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Journal ArticleDOI

Geochemistry of trace metals in a fresh water sediment : Field results and diagenetic modeling

01 Aug 2007-Science of The Total Environment (Elsevier)-Vol. 381, Iss: 1, pp 263-279
TL;DR: Pore water and sediment analyses indicate a shift in trace metal speciation from oxide-bound to sulfide-bound over the upper 20 cm of the sediment, and sensitivity analyses show that increased bioturbation and sulfate availability, expected upon restoration of estuarine conditions in the lake, should increase the sulfide bound fractions of Zn and Ni in the sediments.
About: This article is published in Science of The Total Environment.The article was published on 2007-08-01 and is currently open access. It has received 93 citations till now. The article focuses on the topics: Trace metal & Bioirrigation.

Summary (4 min read)

1. Introduction

  • In freshwater sediments, sulfide mineral phases may also immobilize trace metals, despite the lower sulfate concentrations relative to marine systems (Huerta-Diaz et al., 1998; Motelica-Heino et al., 2003).
  • Others have applied multi-component RTMs to assess metal sulfide oxidation (Carbonaro et al., 2005; Di Toro et al., 1996) and the controls on arsenic mobility in sediments (Smith and Jaffe, 1998).
  • A better understanding of trace metal behavior in sediments is needed to guide management efforts to improve water quality and ecosystem health of the lake.

2. Study site

  • In 1970, the Haringvliet estuary was converted to a freshwater lake by building a dam at the outlet to the North Sea (Fig. 1).
  • A partial restoration of estuarine conditions is proposed for Haringvliet Lake, beginning in 2008.
  • Changes in management of the dam will allow water from the adjacent North Sea to enter the lake at high tide.
  • Trace metal contamination has adversely affected benthic communities in sediments of the Rhine–Meuse Delta where low species diversity has been correlated with sediment toxicity including elevated trace metal Netherlands with a box denoting the location of the detail section.
  • Concentrations (Reinhold-Dudok van Heel and den Besten, 1999).

3.1. Sample collection

  • Sediment and pore water samples were collected in September 2002, and April–May 2003.
  • The sampling periods are referred to as late-summer, and spring, respectively.
  • Sediment was collected using a cylindrical box corer, with a 31 cm inner diameter, deployed from RV Navicula.
  • Subcores were taken with polycarbonate tubes (10 cm i.d.).
  • Sub-cores for pore water and solid phase analysis were taken from a single box core and immediately sectioned in a N2 purged glove box on board the ship.

3.2. Pore water analyses

  • Sediment sub-samples for pore water collection were placed in polyethylene centrifuge tubes in a N2 purged glove box during core sectioning.
  • Sulfide was measured colorimeterically (Cline, 1969) using filtered pore water fixed with NaOH (10 μl 1 M NaOH per ml).
  • The pore water concentration was then derived from the estimated diffusive flux through the gel following the established procedure (e.g. Zhang et al., 1995; Naylor et al., 2004).
  • The probes were inserted into sediment cores and incubated for 24 h in the temperature controlled shipboard laboratory.
  • Following incubation, the agarose gel was removed from each individual compartment and eluted in 1 ml 1MHNO3.

3.3. Solid phase analyses

  • Sediment water content and density were determined from the weight loss upon freeze drying, allowing for the determination of sediment porosity.
  • Total carbon, total sulfur, and organic carbon (Corg; following carbonate removal with 1 M HCl) were determined on freeze-dried sediment using an elemental analyzer (LECO SC-1440H).
  • Analysis ofmetals in all extractants was carried out with ICP-MS unless otherwise noted.
  • It is important to note that AVS includes a range of sulfide containing compounds (Rickard and Morse, 2005).
  • The reactive pool extraction in the HuertaDiaz and Morse (1990) method (1 M HCl) is less specific, as it also mobilizes reactive Fe(II) phases (Kostka and Luther, 1994).

3.4. Modeling

  • Reaction-transport model calculationswere carried out with the Biogeochemical Reaction Network Simulator (BRNS; Aguilera et al., 2005; Jourabchi et al., 2005).
  • The discussion of reaction and transport processes in this paper is limited to those that directly involve the trace metals.
  • The model describes 1-D sediment profiles at steady-state.
  • The ability of thermodynamic modeling to predict the speciation of dissolved metals is limited by the use of pure, end-member solid phases and, the limited knowledge of metal–sulfide stability constants.

4.1. Porewater

  • Pore water DOC displayed a gradual increase with depth in late-summer, while a subsurface maximum was observed in spring (Fig. 2).
  • Pore water analyses based on the DGT method indicated the presences of free sulfide in the upper 10 cm of sediment.
  • The pore water concentrations of Zn, Pb, and Cd were similar for the two sampling times.
  • Pore water profiles of Co and Ni resembled those of Mn, for both sampling periods.

