Metals In Bottom Sediments Research Articles

Distribution of heavy metals in bottom sediments of floodplain lakes and their parent river - a case study of the Słupia

Concentration of trace elements in bottom sediments can be a result of natural accumulation or caused by anthropogenic factors. The content of heavy metals (Cd, Cr, Cu, Ni, Mn, Pb and Zn) in bottom sediments of oxbow lakes and river-bed of the S³upia River at S³upsk was determined. Sediment samples were taken from two oxbow lakes: naturally disconnected and artificially re-connected with the river. The research showed variation in the content of the elements in sediments in relation to the accumulative and erosive activity of the river. At the water inflow into the re-connected oxbow lake, the transporting strength of the river decreased, which favoured the accumulation of heavy metals. The content of heavy metals in bottom sediments taken from the re-connected floodplain lake at the outlet was several-fold lower than at the inlet, for example there was 11-fold less Mn, 9-fold less Cu 9-fold, 3-fold less As and half the amount of Cd, Cr and Ni. The content of heavy metals at the outlet was similar to the one found in sediments of the oxbow lake separated from the river.

Speciation of Heavy Metals in Bottom Sediments of Karra River, Nepal

The chemical forms of copper and zinc have been determined using the fractional scheme of Tessier et al. (1979) in the bed sediments of Karra River, Hetauda, Nepal. The sequential extraction revealed that high percentage of metals was associated in the residual fraction (upstream and downstream). However, in most of the sites in the industrial belt, a significant proportion of metal was associated with the non-residual fraction (64% in Cu and 45% in Zn) which can be remobilized and released to the environment by various physical-chemical processes. This indicates influence of anthropogenic activities on the Karra River

Analysis of labile form of aluminum and heavy metals in bottom sediments from Kongsfjord, Isfjord, Hornsund fjords

The paper presents study results obtained for the bottom sediment samples of fjords Kongsfjord, Isfjord, Hornsund in the form of surface samples and their core profiles. The concentrations of labile form of aluminum and heavy metals were determined using the single-stage extraction with 3 mol L−1 HCl. The obtained results allowed defining the occurrence of variability of labile aluminum form in the samples of bottom sediments of the studied fjords depending on the point and depth of sample collection. The conducted chemometric analysis allowed for the study of spatial variability of aluminum occurrence in the area of the investigated fjords. Based on the analysis, the correlations between aluminum and heavy metals were determined.

Contamination and risk assessment of heavy metals in bottom sediments from Lake Valencia, Venezuela

The contamination and risk assessment of heavy metals in the bottom sediments of the Lake Valencia, Venezuela, was performed by determining the Enrichment Factor (EF), the Geoaccumulation Factor (Igeo), the availability of metals and the Risk Index Code (RAC). The sediments were anthropogenic ally enriched with Pb, Zn, Cu and Cr and classified as uncontaminated to moderately contaminated, with a medium risk of Zn, Co, Ni and Cr, and low risk of Cu, Pb and Cd. Analysis of correlations and PCA showed temporal variations in the concentration of metals in the sediments during the rainy season, and spatial variations, where the depth and anthropogenic inputs are the main variables. The contamination of sediments was located on the axis connecting the mouths of the river Guayos, which crosses the city of Valencia, and the river Guey which crosses the city of Maracay, both highly industrialized. Although the concentration of dissolved heavy metals into the waters was within the regulations, important concentrations of Pb and Hg and the bioaccumulation of Hg and Cr, determined by the Bioconcentration Factor (BCF), were found in the fish tissues which indicate that the metal enrichment of the lake sediments is affecting the biota.

