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Number of results: 9
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Abstract

Codeposition of antimony and tin from acidic chloride and chloride-sulfate baths was investigated. The calculations of distribution of species showed domination of neutral SnCl2 and anionic SbCl4 – complexes in chloride solution, while in the presence of sulfate ions neutral SnSO4 and cationic SbCl2+ complexes were found. Cyclic voltammetry, anodic stripping analysis and potentiostatic measurements showed that antimony deposited favorably and the reaction run under limiting control. Analysis of chronoamperometric curves suggested instantaneous nucleation of the solid phase in the chloride bath, but progressive model was more probable in the presence of sulfate ions.
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Abstract

The study presents the results of the research into different phosphorus forms in the bottom sediments of anthropogenic limnic ecosystems i.e. the reservoirs of Pławniowice, Rybnik and Goczałkowice (SP). The bottom sediments of dam reservoirs were investigated by chemical extraction procedure for phosphorus forms. The lowest value of the mean AAP form percentage in the Pławniowice bottom sediments reflected the effect of reclamation with the hypolimnetic removal that had been conducted in the reservoir since 2003. The highest percentage of the RDP form (2%) was found in the Goczałkowice bottom sediments. The order of the specific speciation forms in the bottom sediments of the examined reservoirs was: Rybnik: AAP > EP > WDP > RDP; 4,630> 3,740 > 117 > 65 > 3.5 mgP/kg Pławniowice: AAP > EP > WDP > RDP; 916 > 783 > 107 > 15 > 1.4 mgP/kg Goczałkowice: AAP > WDP > EP > RDP; 686 > 628 > 51 > 7 > 0.14 mgP/kg The mutual correlations between the phosphorus speciation forms (AAP : EP : WDP : RDP) were as follows: Rybnik: 1,323 : 1,068 : 33 : 18 : 1; Pławniowice: 654 : 559 : 76 : 11 : 1; Goczałkowice: 4,900 : 4,485 : 364 : 50 : 1. The comparison of the mean concentration values for specific phosphorus forms in the bottom sediments of the three investigated reservoirs demonstrated that the Rybnik sediments had the highest contents of phosphorus. The contents in Pławniowice and Goczałkowice were 5-7 times lower
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Abstract

Water and bottom sediment samples collected from a few fish-breeding ponds/reservoirs were subjected to tests. The aim of this paper was to determine the total content of aluminium and its fractions in the samples tested to estimate the potential risk to fish caused by the toxic forms of aluminium. The monomeric inorganic aluminium in waters was determined using the ion exchange and extraction-colorimetric method with oxychinoline according to Barnes's-Driscoll's procedure. The bottoms were fractionated using a three-step sequential extraction procedure and the microwave mineralisation. The total content of aluminium in waters and extracts was determined using the spectrophotometric method with eriochromocyanine R, and comparatively using the ICP OES technique. The results were subjected to statistical analysis. The level of concentration of labile Al in the waters about 26-34 μg/dm3 and content of exchangeable Al 5-34 mg/g range in bottom sediments are possibly hazardous to aquatic organisms.
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Abstract

The research objective was to study temporal and spatial relations between specific phosphorus species as well as to examine total phosphorus content in the bottom sediments of an anthropogenic, hypertrophic limnic ecosystem Rybnik Reservoir, functioning under thermal pollution conditions. The chemical extraction procedure for the speciation of bioavailable phosphorus forms was used. It was found that available algae phosphorus was the most dominant phosphorus species in both sediment layers (83%), while the lower share was readily desorbed phosphorus form (0.1%). The phosphorus species concentrations depended on the organic matter concentration. The differences between phosphorus species contents in the upper (5 cm) and lower (15–20 cm) sediment core layers were low. The biologically active sediment layer extended from the sediment surface to at least 20 cm depth of the sediment core. Distributions of the concentrations within the year and at specific sampling points resulted from the variability observed for particular points and transformation intensity. Furthermore in the following study, the reaction rate constant for the increase and decrease in the concentrations of the phosphorus species in sediments was given. It was indicated that the speed of the phosphorus species transformations was affected by the environment temperature. In the heated water discharge zone (water temp. 17–35°C) the concentrations of selected speciation phosphorus forms increased more than in the dam zone (5–25°C). It was also found that the abundance of the bottom sediments with phosphorus species was related to the oblong and transverse asymmetry of reservoir depth.
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Abstract

The aim of this work was to identify concentration levels of different chemical forms of mercury (TGM, TPM) in the ambient air in selected areas of the Silesian Region, characterized by low and high mercury emission. Based on the obtained data TGM and TPM concentration levels were determined. The project also focused on determination of dry and wet deposition of mercury compounds. Data concerning TGM and TPM flux rates in the ambient air and data on mercury deposition were used to determine a deposition coefficient. The coefficient was calculated as a share of mercury deposition on the land surface (dry and wet) to the amount of this contaminant transported with loads of air in the form of TGM and TPM in a given measurement station. At both monitoring stations the deposition coefficient did not exceed 0.2 %. The idea of calculating the deposition coefficient based on the analysis of TGM and TPM flux rate is a new solution. The proposed deposition coefficient allows to quantify information on a selected contaminant concentration and its potential impact resulting from deposition. Further studies on the deposition coefficient may contribute to the development of methods for estimating the impact of contaminants contained in the ambient air on other environmental components based on the analyses of the contaminant flux rate.
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Abstract