4.2. SPM metal content

  • Trace metals in the water column of the Haringvliet Lake are mainly associated with the SPM.
  • Concentrations of solid-phase Zn, Ni, Pb, and Cd in the upper 2 cm of sediment exhibit the same order of abundance and the same magnitudes as in the lake SPM (Fig. 4).
  • Concentrations of Fe and Mn in the SPM varied independently from one another (Fig. 5), as previously observed at other sites in the Rhine–Meuse Delta (Paalman and van der Weijden, 1992).
  • The SPM trace metal concentrations varied substantially in the period 2000–2004, with coefficients of variation ranging from 17% for Zn to 55% for Cd (see error bars on Fig. 4).
  • The trace metal SPM concentrations displayed negative correlations with SPMorganicmatter content; indicating that organicmatter produced in the lake during algae blooms had a lower trace metal content than the terrestrially derived SPM.

4.3. Sediment solid phase

  • The sediment is highly porous, fined grained and organic rich (Table 1).
  • The total sediment profiles of Corg, Fe, Mn, Zn, Pb, Co, and Cd displayed little variation with depth, particularly in the upper 10 cm of sediment (Fig. 6).
  • As expected, the AVS-SEMconcentrationswere lower than the respective total concentrations (Fig. 6).
  • The concentrations of CDB extractable Fe, Ni, and Co declined more sharply with depth than the ascorbate extractable concentrations.

5.1. Pore water profiles

  • The build up of alkalinity in the pore waters reflects Corg mineralization (Fig. 2).
  • The authors previous work has shown that sulfate reduction is an important mineralization pathway (Canavan et al., 2006), which explains the rapid depletion of pore water SO4 2− and the presence of measurable free sulfide.
  • The pore water profiles of Zn, Pb, and Cd show a near-surface enrichment in spring (Fig. 2).
  • For Zn and Pb, the reductive extraction results imply that the near-surface pore water enrichments can, in part, be explained by reductive dissolution of reactive Fe and Mn oxide phases close to the sediment–water interface.
  • The concentration ratios of Mn to Co and Ni in the pore waters (approximately 2000 and 700, respectively) are much higher than those measured in the reductive extractions (Mn:Co=100–450 and Mn:Ni=50–155).

5.2. Sediment solid phase

  • The correlations of sediment Corg, Al, and Fe concentrations with grain size b63 μm (Table 1) indicate a close association of OM, metal oxides and clay minerals (Tessier et al., 1996).
  • The concentrations of target values for of the Dutch Soil Protection Although pore water profiles suggest diagenetic remobilization may occur in the sediment (Fig. 2), those processes to not result in a redistribution of the total sediment concentration profiles, with the exceptions of S and possibly Ni (Fig. 6).
  • The decreasing concentrations with increasing depth of the ascorbate and CDB extractable Fe pools are consistent with reductive dissolution of Fe(III) in the sediment (Fig. 7).
  • The progressive decrease with depth of the ascorbate and CDB extractable concentrations of Mn, Zn, Ni, and Co also indicate release from reducible mineral phases (Fig. 7).

5.3. Diagenetic modeling

  • The second fractio to both oxide pools 3 Oxide formation Mn2+ and Fe2+ can oxidatively precipita trace metal with the same oxideQtrace m 4 Bioirrigation ZnS concentrations rresponds with that given in Fig. 10 f Fe-oxides (Zn), Mn-oxides (Ni), or FeS2 (Ni) by a ratio derived from eductive dissolution.
  • In a simulation run without ZnS oxidation the flux of dissolved Zn2+ across the SWI changed from an efflux of 24 nmol cm−2 yr−1 to an influx of 9 nmol cm−2 yr−1 into the sediment.
  • Ni is estimated at 833 through model fitting of the pore water Ni2+ profile, also known as The ratio of FeS.
  • The simulated changes to sediment processes resulting from estuarine restoration are shown to have a greater effect on the solid phase speciation than on metal efflux.

6. Conclusions

  • The Haringvliet Lake sediment exhibits elevated concentrations of trace metals (Cd, Co, Ni, Pb, and Zn) derived from riverine suspended particles.
  • Results of extractions show declining concentrations of reducible phases and an increase in sulfide species with depth.
  • Pore waters are supersaturated with respect to Zn, Pb, Co, and Cd monosulfides, while Ni and Co are found to be associated with pyrite.
  • These results illustrate a transition from oxide-bound to sulfide-bound trace metals with depth in the sediment.
  • Total metal sediment profiles suggest that little metal release from the sediment is occurring with the possible exception of Ni. Diagenetic model simulations predict a greater mobility of Ni than Zn, as Ni does not form stable metal-sulfides, and is more slowly removed by oxidative precipitation at the sediment surface.

