Metal Concentrations In Plants Research Articles

Combined application of two Bacillus species enhance phytoremediation potential of Brassica napus in an industrial metal-contaminated soil

This study aimed to assess the impact of individual as well as combined application of Lysinibacillus macroides and Bacillus safensis in phytoremediation potential of Brassica napus grown in soil contaminated by industrial effluents. In response to five metals; copper, chromium, nickel, lead, and cadmium, results revealed that germination percentage, fresh and dry weights, and photosynthetic pigments of B. napus decreased under contaminated soil. On the other hand, electrolyte leakage due to cellular injury, metabolites (proline and glycine betaine), antioxidant enzymes (superoxide dismutase, catalase, peroxidase, ascorbate peroxidase), accumulation of hydrogen peroxide and metals in plant’s roots, shoots and leaves increased. Inoculation significantly reduced these effects as proved by the enhancement of germination percentage, fresh and dry biomass, and photosynthetic pigments. Simultaneously, the antioxidant enzymes, metabolites contents (proline and glycine betaine) and metal concentrations in plant’s roots, shoots and leaves decreased. Combined application of both Bacilli strains was found more effective as compared to individual inoculation. It was concluded that metal resistant Bacillus species in combination had growth effects on B. napus and enhanced its phytoremediation efficiency in contaminated soil. Novelty statement Brassica napus; a hyper-accumulator of metals, loses phytoremediation potential with the passage of growth. Two Bacillus species (Lysinibacillus macroides and Bacillus safensis) having known bioremediation abilities were employed individually as well as in combination under metals contaminated soil to increase phytoremediation efficiency of B. napus. The metals containing soil used is a unique aspect in this study because selected soil, contaminated by industrial effluents, has not been evaluated or reported earlier. Combined application of Bacilli improved phytoremediation potential of B. napus more as compared to application of individual Bacillus strain which is yet another unique aspect of this investigation.

Physicochemical Characteristics and Heavy Metals Contents in Soils and Cassava Plants from Farmlands within Nnamdi Azikiwe University, Awka, Anambra State

Soil samples and cassava tubers collected from farmlands within Nnamdi Azikiwe University, Awka vicinity were analyzed for their heavy metal levels using Atomic Absorption Spectrophotometer (AAS) in order to assess their levels of contamination on the environment as a result of excessive fertilizers and automobile emission. Physiochemical properties of the soil samples were determined using standard methods. The soil pH had a mean value of 6.27 ± 0.07, 6.10 ± 0.06 and 6.57 ± 0.03 respectively indicating that the soils were slightly acidic to neutrality. Total organic carbon and nitrate mean values were 105.20 ± 6.20, 95.75 ± 9.57 and 94.6 ± 2.27 and 138.07 ± 12.09, 149.35 ± 14.25 and 149.20 ± 1.17 respectively showing presence of some organic matters. The mean levels of heavy metals in the soil samples were 0.01 ± 0.01, 0.05 ± 0.03 and 0.05 ± 0.03 for lead (Pb), 0.24 ± 0.16, 0.001 ± 0.001 and 0.001 ± 0.000 for cadmium (Cd) and 0.00 ± 0.00, 0.010 ± 0.006 and 0.001 ± 0.001 for chromium (Cr). These metals levels were in the abundance trend of Pb>Cd> Cr. The mean metal concentrations obtained in the cassava tubers respectively were 0.001 ± 0.001, 0.001 ± 0.001 and 0.005 ± 0.005 for lead (Pb), 0.000 ± 0.000, 0.0003 ± 0.0003 and 0.000 ± 0.000 for cadmium (Cd) and 0.002 ± 0.002, 0.000 ± 0.000 and 0.002 ± 0.002 for chromium (Cr). These metals levels were in the abundance trend of Pb> Cr > Cd. For both the soil and cassava samples, there were no significant variations in the heavy metal concentrations and also in physicochemical parameter except for pH; this showed that there is low heavy metal enrichment in the soils studied. Based on the study, the following heavy metals (Pb, Cd, and Cr) falls within the Codex maximum permissible limits 0.1mg/l or ppm expect soil cadmium in science village which is above the Codex limit. The overall results showed that the farmlands (on soils and cassava tuber) appear to be free from poisoning or some metal enrichment and safe for agricultural purposes and also safe for human health and consumption.

