Mercury depth profiles in river and marine sediments measured by the diffusive gradients in thin films technique with two different specific resins

Diviš, Pavel; Leermakers, Martine; Dočekalová, Hana; Gao, Yue

doi:10.1007/s00216-005-3360-8

Cited by 50 publications

(24 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…42). In a recent study, depth profiles of reactive mercury species were determined in North Sea sediment, and it was found that peak values are reached at the sediment water interface (43). Hence, genes that confer resistance to toxic mercury ions may be much more important for bacteria dwelling in the surface sediment than for bacteria indigenous to the water column.…”

Section: Formation Of Aggregates and Polysaccharide Productionmentioning

confidence: 99%

Characterization of a marine gammaproteobacterium capable of aerobic anoxygenic photosynthesis

Fuchs

Spring

Teeling

et al. 2007

Proc. Natl. Acad. Sci. U.S.A.

124

119

View full text Add to dashboard Cite

Members of the gammaproteobacterial clade NOR5/OM60 regularly form an abundant part, up to 11%, of the bacterioplankton community in coastal systems during the summer months. Here, we report the nearly complete genome sequence of one cultured representative, Congregibacter litoralis strain KT71, isolated from North Sea surface water. Unexpectedly, a complete photosynthesis superoperon, including genes for accessory pigments, was discov- from a surface water sample taken near the North Sea island Helgoland, by direct plating on complex low-nutrient media. Phylogenetic analysis showed that KT71 was the first cultured representative of a cosmopolitan gammaproteobacterial lineage, which we in the following refer to as the NOR5/OM60 clade (Fig. 1). The first indication for this clade dates back to 1997, when Rappe et al. retrieved two 16S rRNA clones, OM60 and OM241, from the continental shelf off Cape Hatteras, NC (2). In the following years, many sequences have been retrieved that were related to the clone OM60 (e.g.,. By the end of 2005, Ͼ180 partial and full length 16S rRNA sequences available within the public databases were related to KT71 and OM60.KT71 is a Gram-negative, pleomorphic, strictly aerobic, and motile bacterium. It is of an average size of 2 ϫ 0.5 m, has a generation time of 4.5 h, and often grows in flocs. Based on this conspicuous trait and the site of isolation, the name Congregibacter litoralis has been proposed. A full taxonomic description of strain KT71 is currently ongoing (B.M.F., S.S., and R.A., unpublished work). Several more strains belonging to the NOR5/ OM60 clade were isolated off the coast of Oregon, in sterilized seawater, using a high-throughput dilution-to-extinction technique (9, 10). Meanwhile, representatives of the NOR5/OM60 clade were also isolated from Arctic sea ice (11) and coastal sediments (12,13).FISH with rRNA-targeted oligonucleotide probes for NOR5/ OM60 confirmed this clade as an abundant component of the bacterioplankton community in the North Sea around the island Helgoland (1). By the end of July 1998, up to 8% of the total bacterioplankton community comprised members of the NOR5/ OM60 clade (1). A second peak of NOR5/OM60 cells was visible in mid-June (6%). However, NOR5/OM60 was not detected by FISH during the winter months, October to March, suggesting a marked seasonality. The fraction of DNA-synthesizing NOR5/ OM60 cells seems to be quite variable. Active DNA synthesis could be detected in August but not in May 2002, even though NOR5/OM60 was present in high numbers in both samples (6% and 11% of total bacterioplankton cell, respectively) (14).In 2004, KT71 was selected for whole-genome sequencing as part of the Gordon and Betty Moore Foundation (GBMF) Marine Microbiology Initiative. Here, we present data derived from the analysis of the genome of strain KT71 and from ecophysiological experiments addressing some of the predictions derived from genome annotation. Results and Discussion Structure and Phylogenetic Analysis of the Photosynthesis (PS)Operon. The...

show abstract

Section: Formation Of Aggregates and Polysaccharide Productionmentioning

confidence: 99%

Characterization of a marine gammaproteobacterium capable of aerobic anoxygenic photosynthesis

Fuchs

Spring

Teeling

et al. 2007

Proc. Natl. Acad. Sci. U.S.A.

