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1.
J Environ Sci Health B ; : 1-14, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38853697

ABSTRACT

Selected wild-growing edible fungi (Boletus edulis, Neoboletus luridiformis, Cantharellus cibarius, Macrolepiota procera, Amanita rubescens, Russula virescens, Lycoperdon perlatum, and Flammulina velutipes) along with the poisonous medicinal species Amanita muscaria were collected from five sites in the Bohemian Forest, the Czech Republic and analyzed regarding the contents of 19 elements (Ag, Al, As, Be, Ca, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb, Rb, Se, Tl, and Zn) in their fruiting bodies. The contents of the elements as well as bioconcentration factors (ratios of the element content in dry matter of the mushroom to the content in the soil; BCF) were significantly species dependent. In general, the analysis revealed the most intensive accumulation of Cd, Rb, Ag, Cu, Se, and Zn in the studied mushrooms. B. edulis accumulated Ag, Se, Cd, Rb, Cu, and Zn with average BCF of 31, 25, 18, 13, 3.9, and 2.6, respectively. On the other hand, A. rubescens accumulated Cd, Rb, Ag, Cu, Zn, and As (BCF of 41, 27, 4.8, 3.3, 2.1, and 1.4). The data concerning the detrimental elements in sporocarps of edible mushrooms indicate no negative effect on human health if the fungi are consumed occasionally or as a delicacy.

2.
Int J Med Mushrooms ; 25(8): 43-53, 2023.
Article in English | MEDLINE | ID: mdl-37560889

ABSTRACT

Pleurotus ostreatus was cultivated on a commercially available wheat straw substrate enriched with Zn and Se. Various amounts of Zn (10, 50, and 100 mg) and Se (1, 5, and 10 mg) in suitable forms ((CH3COO)2Zn·2H2O, Zn(NO3)2·6H2O, and Na2SeO3·5H2O, respectively) were dissolved in 50 ml of deionized water and homogenously nebulized into the substrate block of 2.4 kg weight. The increase in the Zn content in fruiting bodies cultivated on the enriched substrate was relatively low compared with fruiting bodies cultivated on the substrate with no addition at the first flush. The application of different Zn compounds (acetate vs. nitrate) gave similar results. However, the addition of 1 mg of Se into the cultivation substrate block increased the content of Se in fruiting bodies to about 3-6 mg/kg dry matter. This content was one order of magnitude higher compared with the Se content in fruiting bodies harvested from the substrate with no Se addition (< 0.12-0.58 mg/kg dry matter). In the case of the addition of 5 mg of Se, there was a further significant increase in the content of this element to about 40-60 mg/kg dry matter.


Subject(s)
Pleurotus , Selenium , Selenium/analysis , Pleurotus/chemistry , Zinc/analysis , Fruiting Bodies, Fungal/chemistry , Triticum
3.
Int J Med Mushrooms ; 24(5): 85-95, 2022.
Article in English | MEDLINE | ID: mdl-35695591

ABSTRACT

In this study, selected detrimental and essential elements were determined in fruiting bodies of Auricularia auricula-judae, Tylopilus felleus, and Pleurotus ostreatus medicinal mushrooms. A. auricula-judae and T. felleus were collected from sampling sites situated in South Bohemia, the Czech Republic, while P. ostreatus samples were obtained after cultivation under defined conditions on a straw substrate block. The elements were determined in underlying soils for T. felleus and bioconcentration factors were calculated. The analysis revealed that T. felleus accumulated Rb, Cd, Cu, Zn, Se, and Mg, with bioconcentration factors of 65.7, 2.47, 2.32, 1.93, 1.67, and 1.27, respectively. The analysis also revealed high contents (expressed as medians) of Ca (1600 mg/kg) and Mg (2040 mg/kg) in A. auricula-judae. On the other hand, the contents of detrimental elements such as Pb (0.10 mg/kg), Cd (0.33 mg/kg), and As (0.10 mg/kg) were lower. In cultivated P. ostreatus, lower element contents for Pb (< 0.05 mg/kg), Al (3.92 mg/kg), Ca (53.6 mg/kg), Mn (3.22 mg/kg), Ni (0.11 mg/kg), and Sr (0.93 mg/kg) were determined compared to both wild-growing A. auricula-judae and T. felleus. No negative effect on human health is expected for the mushroom species studied due to the accumulation of detrimental microelements.