The aim of the study was verification of the response of chamomile (Matricaria recutita (L.) Rauschert), peppermint (Mentha x piperita) lemon balm (Melissa officinalis L.), and sage (Salvia officinalis L.) on the elevated contents of inorganic As species in soils. The ability of herbs to accumulate arsenic was tested in pot experiment in which soils were contaminated by As(III) and As(V). The As(III), As(V), AB (arsenobetaine), MMA (monomethylarsonic acid) and DMA (dimethylarsinic acid) ions were successfully separated in the Hamilton PRP-X100 column with high performance-liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) techniques. The study examined total arsenic contents in soil and plants, as well as the mobility of the arsenic species from the soil into the studied plants. Peppermint demonstrated the highest arsenic concentration and phytoaccumulation among studied plants. The sequential chemical extraction showed that arsenic in the contaminated soil was mainly related to the oxide and organic-sulfide fractions. The results showed that the oxidized arsenic form had a greater ability to accumulate in herbs and was more readily absorbed from the substrate by plants. Research has shown that soil contaminated with As(III) or As(V) has different effects on the arsenic content in plants. The plant responses to strong environmental pollution varied and depended on their type and the arsenic species with which the soil was contaminated. In most cases it resulted in the appearance of the organic arsenic derivatives.
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Abstract

Water mint (Mentha aquatica L.) belongs to the arsenic tolerant plant species suitable for cultivation in Central European climate conditions. Therefore, its possible application for remediation of contaminated soil was investigated in pot and field experiments. Two M. aquatica plants of different origin, i) commercially market-available mint plants, and ii) plants habituated at the arsenic contaminated former mining area in southern Tuscany (Italy) were tested for their arsenic uptake, transformation, and speciation. The total arsenic concentrations in the experimental soils varied from 21 to 1573 mg As kg-1, the mobile fractions did not exceed 2% of total soil arsenic. The mint plants originating from the contaminated area were able to remove ~400 µg of arsenic per pot, whereas the commercial plant removed a significantly lower amount (~300 µg of arsenic per pot). Only arsenite and arsenate, but no organoarsenic compounds were identified in both stems and leaves. Arsenate was the predominant arsenic compound and reached up to 80% regardless of the origin of the mint plants. Although M. aquatica seems to be able to grow in contaminated soils without symptoms of phytotoxicity, its efficiency to remove arsenic from the soil is limited as can be demonstrated by total elimination of As from individual pots not exceeding 0.1%. Moreover, the application of plants originating from the contaminated site did not result in sufficient increase of potential phytoextraction efficiency of M. aquatica. Although not suitable for phytoextraction the M. aquatica plants can be used as vegetation cover of the contaminated soil at the former mining areas
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Abstract

Exploitation of lignite within the area of Muskau Arch, carried out from the mid-nineteenth century, contributed to the transformation of the natural environment and changes in water regime. In the post-mining subsidences pit lakes were formed. The chemical composition of waters is a consequence of the intensive weathering of pyrite (FeS2), which is present in Miocene lignite-bearing rock forming the embankments of the lakes. This process leads to the formation of Acid Mine Drainage (AMD) and finally acidification of lake waters. This paper presents results of the identification of hydrogeochemical processes affecting the chemistry of waters from these reservoirs carried out using the speciation and statistical (cluster and factor) analyses. Cluster analysis allowed to separate from the analyzed group of anthropogenic reservoirs 7 subgroups characterized by a similar chemical composition of waters. The major processes affecting the chemistry of waters were identified and interpreted with help of factor and speciation analysis of two major parameters (iron and sulfur).
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Abstract

Popular statistical techniques, such as Spearman's rank correlation matrix, principal component analysis (PCA) and multiple linear regression analysis were applied to analyze a large set of water quality data of the Rybnik Reservoir generated during semiannual monitoring. Water samples collected at 9 sampling sites located along the main axis of the reservoir were tested for 14 selected parameters: concentrations of co-occurring elements, ions and physicochemical parameters. The aim of this study was to estimate the impact of those parameters on inorganic arsenic occurrence in Rybnik Reservoir water by means of multivariate statistical methods. The spatial distribution of arsenic in Rybnik Power Station reservoir was also included. Inorganic arsenic As(III), As(V) concentrations were determined by hydride generation method (HG-AAS) using SpectrAA 880 spectrophotometer (Varian) coupled with a VGA-77 system for hydride generation and ECT-60 electrothermal furnace. Spearman's rank correlation matrix was used in order to find existing correlations between total inorganic arsenic (AsTot) and other parameters. The results of this analysis suggest that As was positively correlated with PO43-; Fe and TDS. PCA confirmed these observations. Principal component analysis resulted in three PC's explaining 57% of the total variance. Loading values for each component indicate that the processes responsible for As release and distribution in Rybnik Reservoir water were: leaching from bottom sediments together with other elements like Cu, Cd, Cr, Pb, Zn, Ni, Ca (PC1) and co-precipitation with PO43-, Fe and Mn (PC3) regulated by physicochemical properties like T and pH (PC2). Finally, multiple linear regression model has been developed. This model incorporates only 8 (T, pH, PO43-, Fe, Mn, Cr, Cu, TDS) out of initial 14 variables, as the independent predictors of total As contamination level. This study illustrates the usefulness of multivariate statistical techniques for analysis and interpretation of complex environmental data sets.
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