124

119

View full text Add to dashboard Cite

show abstract

“…Hintelmann et al (2002) found that newly deposited Hg is more easily lost through volatilization, suggesting a shallow surface emissions phenomenon. Divis et al (2005) have suggested that Hg emissions from marine and river sediment may be limited to the upper 0 to 4 cm because their data showed large spikes in total and labile Hg in the surface Fe and Mn reduction zone. However, understanding emissions of Hg from varying depths of soils requires further investigation.…”

mentioning

confidence: 99%

An Investigation of the Kinetic Processes Influencing Mercury Emissions from Sand and Soil Samples of Varying Thickness

Quiñones

Carpi

2011

J of Env Quality

View full text Add to dashboard Cite

Mercury fl ux from HgCl 2 -treated sand and untreated soil samples of varying thickness (0.5-15 mm) were measured in dark and light under a Tefl on dynamic fl ux chamber. Mean emissions over a 5.5-d sampling period showed an increase with depth for sand samples between 0.5 and 2 mm, but increasing depth above 2 mm had no eff ect. First-order kinetic models showed strong goodness of fi t to the data and explained a high degree of variability in the emissions profi le of all sand samples (R 2 = 0.70-0.98). Soil samples showed an initial emissions peak that was not correlated with depth, suggesting a very shallow process at work. However, longer-term "baseline" emissions, measured as mean emissions between Days 4.5 and 5.5, did show a relationship with depth. First-order kinetic models showed good fi t for soil samples up to 4 mm thick (R 2 = 0.66-0.91); however, thicker samples did not show a consistent fi t to fi rst-or second-order kinetic models (1° R 2 = 0.00-0.46; 2° R 2 = 0.00-0.54). Th e data suggest that mercury emissions from soil samples may follow a multicomponent model for which more than one component is aff ected by incident radiation.

show abstract

“…Samples were analyzed using cold-vapor atomic fluorescence spectroscopy (CVAFS). Three acid solutions were used to test for Hg(II) elution from resin gels: 0.3 M BrCl solution, aqua regia [HNO 3 : HCl (1:3, v/v)], and a mixed acid solution [HNO 3 : H 2 SO 4 (7:3, v/v)]. Inorganic Hg-spiked (5.0 nM) gels were treated in triplicate, and Hg(II) levels in blank samples were also recorded for each acid.…”

Section: Batch Sorption and Elution Testmentioning

confidence: 99%

Application of diffusive gradients in thin films and core centrifugation methods to determine inorganic mercury and monomethylmercury profiles in sediment porewater

Noh

Hong

Han

2015

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

A diffusive gradient in thin films (DGT) is an in situ sampling technique for the quantitative analysis of contaminant concentrations that is based on the diffusion and adsorption of contaminants on to resin gels. In the present study, a DGT technique was applied to measure total mercury (Hg) and monomethylmercury (MMHg) concentrations in lake and coastal sediment porewaters and compare them with those from ex situ sediment centrifugation. To calculate the total Hg and MMHg concentrations in porewater using the DGT method, the diffusion coefficients of Hg species in a diffusive gel medium was first determined, and then total Hg and MMHg depth profiles were measured using the experimentally determined diffusion coefficients. Using the diffusion coefficients for artificial lake and estuarine waters containing inorganic salts, rather than those for lake and estuarine waters containing Suwannee River humic acid (∼5 mg C L(-1) ), the DGT method demonstrated similar Hg and MMHg profiles to those using the centrifugation method. Based on the need for fine vertical resolution and high metal concentrations to be collected, DGT is suggested to be a reliable method for determining Hg(II) and MMHg depth profiles in sediment porewater.

show abstract

Mercury depth profiles in river and marine sediments measured by the diffusive gradients in thin films technique with two different specific resins

Cited by 50 publications

References 23 publications

Characterization of a marine gammaproteobacterium capable of aerobic anoxygenic photosynthesis

Characterization of a marine gammaproteobacterium capable of aerobic anoxygenic photosynthesis

An Investigation of the Kinetic Processes Influencing Mercury Emissions from Sand and Soil Samples of Varying Thickness

Application of diffusive gradients in thin films and core centrifugation methods to determine inorganic mercury and monomethylmercury profiles in sediment porewater

Contact Info

Product

Resources

About