Mobility and toxicity of heavy metals in bottom sediments of Rybnik reservoir

Heavy metals are one of the most important factors among many others in biosphere pollution. Mobility and toxicity of metals associated with bottom sediments are generally affected by metal speciation and sediments compositions. The aims of this study were to investigated the distribution of metal speciation in sediment collected from Rybnik dam reservoir and to asses their toxicity for aquatic ecosystem. The speciation analysis of metal was performed using the three-step method of sequential fractionation by means of the modified BCR technique. Toxicity assestement of the bottom sediment samples was preformed using tests: Phytotoxkit TM , Ostarcodotoxkit F TM , Microtox ® . According to the above results, the mobilization potential of heavy metals in sediments in a decreasing order (fraction I+II): Zn > Cd > Ni > Pb > Cu > Cr. According to the Risk Assessment Code (RAC), the sediments having at low risk (Pb, Cu, Cr), medium risk (Cd, Ni) and high risk (Zn). The analysis of all sediment samples collected from the suited reservoir showed that Classes III (acute hazard 50% ≤ PE < 100%) was represented by 80% samples.

Migration and Forms of Metals in Bottom Sediments of Czerniakowskie Lake

The goal of the research was to determine the concentration of Zn, Cu, Pb and Cd forms in the bottom sediments of Czerniakowskie Lake situated within the boundaries of Warsaw. Sediment cores collected for examination purposes were divided into sections, which were approximately 5 cm thick and were analysed to determine the content of metal forms. In the investigated sediments metals were characterized by different percentage in the individual fractions. Speciation analysis indicated that the following fractions were dominant in the bottom sediments of Czerniakowskie Lake: the fraction connected with iron and manganese oxides (for lead and zinc), the fraction connected with organic matter (for copper), the carbonate fraction and the fraction connected with iron and manganese oxides (for cadmium).

Statistical Analysis of Heavy Metals in Bottom Sediments from the Tuo River in Suzhou City, China and its Implications for Source Identification

Heavy metal (Zn, V, Cr, Co, Cu and Pb) concentrations in bottom sediments from Tuo River in Suzhou City have been analyzed for determing their average levels and distribution concentrations, and statistical analysis (correlation, cluster and principle component) have been taken place for evaluating their lithogenic and/or anthropogenic sources. The results imply that the concentration of metals following the order Co&gt;Zn&gt;V&gt;Cr&gt;Cu&gt;Pb with homogeneous distribution. The lithogenic metals (V, Cr and Co) are enriched out of the city, whereas the anthropogenic (industry and vehicle related) metals (Zn, V, Cu and Pb) are enriched in the city.

Long-range effect of cyanide on mercury methylation in a gold mining area in southern Ecuador

Small-scale gold mining in Portovelo–Zaruma, Southern Equador, performed by mercury amalgamation and cyanidation, yields 9–10 t of gold/annum, resulting in annual releases of around 0.65 t of inorganic mercury and 6000 t of sodium cyanide in the local river system. The release of sediments, cyanide, mercury, and other metals present in the ore such as lead, manganese and arsenic significantly reduces biodiversity downstream the processing plants and enriches metals in bottom sediments and biota. However, methylmercury concentrations in sediments downstream the mining area were recently found to be one order of magnitude lower than upstream or in small tributaries. In this study we investigated cyanide, bacterial activity in water and sediment and mercury methylation potentials in sediments along the Puyango river watershed, measured respectively by in-situ spectrophotometry and incubation with 3H-leucine and 203Hg 2+. Free cyanide was undetectable (< 1 μg·L − 1 ) upstream mining activities, reached 280 μg·L − 1 a few km downstream the processing plants area and was still detectable about 100 km downstream. At stations with detectable free cyanide in unfiltered water, 50% of it was dissolved and 50% associated to suspended particles. Bacterial activity and mercury methylation in sediment showed a similar spatial pattern, inverse to the one found for free cyanide in water, i.e. with significant values in pristine upstream sampling points (respectively 6.4 to 22 μgC·mg wet weight − 1 ·h − 1 and 1.2 to 19% of total 203Hg·g dry weight − 1 ·day − 1 ) and undetectable downstream the processing plants, returning to upstream values only in the most distant downstream stations. The data suggest that free cyanide oxidation was slower than would be expected from the high water turbulence, resulting in a long-range inhibition of bacterial activity and hence mercury methylation. The important mercury fluxes resultant from mining activities raise concerns about its biomethylation in coastal areas where many mangrove areas have been converted to shrimp farming.

