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Geographic and temporal patterns of variation in total mercury concentrations in blood of harlequin ducks and blue mussels from Alaska Full text
2017
Savoy, Lucas | Flint, Paul | Zwiefelhofer, Denny | Brant, Heather | Perkins, Christopher | Taylor, Robert | Lane, Oksana | Hall, Jeff | Evers, David | Schamber, Jason
We compared total mercury (Hg) concentrations in whole blood of harlequin ducks (Histrionicus histrionicus) sampled within and among two geographically distinct locations and across three years in southwest Alaska. Blue mussels were collected to assess correlation between Hg concentrations in locally available forage and birds. Mercury concentrations in harlequin duck blood were significantly higher at Unalaska Island (0.31±0.19 mean±SD, μg/g blood) than Kodiak Island (0.04±0.02 mean±SD, μg/g blood). We found no evidence for annual variation in blood Hg concentration between years at Unalaska Island. However, blood Hg concentration did vary among specific sampling locations (i.e., bays) at Unalaska Island. Findings from this study demonstrate harlequin ducks are exposed to environmental sources of Hg, and whole blood Hg concentrations are associated with their local food source.
Show more [+] Less [-]Characteristics of mass concentration, chemical composition, source apportionment of PM2.5 and PM10 and health risk assessment in the emerging megacity in China Full text
2017
Jiang, Nan | Yin, Shasha | Guo, Yue | Li, Jingyi | Kang, Panru | Zhang, Ruiqin | Tang, Xiaoyan
In this study, 228 daily Particulate matter (PM) filters (57 Quartz and 57 Teflon samples for both PM2.5 and PM10, respectively) were collected from an urban site in Zhengzhou in typical months from 2014 autumn to 2015 summer representing the four seasons. PM concentrations, water-soluble inorganic ions, organic carbon, elemental carbon, and elements were determined, and positive matrix factorization was used for source apportionments. Health risks of toxic elements in PM2.5 and PM10 were also evaluated. The annual mean values of PM2.5 and PM10 were higher than the standards in China, and the highest seasonal concentrations of PM2.5 and PM10 were in winter. Secondary inorganic aerosols (SIAs) were the major component, with the ratio of SIAs/PM highest in summer. The seasonal concentrations of SO42− were high in winter and summer. Crustal elements mainly existed in PM2.5–10; however, elements from anthropogenic sources (i.e., Zn, Pb, Cu, As, Cd, and Mo) were more abundant in fine particles than in the coarse fraction. The main pollution sources were dust, SIAs, coal combustion, vehicle and road dust, and industry, accounting for 10%, 26%, 25%, 20% and 15% in PM2.5 and 32%, 14%, 24%, 18% and 8% in PM10, respectively. Dust source has the highest contribution in PM10; however, SIAs source has the highest content in fine particles. The carcinogenic risks of As to children through the daily intake pathway in PM2.5 and PM10 exceeded the acceptable level. Noncarcinogenic risks of As and Cd in PM2.5 and PM10 to children via the daily intake pathway were significant. Moreover, the sum of noncarcinogenic risks in PM10 via inhalation exposure for local residents and that via dermal absorption for children were significant. The details of the pollution characteristics and the results of source apportionments and health risks assessment of PM2.5 and PM10 in this study can play an important role for the government to formulate reasonable and effective policy to mitigate the atmospheric pollution of PM. To our knowledge, this systematic study is the first to investigate the chemical characterizations, source apportionments, and health effects of PM2.5 and PM10 in Zhengzhou.
Show more [+] Less [-]An investigation of the space distribution of Ulva microscopic propagules and ship-based experiment of mitigation using modified clay Full text
2017
Li, Jing | Song, Xiuxian | Zhang, Yue | Pan, Jun | Yu, Zhiming
Previous studies suggested that the removal of Ulva microscopic propagules (UMP) from cradle water might restrict the formation and expansion of green tides in the Yellow Sea, China. In this study, the distribution characteristics of UMP in the southern Yellow Sea was investigated, and then a flocculation experiment of UMP using modified clay (MC) was conducted at a selected station of the research cruise. The results indicated that the distribution of green algae thalli is one of the main factors that directly influence UMP distribution. UMP density was strongly negatively correlated with the distance between the sampling station and the centre of the area containing floating Ulva (r=−0.618***, n=83). >80% of the UMP was removed from the water column after MC application at a concentration of 0.1g/L, and MC applied at a concentration of 0.5g/L reduced the germination rate to 0.3%.
