Microbial methylation of mercury in upper Wisconsin river sediments

1986 ◽  
Vol 29 (4) ◽  
Author(s):  
StevenM. Callister ◽  
MichaelR. Winfrey
Keyword(s):  
River Sediments ◽  
Wisconsin River ◽  
Microbial Methylation

Flavor Tainting of Fish in the Upper Wisconsin River Caused by Alkyl- and Thiophenols

1992 ◽  
Vol 25 (2) ◽  
pp. 35-40
Author(s):  
R. C. Lindsay ◽  
T. P. Heil
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Food Chain ◽  
River Sediments ◽  
Gas Chromatography Mass Spectrometry ◽  
Stizostedion Vitreum ◽  
Paper Mills ◽  
Chromatography Mass Spectrometry ◽  
Wisconsin River ◽  
Off Flavors

Compounds responsible for pronounced off-flavors in Walleye pike (Stizostedion vitreum) and other sportfish in the Upper Wisconsin River were identified by gas chromatography-mass spectrometry and sensory techniques. Alkylphenols (2-isopropyl-, 3-isopropyl, 4-isopropyl-, 2,4-diisopropyl-, 2,5-diisopropyl-, 2,6-diisopropyl-, 3,5-diisopropyl-, 5-methyl-2-isopropyl-, and 2-methyl-5-isopropyl-) and thiophenol were found to be the principal contributors to flavor tainting in fish which was most pronounced in the spring. Data indicated that thiophenol entered the river sporadically through discharges from paper mills. Analysis of fish, river sediments, insects, and woods supported a hypothesis that alkylphenols were indirectly derived from paper pulping activities, and that the food chain of fish was involved in the transport of alkylphenols from the environment to fish.

Distribution of Mercury in Lake St. Clair and the St. Clair River Sediments

1989 ◽  
Vol 24 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Alena Mudroch ◽  
K. Hill
Keyword(s):  
Organic Matter ◽  
Sediment Cores ◽  
River Sediments ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Recent Sediment ◽  
Geochemical Composition ◽  
Visual Appearance ◽  
Decaying Wood ◽  
Relationship Of

Abstract Sediment cores were collected in Lake St. Clair in 1985 and in the St. Clair River in 1986 to investigate the horizontal and vertical distribution and association of Hg in the sediments. A layer of recent sediment up to about 35 cm thick was differentiated by the geochemical composition and visual appearance from the underlying glacial-lacustrine deposits. The concentration of Hg in the surficial sediments in Lake St. Clair was lower in 1985 (<0.025 to 1.200 µg/g) than that found in 1974 (<0.20 to 3.00 µg/g). Up to 8.30 µg/g of Hg were found in the sediments collected from the nearshore area at Sarnia, Ontario, in the St. Clair River in 1986. The concentrations of Hg ranged from 5.05 to 16.00 µg/g in different sand-sized fractions (0.063 to 0.350 mm) of the sediment. The concentration of Hg was 17.80 µg/g in the silt-clay size fraction (<0.063 mm). No relationship was found between the concentration of organic matter and Hg, and the concentration of silica and Hg in the St. Clair River sediments. The results indicated a relationship of Hg with particles of different mineralogical composition. Up to 3.72 µg/g Hg was found in the surface sediment in Chenal Ecarte. The greatest concentration of Hg (13.15 µg/g) existed in the 0.350 mm particle size fraction, which consisted mainly of small pieces of decaying wood. A good relationship was found between the concentration of Hg and organic matter in the sediment at this area.

scholarly journals Modeling of dense well block point bar architecture based on geological vector information: A case study of the third member of Quantou Formation in Songliao Basin

2021 ◽  
Vol 13 (1) ◽  
pp. 39-48
Author(s):  
Chao Luo ◽  
Ailin Jia ◽  
Jianlin Guo ◽  
Wei Liu ◽  
Nanxin Yin ◽  
...  
Keyword(s):  
River Sediments ◽  
Three Dimensional ◽  
Songliao Basin ◽  
Point Bar ◽  
Meandering River ◽  
Architecture Model ◽  
The Third ◽  
Continuous Convergence ◽  
Vector Information ◽  
Architecture Modeling

Abstract Although stochastic modeling methods can achieve multiple implementations of sedimentary microfacies model in dense well blocks, it is difficult to realize continuous convergence of well spacing. Taking the small high-sinuosity meandering river sediments of the third member of Quantou Formation in Songliao Basin as an example, a deterministic modeling method based on geological vector information was explored in this article. Quantitative geological characteristics of point bar sediments were analyzed by field outcrops, modern sediments, and dense well block anatomy. The lateral extension distance, length, and spacing parameters of the point bar were used to quantitatively characterize the thickness, dip angle, and frequency of the lateral layer. In addition, the three-dimensional architecture modeling of the point bar was carried out in the study. The established three-dimensional architecture model of well X24-1 had continuous convergence near all wells, which conformed to the geological knowledge of small high-sinuosity meandering river, and verified the reliability of this method in the process of geological modeling in dense well blocks.

Effects of seasonal variation and resuspension on microplastics in river sediments

2021 ◽  
pp. 117403
Author(s):  
Feiyang Xia ◽  
Quanwei Yao ◽  
Jun Zhang ◽  
Dunqiu Wang
Keyword(s):  
Seasonal Variation ◽  
River Sediments

High mobilization of phosphorus in black-odor river sediments with the increase of temperature

2021 ◽  
Vol 775 ◽  
pp. 145595
Author(s):  
Ming Kong ◽  
Tianlun Han ◽  
Musong Chen ◽  
Donghua Zhao ◽  
Jianying Chao ◽  
...  
Keyword(s):  
River Sediments

Modern isotopic signatures of Plata River sediments and changes in sediment supply to the western subtropical South Atlantic during the last 30 kyr

2021 ◽  
Vol 259 ◽  
pp. 106910
Author(s):  
Natalie Höppner ◽  
Cristiano M. Chiessi ◽  
Friedrich Lucassen ◽  
Karina Zavala ◽  
Raúl A. Becchio ◽  
...  
Keyword(s):  
River Sediments ◽  
South Atlantic ◽  
Sediment Supply ◽  
Isotopic Signatures
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