Thermodynamic simulation of the effect of eutrophication on the behavior of heavy metals in bottom sediments by the example of the Inan’kovsky water reservoir

A thermodynamic model of the behavior of heavy metals in bottom sediments during their eutrophication is developed. The results show that liberation of heavy metals from the reduced ferrous sorbent is accompanied by sorption on clay and organic sorbents. The process is complicated by competitive correlations between heavy metals and calcium ions, while the formation of carbonate cement in the sediments yields additional sorption. As a result, the predicted concentrations of the majority of microelements, namely heavy metals, in the interstitial water of the reduced bottom sediments do not exceed the maximum permissible concentration (MPC).

Specific features of the distribution of heavy metals in bottom sediments in the Northeast part of the Black Sea

We study the distribution of Fe, Mn, Co, Ni, Cu, Zn, Cd, Hg, Ag, and Au in present-day and ancient bottom sediments in the shelf, slope, and deep-trench areas of the northeast part of the Black Sea. The samples were taken in 1990 in the Crimean, Kerch-Taman, and Caucasian regions. The revealed character of the fields of concentration of metals does not allow one to establish exact regularities in the distribution of Mn, Co, and Cu with Fe. It is shown that the values of the ratios of concentrations of metals increase in the following direction: Au/Cu → Zn/Cu → Co/Fe → Ni/Fe → Mn/Fe → Hg/Cu → Ag/Cu → Cu/Fe. The data on Ag are presented for the first time.

Vertical distributions of heavy metals in bottom sediment in Xi-xi national wetland.

A special sampler was made to drill out long and integrated sediment samples from Xi-xi national wetland of Zhejiang Province,and the contents of Cu,Pb and Zn in the sediments at different depths were tested to evaluate pollution degree of the heavy metals,as well as to determine their distribution along depth in the wetland using the method of geoaccumulation index.The tests and evaluation results showed that the sediments were moderately polluted within 0.6 m below the river bed,and not polluted at the depth deeper than 0.6 m.The concentration of heavy metals in the shallow sediments was found to be higher than that in pore water,which was in turn much more than that in the above water.Heavy metals in pore water of sediments could be released into the above water due to the concentration gradient,indicating that the water quality in the wetland could not be completely recovered only by replacing the polluted water with clean water,but needed to dredge the contaminated sediments in the wetland.The top 0.6 m sediment should be dredged from an economic point of view.

Temporal changes and depth wise variations in pit pond hydrochemistry contaminated with industrial effluents with special emphasis on metal distribution in water–sediment system

The investigation showed pronounced temporal and vertical variations of pit lake-water chemistry contaminated with industrial effluents. An intermixing layer of few meters at a depth of 5–8 m usually separates an upper oxic epilimnion with alkaline pH from deeper sub-oxic/anoxic zone with relatively lower pH. Metal concentrations were in higher magnitude at anoxic zone in comparison to surface layer. Most of the parameters including metals showed higher concentrations during summer, while least concentrations were observed during monsoon. In shallow sediments, metals were mainly in insoluble-residual form, while redox metals were fractionated as oxihydroxide-reducible form. Geoaccumulation of metals in bottom sediments were Fe > Cr > Pb > Cu > Cd > Mn > Zn. Toxicity assessment showed that pit pond water is highly contaminated ( C d = 7.52) and moderate pollution load (PLI = 2.272) in shallow sediments, with metal evaluation index (HEI) value of 11.08 and 15.91 respectively.

Concentrations of heavy metals in bottom sediments of Lake Dautkul as an indicator of anthropogenic impact in the area south of the Aral Sea

Data on the microelement composition of bottom sediment and water samples from Lake Dautkul for recent years are presented. Concentrations of more than 30 chemical elements are determined using instrumental neutron-activation analysis. This allowed the authors to reveal the regularities in the distribution and accumulation of chemical elements in water and bottom sediments. It is shown that bottom sediments exhibit a cumulative effect and prolonged activity, which adversely affect the aquatic medium and can serve an indicator of anthropogenic impact on the area under consideration.