Subject(s)
Agaricales , Pleurotus , Agaricales/chemistry , Auricularia , Basidiomycota , Cadmium , Humans , Lead
4.
J Environ Sci Health B ; 57(4): 243-251, 2022.
Article in English | MEDLINE | ID: mdl-35240938

ABSTRACT

Edible medicinal wild-growing fungi Coprinus comatus, Flammulina velutipes, and Armillaria ostoyae were analyzed with regard to the contents of 21 elements in their fruiting bodies. The samples were collected from selected sites in South Bohemia, the Czech Republic. C. comatus concentrated Ag, Cd, Cu, Se, and Rb with bioconcentration factors of 12, 2.5, 2.3, 1.8, and 1.1, respectively. High contents (all values expressed in mg kg-1 dry matter) of Al (260), Ca (480), Cu (61), Fe (340), Mg (1400), and Zn (86) were determined for this species. F. velutipes was characterized with markedly high contents of Ca (360), Fe (110), Mg (1200), Mn (26), and Zn (98), respectively. A considerably high content of Ag (5.6) was revealed for A. ostoyae. High contents of Ca (150), Cu (28), Fe (190), Mg (1100), Mn (30), and Zn (40) were determined in fruiting bodies of this species as well. The data concerning the detrimental elements in fruiting bodies of studied fungi indicate no considerably negative effect on human health if they are consumed as a delicacy or used in alternative medicine.


Subject(s)
Agaricales , Flammulina , Trace Elements , Armillaria , Coprinus , Fruiting Bodies, Fungal , Humans
5.
Environ Sci Pollut Res Int ; 28(47): 67852-67862, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34268685

ABSTRACT

Four macrofungi species with ecological relationship to birch (Betula sp.) were analyzed with regard to the content of 21 detrimental and essential elements in their fruiting bodies. Two of the species (Leccinum scabrum and Leccinum versipelle) were mycorrhizal forming edible fruiting bodies while the others (Fomitopsis betulina and Inonotus obliquus) parasitic used in alternative medicine. The samples were collected near the town of Vimperk in the Bohemian Forest, the Czech Republic. L. scabrum accumulated Ag, Rb, Cd, Cs, Se, Cu, and Zn with bioconcentration factors of 22, 5.5, 4.7, 3.2, 2.0, 1.7, and 1.4, respectively. Similar trend in bioconcentration was revealed for L. versipelle with bioconcentration factors of 28, 5.2, 2.4, 1.9, 1.6, and 1.6 determined for Ag, Rb, Cu, Se, Zn, and Cd, respectively. Considerably high contents of Ca (400 ± 190 mg kg-1 dry matter), Fe (110 ± 30), Mg (1100 ± 300), and Zn (220 ± 90) were found in F. betulina. Similarly, high contents of Ca (1000 ± 700 mg kg-1 dry matter), Fe (110 ± 30), Mg (2000 ± 1100), Mn (410 ± 270), Rb (160 ± 60), and Zn (140 ± 70) were determined for I. obliquus. The different lifestyles (mycorrhizal vs. parasitic) were reflected in 13 significant differences of element contents.


Subject(s)
Agaricales , Trace Elements , Betula , Czech Republic , Forests , Fruiting Bodies, Fungal/chemistry , Poland , Trace Elements/analysis
6.
J Environ Sci Health B ; 55(4): 319-328, 2020.
Article in English | MEDLINE | ID: mdl-31793393

