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Biomonitoring of thallium availability in two estuaries of southwest England
2013
Turner, Andrew | Turner, Deborah | Braungardt, Charlotte
Thallium is a highly toxic metal whose biogeochemical behaviour in the marine environment is poorly understood. We measured Tl in sediments, macroalgae (Fucus vesiculosus and Fucus ceranoides) and deposit-feeding invertebrates (Hediste diversicolor, Arenicola marina and Scrobicularia plana) from two estuaries of south west England (Plym and Fal) draining mineralised catchments. In the Plym, and for a given sample type, concentrations of Tl were rather invariant between sample locations and averaged about 500μgkg−1 for sediment, 30μgkg−1 for macroalgae and 10μgkg−1 for the invertebrates. In the Fal, respective concentrations were of a similar order of magnitude but exhibited greater variation between sample locations. Normalisation of Tl concentrations to K, the biogeochemical analogue of Tl+, revealed bioenrichment of about 20 for all organisms in the Plym and bioenrichment ranging from about 3 (H. diversicolor) to 170 (F. ceranoides) in the Fal. Despite the low bioaccumulation of Tl relative to other metals measured concurrently, it is recommended that Tl be more closely monitored and better studied in the estuarine environment.
Show more [+] Less [-]Fractionation, sources and budgets of potential harmful elements in surface sediments of the East China Sea
2013
Yu, Yu | Song, Jinming | Li, Xuegang | Yuan, Huamao | Li, Ning
Total concentrations, chemical fractions by BCR procedure and enrichment factors of nine potential harmful elements (V, Cr, Co, Ni, Cu, Zn, Mo, Cd and Pb) in surface sediments of the East China Sea (ECS) were investigated. Spatial distributions illustrated that PHEs (potential harmful elements) were mainly from the Changjiang River and the Jiangsu coastal current, except Pb which was influenced by atmospheric input. Sediments in the ECS were moderately polluted with Cd, Pb, Zn and Cu according to their enrichment factors (EFs). Distributions of EFs and labile fractions revealed that anthropogenic Cd and Cu were mainly input though the Changjiang, Pb pollutant was delivered from the Changjiang and atmosphere, while Zn was impacted by terrestrial pollution from the Changjiang and the Hangzhou Bay. Budget calculation showed that the Changjiang contributed 82–90% of PHE influxes. Thirty-eight to 77% of PHEs were buried in sediment, mainly along the inner shelf.
Show more [+] Less [-]Multifractal analysis of ground–level ozone concentrations at urban, suburban and rural background monitoring sites in Southwestern Iberian Peninsula
2013
Pavon-Dominguez, Pablo | Jimenez-Hornero, Francisco J. | Gutierrez de Rave, Eduardo
This paper seeks to enhance understanding of the data distribution of ground–level ozone time series by analysing their multifractal spectra. Emphasis is placed on the suitability of the box–counting and moments methods for characterizing scaling properties of ozone concentration, enabling us to describe similarities and differences inferred from the multifractal spectra by analysing various types of monitoring stations (urban, suburban and rural monitoring sites) under identical atmospheric conditions. It is herein demonstrated that that multifractal features are to a considerable extent similar for each type of monitoring station under warm atmospheric conditions and high solar radiation, owing to the fact that these weather characteristics homogenize the scaling behaviour of ozone. On the contrary, location and chemical precursors play a more prominent role under low temperatures and solar radiation, highlighting differences among multifractal features of ozone concentrations in the monitoring sites. At rural stations, the absence of anthropogenic emissions promotes less variability in ozone data and homogenization of multifractal behaviour throughout the year. Furthermore, a data shuffling procedure was performed in order to analyse changes occurring in multifractal spectra as time series are subjected to varying degrees of data position disturbance. Results indicate that multifractal analysis is a useful tool for describing the temporal scaling behaviour of ozone time series at different monitoring sites which refines results that have been traditionally provided by statistical analyses on ozone pollution.