Nature of suspended particulate matter and concentrations of heavy metals in sediment in the southern part of Lake Victoria, East Africa

The concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations and to establish their sources. Metal concentrations were higher in sediment in locations within urban catchments. There were significant differences between sites for concentrations of Cu, Cr, Zn, Hg and Pb in sediment. Mercury concentration was higher in Nungwe Bay sediment compared to other areas, and Cr was higher in Magu Bay, while Cu, Pb and Zn were higher in Mwanza Gulf. Watershed characteristics such as urbanisation, and lake characteristics such as algal biomass, influence the nature of SPM, and hence the concentration of metals in the sediment. The potential to distinguish between different origins of metals in the lake, if the sources of SPM are well construed, is demonstrated.

Approaches to the identification of the origin of heavy metals in bottom sediments and standardization problems: Case study of two SDPP reservoirs in ural region

Concentrations of seven metals in bottom sediments of water-cooling reservoirs of Yuzh- noural'skaya and Troitskaya SDPPs, as well as of less polluted Verkhneural'skoe Reservoir (Chelyabinsk prov- ince) are studied. Small samples taken during one season were used as an example to consider three variants of data analysis: comparison with regional control, search for pair correlations between metals, and multidimen- sional approach. The usefulness of factor analysis for revealing the sources of metals supply to water bodies is demonstrated. The origin of three identified groups of metals is considered from the viewpoint of SDPP oper- ation (for Fe and Pb), correlation with organic matter (for Cu, Zn, Mn), and washing out from nickel-bearing components of soil (for Ni and Co). The problem of choice of monitoring indicators corresponding to the objec- tive of the study is discussed.

Concentrations of selected heavy metals in Ligula intestinalis L., 1758 plerocercoids (Cestoda) compared to it host’s (Tinca tinca L., 1758) organs from Beyşehir Lake (Turkey)

Abstract The accumulation of heavy metals (Cu, Fe, Zn and Mn) was measured by atomic absorption spectrophotometry in some organs of tench (Tinca tinca L., 1758) and tissues of its parasite collected from Beyşehir Lake, and compared with the data from sediments and water. The Cu levels in L. intestinalis L., 1758 plerocercoids were 1.69 times, respectively, higher than those in fish gill. Zn level in L. intestinalis plerocercoids was 2.13 times higher than those in fish liver, was 5.53 times higher than that of the muscle and 3.33 times higher than that in the gill. Significant negative (for Mn) correlation was found between the quantity of heavy metals in water and tissues of L. intestinalis plerocercoids while there was significant negative (for Cu) correlation between the quantity the heavy metals in bottom sediment and tissues of L. intestinalis plerocercoids. This study supports the idea that cestodes aren’t very useful to determine the heavy metal pollution in aquatic system when they are located in their intermediate host’s body cavity.

Concentrations of Cd, Pb, Zn, and Cu in Roach, Rutilus Rutilis (L.) from the Lower Reaches of the Oder River, and Their Correlation with Concentrations of Heavy Metals in Bottom Sediments Collected in the Same Area

The aim of this research was to investigate the type of relationships between the concentrations of heavy metals in bottom sediments and in selected roach, Rutilus rutilus (L.), organs. The material studied included kidney, liver, gill, and muscle tissues of roach caught in selected areas of the Oder River. The contents of Cd, Pb, Zn, and Cu were analyzed in fish organs. The content of heavy metals in roach organs differed depending on the organ or, in some cases, on the feeding site. The concentration of heavy metals in bottom sediments also depended on the site of their collection. Positive mutual correlations between concentrations of selected metals in fish and bottom sediments were found. The contamination of bottom sediments in the lower reaches of the Oder River with Cd, Pb, Zn, and Cu was diverse and depended on the sampling area. The accumulation of metals in the organs of the studied fish varied and was positively correlated with the concentration of metals in sediments.