ABSTRACT

The content of Al, As, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Li, Mg, Mn, Ni, Rb, Se, Sr, and Zn in fruiting bodies of edible mushrooms Calocybe gambosa, Entoloma clypeatum, Entoloma saepium, Xerocomellus chrysenteron, and Amanita rubescens growing in an orchard planted with fruit trees and situated close to a high-grown forest was studied during years 2016-2018. A. rubescens showed the highest potential of the element accumulation with bioconcentration factors of 48.5, 16.2, 7.80, 6.53, 1.75, and 1.68 obtained for Rb, Cd, Cu, Zn, Sr, and Mg, respectively. Both Entoloma species accumulated the elements similarly with bioconcentration factors >1.0 obtained for Rb, Cu, Cd, and Mg. Bioconcentration factors <0.05 were obtained for Al, Cr, Fe, and Pb in all studied species. The contents of beryllium (<0.1 mg/kg dry matter) were always the lowest among the studied elements. The contents of some elements of studied mushroom species significantly fluctuated over the years. Despite the fact that some studied elements (As, Be, Cd, Pb, Ni) are considerably toxic for humans, the pronounced effect on health is not expected if the studied mushroom species are consumed occasionally and do not represent the main component of the diet.


Subject(s)
Basidiomycota/chemistry , Metals/analysis , Agaricales/chemistry , Czech Republic , Environmental Monitoring , Food Contamination/analysis , Trace Elements/analysis
7.
Article in English | MEDLINE | ID: mdl-30663931

ABSTRACT

The fate of Cd, Pb, Cu, Zn, Ni, Cr, and As in a horizontal subsurface flow-constructed wetland was studied. The concentrations of the risk elements in treated municipal wastewater, wetland sediments, and Phragmites australis biomass were determined. Most of the studied elements were removed from the wastewater with fair efficiencies. On the other hand, As was released to treated water in the wetland bed. The removal efficiencies obtained for the individual elements were as follows: 64.2, 48.7, 70.0, 93.9, 63.6, 63.8, and -236.2%, respectively. The concentrations measured in sediments were the highest for samples taken 1 m from the inflow zone. They were 4.11, 2.01, 6.01, 4.85, 3.39, 9.30, and 3.17 times higher as compared to the samples taken in the distance of 10 m. The pollutants were preferentially deposited at the front part of the wetland bed where anaerobic conditions predominated and sulfate reduction took place. There were no significant differences in the concentrations of the studied elements in the aboveground biomass (Phragmites australis) samples taken in the distances of 1, 5, and 10 m from the inflow zone. However, the concentrations measured in the belowground biomass samples were significantly higher for samples taken at the front part of the wetland bed. The individual element concentration ratios between the below- and aboveground biomass measured for samples taken 1 m from the inflow zone were 4.97, 5.97, 2.21, 1.58, 2.26, 5.70, and 2.66 for Cd, Pb, Cu, Zn, Ni, Cr, and As, respectively.


Subject(s)
Arsenic , Metals, Heavy , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/pharmacokinetics , Wetlands , Arsenic/analysis , Arsenic/pharmacokinetics , Biodegradation, Environmental , Biomass , Built Environment , Environmental Monitoring , Follow-Up Studies , Geologic Sediments/chemistry , Humans , Metals, Heavy/analysis , Metals, Heavy/pharmacokinetics , Poaceae/physiology , Seasons , Wastewater/chemistry , Water Purification/methods
8.
Chem Biodivers ; 16(2): e1800478, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30517766

ABSTRACT

Risk and essential elements were determined in fruiting bodies of wild growing edible mushrooms Chlorophyllum rhacodes, Suillus grevillei, Imleria badia, and Xerocomellus chrysenteron collected in an unpolluted site in South Bohemia, the Czech Republic. The elements were also determined in underlying soils and the bioconcentration factors were calculated. The analyses revealed that C. rhacodes accumulated Ag, Cu, Rb, Se, Zn, As, Cd, and Tl. On the other hand, S. grevillei accumulated Cd, Rb, Ag, Se, and Cs. I. badia and X. chrysenteron strongly accumulated Rb, Cs, and Ag; these species showed the ability to accumulate Cu and Zn as well. Contents of detrimental CrVI were in all cases below the quantification limit (0.003 mg kg-1 dry matter). Studied mushroom species (mainly C. rhacodes) accumulated some toxic elements. However, no considerable effect on human health is expected since they are usually consumed as a delicacy and do not represent a major component of diet.


