Particle Size Effects on Concentration of Metals in Lake Erie Bottom Sediments

1984 ◽  
Vol 19 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Alena Mudroch
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Clay Minerals ◽  
Surface Sediment ◽  
Size Effects ◽  
Lake Erie ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Major Elements ◽  
Sediment Samples

Abstract Surface sediment samples obtained at the offshore and nearshore area of Lake Erie were separated into eight different size fractions ranging from <2 µm to 250 µm. The concentration of major elements (Si, Al, Ca, Mg, K, Na, Fe, Mn and P), metals (Zn, Cu, Cr, Ni, V, Co and Pb) and organic matter was determined together with the mineralogical composition and morphology of the particles in each size fraction. The distribution of the metals in the offshore sediment was bimodal with the majority of the metals divided between the 63 to 250 um size fraction which also contained the highest concentration of organic matter (about 20%) and the <4 µm fraction containing up to 60% of clay minerals. However, the metals in the nearshore sediment were associated mainly with the clay minerals.

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 Long term trends in fertility of soils under continuous cultivation and cereal cropping in southern Queensland. III. Distribution and kinetics of soil organic carbon in particle size fractions

Soil Research ◽  
1986 ◽  
Vol 24 (2) ◽  
pp. 293 ◽  
Author(s):  
RC Dalal ◽  
RJ Mayer
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Size Fraction ◽  
Organic C ◽  
Size Fractions ◽  
Particle Size Fractions ◽  
Clay Size Fraction ◽  
Sand Size

Distribution of soil organic carbon in sand-, silt- and clay-size fractions during cultivation for periods ranging from 20 to 70 years was studied in six major soils used for cereal cropping in southern Queensland. Particle-size fractions were obtained by dispersion in water using cation exchange resin, sieving and sedimentation. In the soils' virgin state no single particle-size fraction was found to be consistently enriched as compared to the whole soil in organic C in all six soils, although the largest proportion (48%) of organic C was in the clay-size fraction; silt and sand-size fractions contained remaining organic C in equal amounts. Upon cultivation, the amounts of organic C declined from all particle-size fractions in most soils, although the loss rates differed considerably among different fractions and from the whole soil. The proportion of the sand-size fraction declined rapidly (from 26% to 12% overall), whereas that of the clay-size fraction increased from 48% to 61% overall. The proportion of silt-size organic C was least affected by cultivation in most soils. It was inferred, therefore, that the sand-size organic matter is rapidly lost from soil, through mineralization as well as disintegration into silt-size and clay-size fractions, and that the clay fraction provides protection for the soil organic matter against microbial and enzymic degradation.

scholarly journals Physio-chemical properties and dynamic of the surface sediment in riparian mangroves along the Tien river, Tien Giang province

2019 ◽  
Vol 2 (5) ◽  
pp. 50-58
Author(s):  
Hung Duc Nguyen ◽  
Ngot Van Pham ◽  
Duy Van Nguyen
Keyword(s):  
Electrical Conductivity ◽  
Organic Matter ◽  
Surface Sediment ◽  
Chemical Properties ◽  
Total Sulfur ◽  
Mean Sea Level ◽  
Factors Affecting ◽  
Sediment Samples ◽  
Mesohaline Zone ◽  
Saturated Extract

This study was conducted to investigate the physio-chemical properties and vertical dynamic of the surface sediment (0–5 cm) in riparian mangroves along the Tien river, Tien Giang province. The distribution of riparian mangroves located from the polyhaline zone (transect S1 and S2) to the mesohaline zone (transect S3 and S4) and the oligohaline zone (transect S5). Three plots (10x10 m) per transect were set based on the elevation of the mangrove floor (cm + mean sea level) and dominant plants. A total of 28 sediment samples were collected in December 2016 and April 2017. Seasonal variation of pH, redox potential (Eh), electrical conductivity of saturated extract (ECse), bulk density, sediment organic matter (SOM) and total sulfur (TS) were measured in accordance with the standard protocols. Seasonal trends of vertical erosion and accumulation were tested by the tracer stick method. The ECse values and TS concentrations were higher in the dry season and in transects closed to the estuary (S1, S2 and S3) but these trends weren’t found for pH, Eh, and SOM. In most of the riparian mangroves along the Tiền river, low elevation (0–50 cm) was one of important factors affecting the Eh and ECse. In the rainy season, major changes in vertical erosion and acumulation have occurred in the transects near the mouth of the river.