Show more [+] Less [-]Compositional shifts in bacterial communities associated with the coral Palythoa caribaeorum due to anthropogenic effects Full text
2017
Paulino, Gustavo Vasconcelos Bastos | Broetto, Leonardo | Pylro, Victor Satler | Landell, Melissa Fontes
Corals harbor abundant and diverse prokaryotic communities that may be strongly influenced by human activities, which in turn compromise the normal functioning of coral species and predispose them to opportunistic infections. In this study, we investigated the effect of sewage dumping on the bacterial communities associated with the soft coral Palythoa caribaeorum at two sites in the Brazilian coast. We observed a dominance of bacterial species classified as human pathogens at sites exposed to untreated sewage discharge. The microbial diversity of undisturbed sites was more homogeneous and diverse and showed greater abundance. In addition, bacterial communities differed substantially between the exposed and undisturbed areas. The microbial community associated with the samples collected from the exposed sites revealed the anthropogenic effect caused by organic matter from untreated sewage dumping, with an abundance of pathogenic bacterial species.
Show more [+] Less [-]Population dynamics of the rock shell Reishia clavigera associated with different degrees of organotin contamination in Hong Kong Full text
2017
Ho, Kevin K.Y. | Leung, Kenneth M.Y.
Application of organotins in antifouling systems on ship hulls has been globally prohibited by the International Maritime Organization since September 2008. It is, therefore, anticipated that there is a recovery of imposex-affected gastropod populations worldwide. We studied the population dynamics of the rock shell Reishia clavigera in six locations around Hong Kong's coastal waters, covering different degrees of organotin contamination for 25months (2011−2013). Abundance and density of R. clavigera were higher in clean sites, while they tended to grow faster in polluted sites. Over time, we observed recruitments in clean sites while recruitments in polluted sites were limited. The results suggested that the lack of apparent recovery of the local R. clavigera populations was probably due to the prevalence of organotin contamination, especially triphenyltin, in this region. This study, therefore, calls for mitigation and long-term monitoring of organotin contamination in marine environments of Hong Kong and South China.
Show more [+] Less [-]Linking fish species traits to environmental conditions in the Jakarta Bay-Pulau Seribu coral reef system Full text
2017
Cleary, Daniel F.R.
Coral reefs around the globe have been subjected to a wide range of stressors. In the present study, fish species were recorded across a pronounced in-to-offshore gradient in the Jakarta Bay-Pulau Seribu reef system. In addition to this, fish species traits were obtained from FishBase. RLQ analysis revealed a significant association between fish species traits and environmental variables. Fish species associated with perturbed, inshore waters were resilient to disturbance, had higher mortality rates, higher growth rates and mainly consumed animals. In contrast, fish species associated with less perturbed, mid- and offshore waters had greater life expectancy, higher age at maturity, greater life span, greater generation time and mainly fed on plants or plants and animals. Eutrophication, pollution and physical destruction of coral substrate in inshore waters has thus selected for a low biomass and depauperate fish community characterised by fast growing and short lived species.
Show more [+] Less [-]Concentrations of metallic elements in kidney, liver, and lung tissue of Indo-Pacific bottlenose dolphin Tursiops aduncus from coastal waters of Zanzibar, Tanzania Full text
2017
Mapunda, Edgar C. | Othman, Othman C. | Akwilapo, Leonard D. | Bouwman, Hindrik | Mwevura, Haji
Concentrations of metallic elements in kidney, liver and lung tissues of Indo-Pacific bottlenose dolphins Tursiops aduncus from coastal waters of Zanzibar were determined using inductively coupled plasma – optical emission spectroscopy. Cadmium, chromium, copper, and zinc were quantifiable in all tissues at concentration ranges of 0.10–150, 0.08–3.2, 1.1–88 and 14–210μg/g dry mass, respectively. Copper and zinc was significantly higher in liver, and females had significantly higher Cd in liver, and chromium in lung. Generally, T. aduncus dolphins from coastal waters around Zanzibar carry low concentrations of metals compared with dolphins from other areas. Cadmium increased significantly with age in kidney and lung. Copper decreased significantly with age in liver, probably due to foetal metallothionein. This study supplied baseline data against which future trends in marine mammals in the Indian Ocean, the world's third largest, can be assessed.