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Dissertation
19 Jul 2011
TL;DR: Oruro Department is located in the central part of the Sn belt, and despite mining activities having been practiced since the XVIIth century, very little is known about the geochemical characteristics and dispersion processes affecting this area as mentioned in this paper.
Abstract: Oruro is located on the Bolivian Altiplano at 230 km south of La Paz. The main hydrological system in the Altiplano is endorheic and is constituted by Lake Titicaca-Desaguadero River-Lake Poopo-Coipasa Salar (TDPS) sub-basins. This area presents a dry (DS) and a wet season (WS). Despite the existence of a WS, precipitation is scarce, nevertheless, intensity increases interannually associated with ENSO events. Geomorphologically, this area is made up of the Altiplano and the Eastern Cordillera related to epithermal and Cu deposits and the Eastern Cordillera related to numerous metallogenic belts, including the well-known Sn belt. Oruro Department is located in the central part of the Sn belt, and despite mining activities having been practiced since the XVIIth century, very little is known about the geochemical characteristics and dispersion processes affecting this area. The above, motivated the detailed study of lacustrine sedimentary cores in this area. Two coring campaigns (DS and WS) allowed retrieving a total of 5 sedimentary cores, 4 within Lake Uru Uru (2 en the DS y 2 en the WS) and one in Cala Cala Lagoon (18 km E of Oruro), the later to obtain the local geochemical background. Laboratory analysis was performed in the Laboratoire des Mecanismes et Transferts en Geologie (LMTG, Toulouse), where a total of 91 sediment samples and 222 pore water samples (PW) were studied. The geochemical background and metal(loid) sources allowed us to propose that As and Sb are significantly enriched in comparison to the upper continental crust (UCC), world background levels, industrialized areas and historic mining sites. These conclusions allow us to support the use of local enrichment factors (EF) and discard the use of the UCC to calculate EFs. Many potential sources of contaminants make it difficult to discriminate natural from anthropogenic contributions, nevertheless, we propose that anthropogenic impact in superficial soils is related to trace elements dispersion from the Vinto Smelter, while the metal(loid) content within Lake Uru Uru is mainly associated with mining activities. Early diagenesis processes studies, allowed us to determine that metal(loid)s within Cala Cala Lagoon are less available and mobile than within Lake Uru Uru and high trace element concentrations in pore water are explained by the proximity to the metallogenic belts located along the Eastern Cordillera and not by anthropogenic influence. Northern Lake Uru Uru presents the lower mean dissolved trace element concentration and their behavior is highly influenced by seasonal changes. Indeed, as the reductive dissolution of Fe- and-Mn oxyhydroxides takes place, metal(loid)s are released mainly from sediments to the water column. In this area solid state partitioning (SSP) of metal(loid)s shows moderate changes between different seasons. Metal(loid)s in southern Lake Uru Uru area are the most reactive, available and mobile. During the DS, dissolved metal(loid) behavior is associated with evaporation, this was not observed during the WS. The highest dissolved Sb and Mo concentrations are found in this area during both seasons and Cd only in the DS. Solid state partitioning (SSP) changes fractionation greatly during WS so that metal(loid)s can be easily released into the pore water when reducing conditions are achieved, in this area the most unstable elements are Mo, U, Sb, Pb and Cd. This area represents the most important environmental concern, because besides WS, anthropogenic influence associated with the Huanuni Mine exists, probably contributing with dissolved Sb and Mo, and as demonstrated by other study, Mo competition with Cu induces dietary deficiencies in farm animals. We stress that it is in this area where most flora and fauna live and fishing is usually practiced. We recommend to better define metal(loid)s behavior within the WC, especially during WS and cold ENSO (La Nina) events. Regarding mining history and climate in relation to sediment deposition within the Bolivian Altiplano, we determined that during the last century, Sn exploitation and production influenced Sb-Ag-Pb deposition in sediments from Lake Uru Uru. Additionally, ENSO events may play an important role in the precipitation of authigenic mineral during early diagenesis processes. Finally, we propose that the contribution of metal(loid)s deposited in this area is mainly related to three sources: local geology, authigenic minerals formation under WS influence and mainly during cold ENSO events (La Nina) and gangues and ores from mining origin.

7 citations


Cites background from "Geochemistry of trace metals in a f..."