Show more [+] Less [-]Phylogenetic analysis of bacterial community composition in sediment contaminated with multiple heavy metals from the Xiangjiang River in China
2013
Zhu, Jianyu | Zhang, Jingxia | Li, Qian | Han, Tao | Xie, Jianping | Hu, Yuehua | Chai, Liyuan
Understanding the ecology of sediments that are contaminated with heavy metals is critical for bioremediating these sediments, which has become a public concern over the course of the development of modern industry. To investigate the bacterial community composition of sediments that are contaminated with heavy metals in the Xiangjiang River, a total of four sediment samples contaminated with multiple heavy metals were obtained, and a culture-independent molecular analysis, polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP), was performed. The results revealed that heavy metal pollution affected the sediment microbial community diversity, and the greatest species diversity appeared in the moderately polluted sediment X sample. The dominant family in these sediments includes α-Proteobacteria, β-Proteobacteria and Firmicutes. Moreover, α-Proteobacteria was significantly increased with increases in heavy metal. A redundancy analysis (RDA) also confirmed this phenomenon.
Show more [+] Less [-]Temporal changes in carbon and nitrogen stable isotope ratios of macrozoobenthos on an artificial tidal flat facing a hypertrophic canal, inner Tokyo Bay
2013
Kanaya, Gen | Nakamura, Yasuo | Koizumi, Tomoyoshi | Yamada, Katsumasa | Koshikawa, Hiroshi | Kohzu, Ayato | Maki, Hideaki
Temporal changes in benthic food web structure were analyzed in an artificial tidal flat in inner Tokyo Bay, Japan, using carbon and nitrogen stable isotope ratios (δ13C and δ15N). Microphytobenthos were the most important food sources of macrozoobenthos, due to high microphytobenthic biomass on the tidal flat, while phytoplankton in canal water (canal POMPP), terrestrial materials from urban surface runoff (canal POMTM), and marsh plants were less important. Dietary contribution of microphytobenthos was highest in April to June, while decreased towards December owing to the supply of canal POMPP and canal POMTM following red tides and heavy rainfall events in summer to fall. Temporal changes in δ15N (Δδ15N) of consumer corresponded well to the 15N-enrichment in canal POMPP in summer. A meta-analysis showed that the consumer-Δδ15N was considerably larger in inner Tokyo Bay than those in other estuaries, which may be a specific characteristic of benthic food web in highly urbanized estuaries.
Show more [+] Less [-]Distribution and concentrations of petroleum hydrocarbons associated with the BP/Deepwater Horizon Oil Spill, Gulf of Mexico
2013
Sammarco, Paul W. | Kolian, Steve R. | Warby, Richard A.F. | Bouldin, Jennifer L. | Subra, Wilma A. | Porter, Scott A.
We examined the geographic extent of petroleum hydrocarbon contamination in sediment, seawater, biota, and seafood during/after the BP/Deepwater Horizon Oil Spill (April 20–July 15, 2010; 28.736667°N, −88.386944°W). TPH, PAHs, and 12 compound classes were examined, particularly C1-benzo(a)anthracenes/chrysenes, C-2-/C-4-phenanthrenes/anthracenes, and C3-naphthalenes. Sediment TPH, PAHs, and all classes peaked near Pensacola, Florida, and Galveston, Texas. Seawater TPH peaked off Pensacola; all of the above classes peaked off the Mississippi River, Louisiana and Galveston. Biota TPH and PAHs peaked near the Mississippi River; C-3 napthalenes peaked near the spill site. Seafood TPH peaked near the spill site, with PAHs and all classes peaking near Pensacola. We recommend that oil concentrations continued to be monitored in these media well after the spill has ceased to assist in defining re-opening dates for fisheries; closures should be maintained until hydrocarbon levels are deemed within appropriate limits.
Show more [+] Less [-]Mercury profiles in surface sediments from ten bays along the coast of Southern China
2013
Xu, Weihai | Yan, Wen | Huang, Weixia | Chen, Zhong | Wang, Shuhong | Miao, Li | Zhong, Lifeng | Chen, Han
Spatial and temporal variations of mercury (Hg) were investigated from ten representative bays along the coast of Southern China. The total Hg (THg) in surface sediments varied widely with concentrations from 25 to 264ng/g. As a whole, Hg pollution in several bays occupied by busy sea traffic and industrial activities, such as Shantou (ST) Bay and Dapeng (DP) Bay were remarkably more serious than others, which reflected the direct effects of anthropogenic activities around the coastal areas. Hg variations in sediment cores clearly display upcore rising trend which obviously correlates with the trend of economic development and urbanization in the last five decades. No significant correlations were found between Hg and organic matter and particle size, suggesting that the distribution of Hg is not fully controlled by these variables.