Subject(s)
Agaricales/chemistry , Trace Elements/analysis , Czech Republic , Fruiting Bodies, Fungal/chemistry , Plants, Edible/chemistry , Risk Assessment , Trace Elements/metabolism
9.
Clin Interv Aging ; 12: 2003-2007, 2017.
Article in English | MEDLINE | ID: mdl-29225462

ABSTRACT

Muscle weakness and associated diseases are likely to place a considerable economic burden on government health care expenditure. Therefore, our aim for this study was to estimate the direct and indirect costs associated with muscle weakness in the Czech Republic. We applied a cost-of-illness approach using data from the Survey of Health, Ageing and Retirement in Europe (SHARE). Six hundred and eighty-nine participants aged 70 years and over and without any long-term illnesses were included in our study. A generalized linear model with gamma distribution was used, and odds ratio (OR) was calculated in order to explore the effect of muscle weakness on direct and indirect costs. For both genders, muscle weakness had a statistically significant impact on direct costs (OR =2.11), but did not have a statistically significant impact on indirect costs (OR =1.08) or on total cost (OR =1.51). Muscle weakness had the greatest statistically significant impact on direct costs in females (OR =2.75). In conclusion, our study has shown that muscle weakness may lead to increased direct costs, and consequently place a burden on health care expenditure. Therefore, the results of this study could lead to greater interest in the prevention of muscle weakness among older people in the Czech Republic.


Subject(s)
Muscle Weakness/economics , Aged , Aged, 80 and over , Cost of Illness , Czech Republic/epidemiology , Europe , Female , Health Expenditures/statistics & numerical data , Health Surveys , Humans , Male , Muscle Weakness/epidemiology , Odds Ratio
10.
Folia Microbiol (Praha) ; 62(4): 335-342, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28213748

ABSTRACT

White rot fungi (WRF) are applicable to biodegradation of recalcitrant pollutants. However, excessive biomass growth typical for WRF cultivation can hinder their large scale applications. Therefore, immobilization of Irpex lacteus to liquid-core alginate beads restricting excessive mycelium growth and simultaneously keeping high degradation rate of pollutants was tested. Effective diffusivities of dyes to the beads varied from (2.98 ± 0.69) × 10-10 to (10.27 ± 2.60) × 10-10 m2/s. Remazol Brilliant Blue R (RBBR), Reactive Orange 16 (RO16), and Naphthol Blue Black (NBB) were used as model dyes. The immobilized fungus decolorized model dyes when applied both in microwell plates and in fluidized bed reactors. Using the microwell plates, the apparent reaction rate constants ranged from (2.06 ± 0.11) × 10-2 to (11.06 ± 0.27) × 10-2 1/h, depending on the dye used and its initial concentration. High initial concentrations negatively affected the dye decolorization rate. No fungal growth outside the beads was observed in fluidized bed reactors and thus no operational problems linked to an excessive biomass growth occurred. When RBBR was decolorized in subsequent batches in the fluidized bed reactor, the apparent reaction rate constant increased from (11.63 ± 0.35) × 10-2 to (29.26 ± 7.19) × 10-2 1/h.


Subject(s)
Coloring Agents/metabolism , Polyporales/metabolism , Water Pollutants, Chemical/metabolism , Alginates/chemistry , Biodegradation, Environmental , Cells, Immobilized/chemistry , Cells, Immobilized/metabolism , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Mycelium/chemistry , Mycelium/growth & development , Mycelium/metabolism , Polyporales/chemistry , Polyporales/growth & development
11.
Chem Biodivers ; 13(5): 582-90, 2016 May.
Article in English | MEDLINE | ID: mdl-27119624

ABSTRACT

Removal of selected metals from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied. The objective of the work was to determine the efficiency of Cu, Zn, Ni, Co, Sr, Li, and Rb removal, and to describe the main removal mechanisms. The highest removal efficiencies were attained for zinc and copper (89.8 and 81.5%, respectively). It is apparently due to the precipitation of insoluble sulfides (ZnS, CuS) in the vegetation bed where the sulfate reduction takes place. Significantly lower removal efficiencies (43.9, 27.7, and 21.5%) were observed for Li, Sr, and Rb, respectively. Rather, low removal efficiencies were also attained for Ni and Co (39.8 and 20.9%). However, the concentrations of these metals in treated water were significantly lower compared to Cu and Zn (e.g., 2.8 ± 0.5 and 1.7 ± 0.3 µg/l for Ni at the inflow and outflow from the wetland compared to 27.6 ± 12.0 and 5.1 ± 4.7 µg/l obtained for Cu, respectively). The main perspective of the constructed wetland is the removal of toxic heavy metals forming insoluble compounds depositing in the wetland bed. Metal uptake occurs preferentially in wetland sediments and is closely associated with the chemism of sulfur and iron.