ÉTUDE COMPARATIVE DE L'AGRÉGATION ET DE LA MATIÈRE ORGANIQUE ASSOCIÉE AUX FRACTIONS GRANULOMÉTRIQUES DE SEPT SOLS SOUS CULTURE DE MAÏS OU EN PRAIRIE

1990 ◽  
Vol 70 (3) ◽  
pp. 395-402 ◽  
Author(s):  
J. ELUSTONDO ◽  
M. R. LAVERDIÈRE ◽  
D. A. ANGERS ◽  
A. N'DAYEGAMIYE
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Size Fraction ◽  
Cropping System ◽  
Clay Content ◽  
Size Fractions ◽  
Particle Size Fractions ◽  
Carbon And Nitrogen ◽  
Water Stable Aggregates ◽  
Continuous Corn

Water-stable aggregation and organic matter associated with particle-size fractions were compared for seven pairs of soils that were either under meadow or continuous corn cropping for more than 5 yr. Soils that have remained under meadow contained 25 and 29% more carbon and nitrogen than those under continuous corn. Carbon contents of the sand- and silt-size fractions were also 61 and 15% higher, respectively, under meadow than under continuous corn. The cropping system had no significant effect on the carbon and nitrogen contents of the clay-size fractions. The amount of water-stable aggregates (> 1 mm) was on average 34% higher in soils under meadow than in soils under corn cropping. Significant correlations were found between water-stable aggregates and total C (r = 0.77) and C in sand-size fraction (r = 0.79). The results also indicate that the beneficial effect of meadow over continuous corn on soil aggregation increases as soil clay content increases. Key words: Aggregation, organic matter, particle-size fractions, corn, meadow

Nitrogen and C/N ratios in the sediments of Lakes Superior, Huron, St. Clair, Erie, and Ontario

1977 ◽  
Vol 14 (10) ◽  
pp. 2402-2413 ◽  
Author(s):  
A. L. W. Kemp ◽  
R. L. Thomas ◽  
H. K. T. Wong ◽  
L. M. Johnston
Keyword(s):  
Organic Matter ◽  
Lake Erie ◽  
Surface Sediments ◽  
Lake Superior ◽  
Lake Ontario ◽  
Lake Huron ◽  
Surface Enrichment ◽  
Large Component ◽  
Sediment Samples ◽  
Modern Sediment

The distribution of nitrogen (N) was determined on 1238 surface sediment samples (0–3 cm) and 24 cores from Lakes Superior, Huron, St. Clair, Erie, and Ontario. The concentration of N was greatest in the depositional basins of the lakes. The N concentrations decreased sharply from high values at the sediment–water interface to uniformly lower N values at the base of the cores. The surface enrichment was related to increased inputs of N to the lakes since settlement of the region in the order: Lake Ontario > Lake Erie [Formula: see text] Lake Superior > Lake Huron > Georgian Bay.The organic carbon: total nitrogen (C/N) ratios averaged 10.2 in the surface sediments with a range of 5.1 to 66.0. The lowest ratios were found in the depositional basins, with the exception of Lake St. Clair. The magnitude of the C/N ratios was related to the source of the organic matter. Plankton, which are the main source of Org-N in the lakes, accounted for C/N ratios between 7 and 9. Dilution of the modern sediment with organic matter from glacial deposits yielded the higher ratios and low Org-C contents in the nondepositional zones. The high C/N ratios and Org-C contents in Lake St. Clair were believed to be due to a large component of macrophytes in the inputs of organic matter to the lake sediments.

Linking the redox cycles of Fe oxides and Fe-rich clay minerals: an example from a palaeosol of the Upper Freshwater Molasse

Clay Minerals ◽  
2008 ◽  
Vol 43 (1) ◽  
pp. 69-82 ◽  
Author(s):  
H. Stanjek ◽  
C. Marchel
Keyword(s):  
Particle Size ◽  
Clay Minerals ◽  
Soil Formation ◽  
Mineralogical Composition ◽  
Rietveld Analysis ◽  
Fe Oxides ◽  
Redox Cycles ◽  
Upper Freshwater Molasse ◽  
Fine Clay ◽  
Dioctahedral Smectite

AbstractA profile within the Upper Freshwater Molasse (OSM) of eastern Switzerland was sampled. Particle-size analyses, bulk chemical analyses, cation exchange capacities and Fe fractions (oxalate- and dithionite-citrate-bicarbonate-soluble Fe, total Fe) were measured. The mineralogical composition was determined by X-ray diffraction and quantified with Rietveld analysis. The layer charge of selected fine-clay samples was determined with the alkylammonium method using chainnc= 12. The profile could be divided into a lower sequence (I) and an upper sequence (II) by a hiatus. Chemical data, particle-size distributions and calcite contents indicated that soil formation was essentially restricted to wetting-drying cycles associated with redox cycles evident from Feo/Fedand Fed/Fetratios. A significant correlation between thed060values of the dioctahedral smectite-illite mixed-layer phases and Feo/Fedwas interpreted as the influence of microbial Fe3+reduction, which affected both the Fe oxides and Fe-rich clay minerals. This is the first evidence that the Fe dynamics of both mineral groups may be linked. The amount of illitization also correlated with Feo/Fed, but only in the upper part of the profile. This indicates that wetting-drying cycles were necessary for the illitization process.