Fluxes of As, Cu, Hg, Pb in lake sediments in the Coppermine River basin, Canada

Many watersheds in northern Canada are experiencing increasing pressures from resource extraction, development and the long-range transport of atmospheric pollutants. This study examines sediment accumulation and the spatial and temporal distribution of trace metals in bottom sediment of down gradient lakes in the headwaters of the Coppermine River basin, Canada. Sediment cores were collected from Lac de Gras, Desteffany Lake, Point Lake and Daring Lake using a plastic lined K–B single-gravity corer. Each core was dated using 210Pb and concentrations of trace metals (As, Cu, Hg, Pb) were determined in core sections. Sedimentation rates ranged from 101 g m−2 yr−1 at Desteffany Lake to 156 g m−2 yr−1 at Daring Lake and are comparable to other northern lakes. Concentrations of As and Cu were significantly higher at Lac de Gras. Metal loading data and enrichment ratios show that concentrations of Pb and Hg are elevated compared to historic background levels. Metal enrichment is from anthropogenic activities and atmospheric inputs. Lake sediment represents a good indicator of state for the Coppermine basin and documents historic trends of metal deposition. However, the indicator has low sensitivity to change and coarse temporal resolution due to low sedimentation rates in northern environments.

Speciation of some heavy metals in bottom sediments of the Ob and Yenisei estuarine zones

The speciation of Fe, Mn, Zn, Cu, Co, Ni, Cr, Pb, and Cd was studied in 52 samples of bottom sediments collected during Cruise 49 of the R/V Dmitrii Mendeleev in estuaries of the Ob and Yenisei rivers in the southwestern Kara Sea. Immediately after sampling, the samples were subjected to on-board consecutive extraction to separate metal species according to their modes of occurrence in the sediments: (1) adsorbed, (2) amorphous Fe-Mn hydroxides and related metals, (3) organic + sulfide, and (4) residual, or lithogenic. The atomic absorption spectroscopy of the extracts was carried out at a stationary laboratory. The distribution of Fe, Zn, Cu, Co, Ni, Cr, Pb, and Cd species is characterized by the predominance of lithogenic or geochemically inert modes (70–95% of the bulk content), in which the metals are bound in terrigenous and clastic mineral particles and organic detritus. About half of the total Mn amount and 15–30% Zn and Cu is contained in geochemically mobile modes. The spatiotemporal variations in the proportions of metal species in the surface layer of sediments along the nearly meridional sections and through the vertical sections of bottom sediments cores testify that Mn and, to a lesser extent, Cu are the most sensitive to changes in the sedimentation environment. The role of their geochemically mobile species notably increases under reducing conditions.

Comparative study on the accumulation of heavy metals in different organs of tench (Tinca tinca L. 1758) and plerocercoids of its endoparasite Ligula intestinalis

Concentrations of heavy metals (Cu, Fe, Zn, Mn, Cr, Pb and Cd) in some organs of tench and tissues of its parasite found in Kovada Lake (Turkey) were analyzed using atomic absorption spectrophotometry and subsequently compared with the data from sediments and water. Only Cu, Fe, Zn and Mn were detected in water, sediment, plerocercoids of Ligula intestinalis and fish samples, while levels of Cr, Pb and Cd were below the detection limits. Four elements were found at higher concentrations in the plerocercoid than in different fish tissues (muscle, liver and gill), being 1.6-37.4 times higher than that measured in muscle, liver and gill. Significant positive (for Cu) and negative (for Fe, Zn and Mn) correlations were found between the quantity of heavy metals in water and tissues of L. intestinalis plerocercoids while there were significant positive (for Cu and Zn) and negative (for Fe and Mn) correlations between the quantity of heavy metals in bottom sediment and tissues of L. intestinalis plerocercoids. Cestodes were found suitable to reflect the amount heavy metals in sediments, providing more reliable information about the actual pollution of the reservoirs.