  • ...(2007) [309] (see above), we also propose that the decreasing Asasc and Sbasc contribution with depth (Fig....

    [...]

  • ..., [302, 309, 310, 311, 312]), our knowledge about early diagenesis in freshwater environments is fragmentary....

    [...]

  • ...Additionally, the incomplete Feasc (and Mnasc) consumption with depth indicates slow dissolution kinetics despite the reducing conditions [309]....

    [...]

  • ...As the main contribution of Cd is not associated with the crystalline structure of minerals (but also weakly sorbed onto exchangeable, carbonates and/or OM/sulphides), we suggest that any environmental change might involve variations in Cd behaviour, for instance release in the top of the pro le might be related to OM mineralization as observed in estuarine sediments [302] and freshwater environments [309], or dissolved Cd release might be associated with carbonate dissolution, as observed in the Dead Sea [327]....

    [...]

  • ...With the exception of Cu, Cd and Pb, and as suggested for other freshwater environments [309], the decreasing pro le of Feasc (and lesser Mnasc; Fig....

    [...]

Dissertation
01 Jan 2011
TL;DR: A collection of 91 sediment samples retrieved from ve sedimentary cores from Lake Uru Uru (Altiplano) and Cala Cala Lagoon (Eastern Cordillera) subjected to a total digestion technique, plus a compilation of preexistent data base of trace element concentration in soil and lacustrine sediment obtained from the Oruro Pilot Project (PPO) allowed to propose a geochemical background and a present-time baseline for As, Cd, Cu, Pb, Sb and Zn in sediments from this area as mentioned in this paper.
Abstract: Oruro, located on the Bolivian Altiplano, has been subjected to intense mining and smelting activities since Colonial times (XVIIth century), yet the current geochemical composition of sediments and trace element behaviour is practically unknown. A collection of 91 sediment samples retrieved from ve sedimentary cores from Lake Uru Uru (Altiplano) and Cala Cala Lagoon (Eastern Cordillera) subjected to a total digestion technique, plus a compilation of preexistent data base of trace element concentration in soil and lacustrine sediment obtained from the Oruro Pilot Project (PPO) allowed to propose a geochemical background and a present-time baseline for As, Cd, Cu, Pb, Sb and Zn in sediments from this area. Results obtained by statistics and geographical information system (GIS) analyses showed that the natural geochemical background of As and Sb is signi cantly enhanced in comparison to the Upper Continental Crust (UCC) concentration, world background levels, industrial sites and historical mining sites. The use of a local enrichment factor (EF) normalized by the mean concentrations of Cala Cala Lagoon (CCLAC), demonstrated that using UCC concentrations to calculate EFs (EFUCC) is inadequate for this highly mineralized environment and therefore is not supported. Regarding metals and metalloids, the strong multiplicity of sources in this environment makes it di cult to discriminate between natural and anthropogenic input into this endorheic drainage basin, although it is suggested that super cial soils are probably impacted

7 citations


Cites background from "Geochemistry of trace metals in a f..."

  • ...(2007) [309] (see above), we also propose that the decreasing Asasc and Sbasc contribution with depth (Fig....

    [...]

  • ..., [302, 309, 310, 311, 312]), our knowledge about early diagenesis in freshwater environments is fragmentary....

    [...]

  • ...Additionally, the incomplete Feasc (and Mnasc) consumption with depth indicates slow dissolution kinetics despite the reducing conditions [309]....

    [...]

  • ...As the main contribution of Cd is not associated with the crystalline structure of minerals (but also weakly sorbed onto exchangeable, carbonates and/or OM/sulphides), we suggest that any environmental change might involve variations in Cd behaviour, for instance release in the top of the pro le might be related to OM mineralization as observed in estuarine sediments [302] and freshwater environments [309], or dissolved Cd release might be associated with carbonate dissolution, as observed in the Dead Sea [327]....

    [...]

  • ...With the exception of Cu, Cd and Pb, and as suggested for other freshwater environments [309], the decreasing pro le of Feasc (and lesser Mnasc; Fig....

    [...]

Journal ArticleDOI
TL;DR: In this article, the authors analyzed the elemental concentrations and zinc stable isotope ratios (δ66Zn) in a sediment core from the Northern basin of Lake Biwa and concluded that the increasing trace metal concentrations in the acid-labile and reducible fractions towards the surface indicate these fractions were the primary host for anthropogenic trace metals.