Sorption Kinetics of Non-Ionic Organic Pollutants Onto Suspended Sediments

1991 ◽  
Vol 23 (1-3) ◽  
pp. 447-454 ◽  
Author(s):  
H. M. Liljestrand ◽  
Y. D. Lee
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Experimental Studies ◽  
Size Fraction ◽  
Organic Matter Content ◽  
Suspended Sediments ◽  
Spherical Particles ◽  
Particle Model ◽  
Desorption Kinetics ◽  
Kinetics Of

The results of controlled batch experimental studies of the adsorption and desorption kinetics of dichlorobenzene to 1) size fractionated, washed sediments, 2) aggregate, washed sediment, 3) dissolved/colloidal sediment materials, and 4) bulk sediments,are used to determine the effect of inhomogeneous mixtures on the overall sorption rates. The size-segregated sediments are modeled as spherical particles with a porous outer shell of organic matter for sorption and an inert, inorganic core. The characteristic times of intraparticle diffusive transport are found to vary with particle size by about two orders of magnitude. The distribution of natural organic matter content with particle size results in sorption rates which differ greatly from that predicted by the monodisperse, homogeneous particle model. Coupled, reversible reactions between the solute and each solid size fraction are presented as a conceptual model for the interpretation of the empirical results of batch experiments.

scholarly journals Methods of improvement chalcedonite processing effectiveness with the use of density separation

2017 ◽  
Vol 33 (3) ◽  
pp. 163-178
Author(s):  
Zdzisław Naziemiec ◽  
Paweł Pichniarczyk ◽  
Daniel Saramak
Keyword(s):  
Particle Size ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Industrial Applications ◽  
Density Fractions ◽  
Size Classification ◽  
Dense Media ◽  
Fine Size ◽  
Dense Liquid

Abstract The article regards the issues related to chalcedonite processing by means of particle size classification as well as densimetric separation. Chalcedonite is an unique rock and material with wide industrial applications in various industries. The investigative program included laboratory tests of chalcedonite classification in the classifier and the jig, as well as separation of the material in the dense liquid. The obtained results indicate that the products of particle size classification of chalcedonite in the classifier are characterized by a different chemical and mineralogical composition. The 0-0.3 mm particle size fraction contains over 96% of quartz, while the fine size fraction below 0.063 mm contain about 80% of quartz and 20% of clayish minerals. In the next stage of the investigative program, the densimetric separation of chalcedonite material in the jig and in dense liquid, was carried out. The results of the density classification in the jig indicate the different absorbability of the obtained chalcedonite density fractions. Fractions with a higher density were characterized by lower water absorption. The results of separation in the dense media liquid also showed that the obtained aggregate products are of significant differences in absorbability as well as high variability of the strength parameters. The results of the investigations show that the obtained products of the classification can be more efficiently utilized in industry, due to their diverse chemical and physical characteristics.

Factors Influencing the Robustness and Accuracy of Near Infrared Reflectance Spectroscopy (NIRS) Calibrations for Ps5edicting the Digestibility of Grass Silages

1993 ◽  
Vol 1993 ◽  
pp. 50-50
Author(s):  
C W Baker ◽  
D I Givens
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Size Effects ◽  
Near Infrared ◽  
Reflectance Spectroscopy ◽  
Infrared Reflectance ◽  
Near Infrared Reflectance Spectroscopy ◽  
Near Infrared Reflectance ◽  
Factors Influencing

Earlier studies showed the superiority of NIRS, over fibre measurements, for predicting organic matter digestibility (OMD) in vivo of grass silages. (Barber et al 1990). This system was put into routine use in ADAS in 1989 and after some initial doubts, due to the wider range of the predicted data seen, is now accepted as the best system available for routine use. However, occasional erroneous values were predicted for which there were no obvious explanations, and which resulted in occasional relatively poor repeatability. In common with all NIRS applications it was likely that the sources of the problems contributing to the errors were i) instrumental and environmental noise, ii) sample particle size effects and iii) variable moisture content of the samples. A course of investigation was undertaken with the objective of determining the effects of these on the predicted data.

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