Show more [+] Less [-]Enrichment, isolation, and biodegradation potential of long-branched chain alkylphenol degrading non-ligninolytic fungi from wastewater Full text
2017
Rajendran, Ranjith Kumar | Lin, Chu-Ching | Huang, Shir-Ly | Kirschner, Roland
4-t-Octylphenol (4-t-OP) has become a serious environmental concern due to the endocrine disruption in animals and humans. The biodegradation of 4-t-OP by pure cultures has been extensively investigated only in bacteria and wood-decaying fungi. In this study weisolated and identified 14 filamentous fungal strains from wastewater samples in Taiwan using 4-t-OP as a sole carbon and energy source. The isolates were identified based on sequences from different DNA regions. Of 14 fungal isolates, 10 strains grew effectively on solid medium with a wide variety of endocrine disrupting chemicals as the sole carbon andenergy source. As revealed by high-performance liquid chromatography analysis, the most effective 4-t-OP degradation (>70%) in liquid medium was observed in Fusarium falciforme after 15days. To our knowledge, this is the first report on the degradation of 4-t-OP as a sole carbon and energy source by non-ligninolytic fungi.
Show more [+] Less [-]Bacterial community structure in the intertidal biofilm along the Yangtze Estuary, China Full text
2017
Guo, Xing-pan | Niu, Zuo-shun | Lu, Da-pei | Feng, Jing-nan | Chen, Yu-ru | Tou, Fei-yun | Liu, Min | Yang, Yi
In this study, the 16S rRNA-based Illumina MiSeq sequencing was used to investigate the bacterial community structure and composition of intertidal biofilm taken along the Yangtze Estuary. The results showed that 680,721 valid sequences of seven samples were assigned to 147,239 operational taxonomic units, which belonged to 49 phyla, 246 family and 314 genera. Compared to other studies on water and sediments in the study area, biofilms showed highest index of bacterial diversity and abundances. At different taxonomic levels, both dominant taxa and their abundances varied among the seven samples, with Proteobacteria as the dominant phylum in general. Principal component analysis and cluster analysis revealed that bacterial communities at WSK differed from those at other sampling sites. Salinity, dissolved oxygen, pH and nutrients were the vital environmental factors to influence the bacterial community structure of biofilms. These results may provide a new insight into the microbial ecology in estuarine environments.
Show more [+] Less [-]Nowhere safe? Exploring the influence of urbanization across mainland and insular seashores in continental Portugal and the Azorean Archipelago Full text
2017
Bertocci, Iacopo | Arenas, Francisco | Cacabelos, Eva | Martins, Gustavo M. | Seabra, Maria I. | Álvaro, Nuno V. | Fernandes, Joana N. | Gaião, Raquel | Mamede, Nuno | Mulas, Martina | Neto, Ana I.
Differences in the structure and functioning of intensively urbanized vs. less human-affected systems are reported, but such evidence is available for a much larger extent in terrestrial than in marine systems. We examined the hypotheses that (i) urbanization was associated to different patterns of variation of intertidal assemblages between urban and extra-urban environments; (ii) such patterns were consistent across mainland and insular systems, spatial scales from 10scm to 100skm, and a three months period. Several trends emerged: (i) a more homogeneous distribution of most algal groups in the urban compared to the extra-urban condition and the opposite pattern of most invertebrates; (ii) smaller/larger variances of most organisms where these were, respectively, less/more abundant; (iii) largest variability of most response variables at small scale; (iv) no facilitation of invasive species by urbanization and larger cover of canopy-forming algae in the insular extra-urban condition. Present findings confirm the acknowledged notion that future management strategies will require to include representative assemblages and their relevant scales of variation associated to urbanization gradients on both the mainland and the islands.
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