7 citations

Journal Article
TL;DR: In this article, the spatial variability of acid-volatile sulfide (AVS) and its influential factors were studied through regression analysis to explain the spatial distribution of AVS and to predict the variability of metal availability under changing conditions.
Abstract: The spatial variability of acid-volatile sulfide (AVS) and its influential factors were studied through regression analysis to explain the spatial distribution of AVS and to predict the variability of metal availability under changing conditions simply and effectively. The AVS equation is used to derive oxidation-reduction potential (Eh), sulfate-reducing bacteria (SRB), organic carbon (OC), and total sulfur (TS). The relationships of these variables with AVS were then analyzed. Moreover, their effect on AVS was quantified through linear regression (LR) and principal component regression (PCR). These two regression equations were analyzed using a histogram of residual values and by comparing mean relative error (MRE) and root-mean-square error (RMSE) values. LR (Model 1) and PCR (Model 2) models were established as well. The MRE and RMSE values in the PCR model were 21.9 and 25.9%, respectively. In terms of these values, the PCR model is more accurate than the LR model. Furthermore, its predictive results were more reasonable. In conclusion, the PCR model can be used to predict the AVS concentrations based on the OC, Eh, SRB, and TS values. This model simplifies and facilitates the evaluation of metal toxicity under field conditions and can thus be used to manage sediments contaminated with metals.

6 citations


Cites background or methods from "Geochemistry of trace metals in a f..."

  • ...Most of these models are diagenetic and are based on complicated thermodynamic equilibrium calculations that require many parameters (Di Toro et al., 1996; Fang et al., 2002; Van Griethuysena et al., 2005; Canavan et al., 2007; Adeline et al., 2011; Dale et al., 2013; Murphy et al., 2014; Hong et al., 2014)....

    [...]

  • ...…effect of biogeochemical processes on the availability of metals in sediments (Di Toro et al., 1996; Oehm et al., 1997; Fang et al., 2002; Van Griethuysena et al., 2005; Canavan et al., 2007; Adeline et al., 2011; Wadhawan et al., 2013; Dale et al., 2013; Murphy et al., 2014; Hong et al., 2014)....

    [...]

  • ...Given the complexity of this calculation, a related software was developed (Van Griethuysena et al., 2005; Canavan et al., 2007; Adeline et al., 2011)....

    [...]

  • ...Researchers have used various models to explain the effect of biogeochemical processes on the availability of metals in sediments (Di Toro et al., 1996; Oehm et al., 1997; Fang et al., 2002; Van Griethuysena et al., 2005; Canavan et al., 2007; Adeline et al., 2011; Wadhawan et al., 2013; Dale et al., 2013; Murphy et al., 2014; Hong et al., 2014)....

    [...]

  • ...…models are diagenetic and are based on complicated thermodynamic equilibrium calculations that require many parameters (Di Toro et al., 1996; Fang et al., 2002; Van Griethuysena et al., 2005; Canavan et al., 2007; Adeline et al., 2011; Dale et al., 2013; Murphy et al., 2014; Hong et al., 2014)....

    [...]

Journal Article
TL;DR: In this paper, the evolution of the main components of the control in the calcination (Corg, CO2, P2O5, CaO), the specific surface area and density of the ore according to the time and temperature of calcination were studied.
Abstract: The calcination of phosphate consumes the fossil energy and generates greenhouse gas emissions. This later owed not only on the consumption of these energies, but also in the decomposition of carbonates and in the combustion of the organic matter. The energy consumption and the emission of gases require an optimization of the calcination depending on the residence time and temperature of calcination. These walking parameters influence the chemical reactivity and the solubility of finished product. To assist in that, we have studied the evolution of the main components of the control in the calcination (Corg, CO2, P2O5, CaO), the specific surface area and density of the ore according to the time and temperature. This treatment was performed in the laboratory in a fixed bed. The different analytical techniques that were applied are: sieve analysis, quantitative study by ICP, the mineralogical characterization by X-ray and differential thermal analysis coupled with thermogravimetric analysis. The obtained results show that mechanisms relative to the heat treatment of the phosphate are multiple and are strongly influenced by the nature of the matrix and the parameters of the treatment. The obtained product answers well the trade profiles and the requirements for use under the conditions of a temperature approximately of 800

6 citations


Cites background from "Geochemistry of trace metals in a f..."

  • ...On one hand, they are not biodegradable, and secondly, they accumulate in the environment and in particular in sediments by partnering with organic and inorganic materials by the interplay of adsorption phenomena, the complexation and the chemical combinations [19], [20]....

    [...]

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Frequently Asked Questions (1)
Q1. What have the authors contributed in "Geochemistry of trace metals in a fresh water sediment: field results and diagenetic modeling" ?

Canavan et al. this paper measured trace metal concentrations in pore water and sediment of a coastal fresh water lake ( Haringvliet Lake, The Netherlands ).