Subject(s)
Wastewater/chemistry , Water Pollutants, Chemical/isolation & purification , Wetlands , Cobalt/chemistry , Cobalt/isolation & purification , Copper/chemistry , Copper/isolation & purification , Lithium/chemistry , Lithium/isolation & purification , Nickel/chemistry , Nickel/isolation & purification , Rubidium/chemistry , Rubidium/isolation & purification , Strontium/chemistry , Strontium/isolation & purification , Water Pollutants, Chemical/chemistry , Zinc/chemistry , Zinc/isolation & purification
12.
Bioresour Technol ; 203: 259-66, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26735881

ABSTRACT

Impact of strip gas composition on side stream ammonia stripping, a technology aiming at the reduction of high ammonia levels in anaerobic reactors, was investigated. Evaluation of the effect of oxygen contact during air stripping showed a distinct, though lower than perceived, inhibition of anaerobic microflora. To circumvent, the feasibility and possible constraints of biogas and flue gas as alternatives in side stream stripping were studied. Experiments, with ammonia bicarbonate model solution and digestate, were conducted. It was demonstrated that the stripping performance is negatively correlated to the CO2 level in the strip gas with a progressive performance loss towards higher concentrations. In contrast to biogas with its high CO2 content, the efficiency reduction observed for flue gas was significantly less pronounced. The later provides the additional benefit that its high thermal energy can be re-utilized in the stripping unit and it is therefore considered a viable alternative for air.


Subject(s)
Ammonia/chemistry , Biofuels , Bioreactors , Carbon Dioxide/chemistry , Conservation of Energy Resources/methods , Oxygen/chemistry , Waste Products
13.
Front Psychol ; 4: 240, 2013.
Article in English | MEDLINE | ID: mdl-23761768

ABSTRACT

This article investigates the relationship between visual mental representations and spatial mental representations in human visuo-spatial processing. By comparing two common theories of visuo-spatial processing - mental model theory and the theory of mental imagery - we identified two open questions: (1) which representations are modality-specific, and (2) what is the role of the two representations in reasoning. Two experiments examining eye movements and preferences for under-specified problems were conducted to investigate these questions. We found that significant spontaneous eye movements along the processed spatial relations occurred only when a visual mental representation is employed, but not with a spatial mental representation. Furthermore, the preferences for the answers of the under-specified problems differed between the two mental representations. The results challenge assumptions made by mental model theory and the theory of mental imagery.

14.
Article in English | MEDLINE | ID: mdl-23383641

ABSTRACT

Degradation of anionic and nonionic surfactants in a constructed wetland with horizontal subsurface flow was studied using high performance liquid chromatography and extraction spectrophotometry. The ratio of individual homologues of linear alkylbenzene sulfonates (LAS) and the efficiency of their removal were studied. Tridecyl-, dodecyl-, undecyl-, and decylbenzene sulfonates were removed with efficiencies of 92.9%, 84.3%, 64.7%, and 41.1%, respectively. These differences are due to sequential shortening of the alkyl chain in homologues during degradation (the higher homologue can provide the lower one). The formation of sulfophenyl carboxylic acids during ω-oxidation of the alkyl chain followed by successive α- and/or ß-oxidation is also a possible mechanism for removal of LAS. Solid phase extraction using Chromabond® HR-P columns was used for preconcentration of the analytes prior to their determination by HPLC. Methylene blue active compounds were determined using extraction spectrophotometry. The average efficiency of their removal was 84.9% in this case. The efficiency of nonionic surfactant removal (98.2%) was significantly higher in comparison to that for anionic surfactants. The concentration of the endocrine disruptor nonylphenol (a product of nonylphenol polyethoxylate surfactant degradation) determined in the profile of the wetland was beneath the limit of detection (0.4 µg/L). The average outflow concentrations of anionic and nonionic surfactants determined by spectrophotometry were 0.54 and 0.021 mg/L, respectively. The average outflow concentrations of decyl- and tridecylbenzene sulfonates determined by HPLC were 0.195 and 0.015 mg/L. Efficiencies of 86.4% and 92.2% were obtained for removal of organic compounds as indicated by chemical and biochemical oxygen demand (COD(Cr) and BOD(5)). These results demonstrate the suitability of the constructed wetland for degrading surface-active compounds.


