolysaccharide (LPS). Short-term exposure (96h) of BaP at environmental concentration significantly increased the cortisol level, hepatic EROD activity and CYP1A1 mRNA expression. When P. major was exposed to BaP for 14 d followed by LPS challenge this increased the cortisol level, EROD activity and hepatic DNA damage except CYP1A1 mRNA expression. Combined with our previous data, which showed that BaP exposure can modulate the immunologic response in P. major challenged with LPS, a hypothetical adverse outcome pathway of BaP on fish was suggested.
显示更多 [+] 显示较少 [-]Conservation management options and actions: Putative decline of coral cover at Palmyra Atoll, Northern Line Islands, as a case study 全文
2014
Gardner, Jonathan P.A. | John Bartz, R. | Brainard, Russell E. | Collen, John D. | Dunbar, Robert B. | Garton, David W. | Powell, Sam
Localised loss of live coral cover at Palmyra Atoll (central Pacific Ocean) has been attributed to increased temperature and/or sedimentation arising from alterations made to the lagoon system. It has been hypothesised that a causeway spanning the lagoon hinders water circulation, resulting in warmer and/or more turbid water flowing towards a site of high coral cover and diversity (Coral Gardens). Analyses of a multi-site and multi-year data set revealed no differences in mean temperature or turbidity values on either side of the causeway and provided no evidence of significantly warmer or more turbid water at Coral Gardens. We conclude that the putative decline in live coral cover cannot be attributed to the presence of the causeway and that proposed management actions involving modification to the causeway cannot achieve the conservation outcomes suggested of them.
显示更多 [+] 显示较少 [-]Polychlorinated biphenyl (PCB) concentrations and congener composition in masu salmon from Japan: A study of all 209 PCB congeners by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) 全文
2014
Matsumoto, Reiko | Tu, Nguyen Phuc Cam | Haruta, Shinsuke | Kawano, Masahide | Takeuchi, Ichirō
We collected two subspecies of masu salmon: Oncorhynchus masou masou from four localities (southern Sea of Japan northward to Hokkaido) and O. masou ishikawae from upstream from Ise Bay close to a heavy industrial area. All 209 PCB congeners were analyzed using HRGC/HRMS. PCA ordination of congener concentrations divided data into three groups: (i) ssp. masou from Hokkaido, (ii) ssp. masou from the other regions and (iii) ssp. ishikawae. The highest ∑ PCB concentration (40.39ng/wet wt) was in ssp. ishikawae followed by ssp. masou from southern waters; however the TEQdioxin-like PCBs was highest in ssp. masou from southern water (1.96pg-TEQdioxin-like PCBs/g wet wt.) due to the high proportion of congener #126 in its complement (#126 has the highest toxic equivalency factor among congeners). There is likely a contamination source offshore in the southern Sea of Japan and/or along the migratory route of ssp. masou.
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