Show more [+] Less [-]Concentration profiles of PCB congeners in the blubber and liver of Steller sea lions (Eumetopias jubatus) from the coast of Hokkaido, Japan
2013
Kubo, Keiko | Yamaguchi, Katsuyuki | Mitsuhashi, Masaki | Hattori, Kaoru | Tanaka, Shunitz
The concentrations of PCB congeners in the blubber and liver of male and female Steller sea lions (Eumetopias jubatus; SSLs) collected from the Shakotan Peninsula and the Nemuro Strait, Hokkaido, Japan in 2008 and 2010 were measured by HRGC–HRMS, in order to express the concentration profiles in SSLs at these regions. #153 predominated in both organs, followed by #138, #99 and #118. In males, #28 and #31 were concentrated particularly in the blubber, while #177 and #199 were accumulated specifically in the liver. The differences in these concentration profiles might be expressed by the differences in the organs and their functions. The concentrations of #99, #118, #138, #153, and #180 in the blubber appeared to correspond significantly with the differences between genders. The details of the surveys on PCB congeners in SSLs could clarify the differences in the residue levels of individual congeners for organs and genders.
Show more [+] Less [-]Occurrence, distribution, and bioaccumulation of antibiotics in coastal environment of Dalian, China
2013
Na, Guangshui | Fang, Xiaodan | Cai, Yaqi | Ge, Linke | Zong, Humin | Yuan, Xiutang | Yao, Ziwei | Zhang, Zhifeng
Seawater, sediment, and aquatic organism samples were collected from 20 sampling sites in coastal environment of Dalian in August, 2011. The occurrence, distribution, and bioaccumulation of 20 antibiotics categorizing into three groups, including 14 sulfonamides (SAs), two chloramphenicols (CAPs) and four tetracyclines (TCs), were investigated. The results suggested that tetracyclines were the predominant antibiotics in the seawater (range: 2.11–9.23ngL−1), while sulfonamides were the dominant antibiotics in both sediments (range: 1.42–71.32μgkg−1) and aquatic organisms (range: 2.18–63.87μgkg−1). The sorption coefficient Kd,s values revealed that sulfameter, sulfadiazine, sulfamethoxypyridazine, sulfamonomethoxine, chloramphenicol, and doxycycline presented higher sorption capacities than the other antibiotics. The average BAFs suggested that sulfamethazine, sulfamethiazole, sulfamonomethoxine, and doxycycline were potentially bioaccumulative, while sulfadiazine, sulfameter, sulfamethoxypyridazine, and chloramphenicol were bioaccumulative.
Show more [+] Less [-]Distribution and geochemical speciation of heavy metals in sediments from coastal area suffered rapid urbanization, a case study of Shantou Bay, China
2013
Qiao, Yongmin | Yang, Yang | Gu, Jiguang | Zhao, Jiangang
Eight metals in sediment samples at 15 sites from the Shantou Bay were analyzed with BCR sequential extraction protocol to obtain the metal distribution patterns in the bay. The results showed that the heavy metal pollutions in upper bay were more severe than in middle and down reaches of the bay. Both total and non-residual fractions of metals with a exception of Mn showed a seaward decrease trend. More than 54% of the total concentrations of Cd, Mn and Zn existed in the acid soluble fraction. Ni, Co, Cr and Fe mainly (more than 51%) occurred in the residual fraction. While Pb and Cu dominantly presented in the reducible (50%) and oxidable (33%) fraction respectively. Principal component analysis (PCA) revealed that the heavy metals in the non-residual fractions resulted from largely anthropogenic sources, including river input, city runoff and port discharge. These contributing sources are highlighted by cluster analysis.
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