Subject(s)
Chromatography, High Pressure Liquid/methods , Water Pollutants, Chemical/chemistry , Wetlands , Alkanesulfonic Acids/chemistry , Surface-Active Agents/chemistry
15.
Chem Biodivers ; 8(10): 1819-32, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22006711

ABSTRACT

Removal of nonionic surfactants from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied in 2009 and 2010. Extraction spectrophotometry with 3',3″,5',5″-tetrabromophenolphthalein ethyl ester and KCl served to determine the analyte concentrations. Triton(®) X-100 was used as a standard to express the nonionic-surfactant concentrations. Anionic and cationic surfactants were shown not to interfere during the determination. Nonionic surfactants were degraded (to products undeterminable by the method) with a high average efficiency that reached 98.1% in 2009 and 99.1% in 2010, respectively. The average concentration of nonionic surfactants at the inflow was 0.978 mg/l, while it was close to the limit of quantification at the outflow (0.014 mg/l). A significant fraction of nonionic surfactants (38.7%) was already degraded during the pretreatment, and only 14.0% of the nonionic surfactants remained in the interstitial H(2) O taken in the vegetation bed at a distance of 1 m from the inflow zone at a 50-cm depth. Nonionic surfactants were degraded both under aerobic and anaerobic conditions.


Subject(s)
Environmental Restoration and Remediation/methods , Surface-Active Agents/isolation & purification , Water Purification/methods , Octoxynol/isolation & purification , Rhizosphere , Surface-Active Agents/chemistry , Wetlands
16.
Chem Biodivers ; 6(9): 1350-63, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19774598

ABSTRACT

Removal of anionic surfactants from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied in 2007 and 2008. Extraction spectrophotometry with methylene blue served to determine the analyte concentrations in individual samples. The anionic surfactant-removal efficiency depended on actual conditions, mostly the treated water flow intensity, its temperature, and a redox-potential gradient in the longitudinal profile of the wetland bed. It increased with decreasing inflow and increasing temperature. The average efficiency was 83.7% in 2007 and 81.7% in 2008; however, values higher than 85% were often determined during the summer period. On the other hand, the efficiencies were usually lower than 80% in winter, especially in periods with intensive precipitation and inflows. The average concentration of anionic surfactants in water taken at the outflow was lower than 0.65 mg/l (expressed as sodium dodecyl sulfate). The most significant fraction of anionic surfactants (almost 50%) was degraded at the beginning (1 m from the inflow zone) of the wetland bed. The rhizosphere aeration via the vegetation roots strongly supported the anionic-surfactant removal.


Subject(s)
Surface-Active Agents/metabolism , Waste Disposal, Fluid/methods , Wetlands , Agriculture , Biodegradation, Environmental , Fluorescent Dyes/chemistry , Spectrometry, Fluorescence , Surface-Active Agents/chemistry
17.
Chem Biodivers ; 6(3): 341-55, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19319861

ABSTRACT

Constructed wetlands represent a progressive approach to the wastewater treatment. A fundamental prerequisite of the efficient water quality improvement is the presence of redox potential gradients (connected with the aeration of the system) inside the vegetation bed. Redox properties of a constructed wetland were tested in three longitudinal transects crossing the vegetation bed from the inflow zone to the outflow using diverse indicators (e.g., Fe(III)/Fe(II), SO(2-)(4)/S(2-)). Approximately 10-25% of iron was reoxidized in samples taken 10 m from the inflow zone in 2006. Redox processes of iron in artificial (constructed wetland) and natural (peat bog) ecosystems were compared. The peat bog was characterized with higher percentages of Fe(II) (usually ca. 90-100%). Thus, the aeration of the peat land was lower in comparison with the constructed wetland. The constructed wetland efficiently reduced sulfates (average concentrations of 44.7 and 11.2 mg/l at the inflow and the outflow, resp., in 2007). Organics, expressed as COD(Cr) and BOD(5), and NH+(4) were removed with efficiencies of 86.4, 92.2, and 60.4%, respectively. However, total phosphorus (redox processes play a negligible role in this case) was removed only with 39.6% efficiency. Redox properties of the wetland did not significantly depend on the heterogeneity of the treated wastewater flow.


Subject(s)
Ecosystem , Oxidation-Reduction , Plants/metabolism , Water Pollutants, Chemical/metabolism , Water Purification/methods , Wetlands , Aerobiosis , Anaerobiosis , Iron/metabolism , Manganese/metabolism , Nitrogen/metabolism , Phosphorus/metabolism , Soil , Sulfates/metabolism
18.
Chem Biodivers ; 4(12): 2900-12, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18081100

ABSTRACT

Constructed wetlands are very popular in terms of wastewater treatment today. Formation of redox potential gradients inside such a system strongly influences the wastewater-treatment efficiency. Individual oxidation forms of sulfur, and dissolved and precipitated manganese forms were determined in the vegetation bed of the constructed wetland. The aim of the speciation analysis was to contribute to the characterization of its redox properties. Sulfur was mostly oxidized at the inflow. The concentration of sulfates at the inflow varied from 25 to 55 mg/l, while concentration of sulfides was always lower than 6.0 mg/l and mostly even lower than 1.0 mg/l. However, sulfates were reduced during the pretreatment and the wastewater flow through the vegetation bed. The concentration of total manganese varied from 0.2 to 0.8 mg/l. Approximately 60% of Mn was precipitated at the inflow. The content of precipitated Mn forms declined to ca. 40-50% at the inflow zone, this content was almost constant across the vegetation bed to the outflow when water was sampled from 60-cm depth. However, the content of precipitated Mn forms increased to ca. 74% for samples from 20-cm depth. With respect to the aeration of the system, manganese can be precipitated as MnO2 in these samples.


Subject(s)
Manganese/chemistry , Sulfur/chemistry , Wetlands , Environmental Monitoring , Oxidation-Reduction , Seasons
19.
Chem Biodivers ; 3(12): 1288-300, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17193243

ABSTRACT

Wastewater-treatment processes taking place inside constructed wetlands are closely connected with chemical properties of these systems. The aeration of a wetland via the roots of the vegetation (and a subsequent formation of redox-potential gradients) strongly influences the wastewater treatment efficiency, and thus it represents one of the most important characteristics of the wetland. The concentration ratios of individual iron oxidation states (Fe(II) and Fe(III)) were determined as the indicator of the redox properties of the constructed wetland reed bed during this study. Interstitial water from the wetland was sampled eleven times throughout the year 2005. The spectrophotometric method using 1,10-phenanthroline was properly optimized (limits of detection and quantification, sensitivity, linear dynamic range, repeatability, and accuracy values were assessed) and applied for iron determination. Most of iron, ca. 98%, is reduced to the Fe(II) form in raw wastewater and water from the inflow zone of the constructed wetland, however, at the outflow and in the vegetation bed both iron oxidation states are usually detected. The presence of Fe(III) in the reed bed (ca. 10-30% for some samples) demonstrates the aeration of the wetland by the vegetation (Phragmites australis) resulting in a re-oxidation of Fe(II).


Subject(s)
Iron/chemistry , Oxygen/chemistry , Water Purification/methods , Biodegradation, Environmental , Chemistry/methods , Conservation of Natural Resources , Ecosystem , Oxidation-Reduction , Oxygen/metabolism , Phenanthrolines/chemistry , Reproducibility of Results , Spectrophotometry , Waste Disposal, Fluid , Water Movements , Wetlands
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