Toxicity Assessment of Waste From Mechanical Processing of Polymers by Biotesting

Background. Biotesting allows us to take into account the complex relationships between soil, pollution and living organisms, as well as to determine the impact of minimum concentrations of pollutants on ecosystems. It is more informative than determining the minimum concentration values. Objective. We are aimed to analyze the phytotoxicity assessment of sludge from mechanical processing of polymer mixtures extracted from solid household waste. Methods. The object of the study is waste from mechanical processing of polymer mixtures, represented by sludge after washing of crushed polymers, that is composed of particles of polymers of various compositions ranging in size from 0.5 to 2.7 mm (87.3 to 92.6 % of the total amount), as well as residues of paper labels from 7.4 to 12.6% of the total amount. The assessment of phytotoxic effects was carried out by vegetative methods in accordance with ISO 17402-2008, ISO 17126-2005a, ISO 22030:2005b, ISO 11269-1:2012a, MP 2.1.7.2297-07 "Guidelines. Justification of the hazard class of production and consumption waste by phytotoxicity". The contamination levels of the test samples were assessed according to ISO 11269-2:2002 and MR 2.1.7.2297-07. Biotesting was carried out on the following types of plants: watercress, mustard, wheat, corn, soy, barley. The study of the content of heavy metals (Pb, Cu, Cd, Zn, Ni) was carried out by atomic absorption method with a spectrophotometer of the CAS-120.1 type. The obtained results were processed using traditional statistical methods applying licensed computer programs Microsoft Excel and StatSoft STATISTICA 10.0.1011.0. Results. The studied sludge does not have a negative effect on the process of germination of watercress, mustard, corn. The level of phytotoxic effect of sludge on the germination of soybeans and barley was within the permissible range and did not exceed 3.33 %. When assessing the vegetative properties of the studied plants, it was found that in the process of growing corn, wheat, barley and soy, the sludge does not have a phytotoxic effect. When the concentration of added sludge changed, the phytotoxic effect on the length of the roots and stems of watercress and mustard was medium (cress) and weak (mustard). The study of the migration of heavy metals present in the growth substrates and their accumulation during the growth and development of plants showed an insignificant content of heavy metals in plants in all the studied samples with different sludge content. The lead content is 1.83 times higher compared to the control samples and 2.13 times higher compared to the samples on "conditionally clean" soiland 14% lower compared to the norms of SRN 42-123-4089-86 "MAC of heavy metals and arsenic in food raw materials and food products". Conclusions. The assessment of the phytotoxic effect of the sludge obtained in the process of mechanical processing of polymer raw materials has established that it is rational to determine the phytotoxicity of this type of sludge on the germination process and vegetation changes of plants on the most sensitive crops, such as cress and mustard. The mobile forms of lead that migrates from plant substrates and sludge into plants and accumulates in them are determined. Migration of bound forms of heavy metals copper, nickel, cadmium and zinc has not been established.

Toxic Elements in Soil and Rice in Ecuador

The concentration of trace toxic metals (Cr, Zn, As, Pb, Cd, Cu, and Ni) in soil and rice plants, including the stems, leaves, and grain, from the main rice-producing provinces in Ecuador, was determined. Additionally, the soils were analyzed to determine their properties, composition, total content, bioavailable fraction, and geochemical fractions of toxic elements. Approximately 30% of soil samples in the case of Cr and Cu and 10% of samples in the case of Ni exceeded the legal thresholds for Ecuador. Moreover, for Cr and Cu, approximately 4% and 13% of samples, respectively, exceeded the threshold value of 100 mg kg−1 proposed for these two elements in several international regulations. Concentrations of As, Pb, and Cd in the soils were below the threshold values established both by Ecuadorian laws and by other countries. The concentrations of metals in rice plants did not correlate linearly with the total metal concentrations in the soil, nor with their bioavailability. However, the bioconcentration factors for As, Cd, Cu, Ni, and Zn could be predicted from bioavailability by a power law with exponents ranging from −0.724 to −1.625, which is typical of accumulator plants, where trace metal homeostasis plays an important role.

Effect of biomass fly ashes from fast pyrolysis bio-oil production on soil properties and plant yield

A globally increased demand for fuels and environmental concerns regarding fossil sources call for sustainable alternatives. Fast pyrolysis is a promising approach for converting different types of biomass to renewable Fast Pyrolysis Bio-Oil (FPBO) that can be used for heating, power generation and mobility. Side-products emerging from the process include low calorific gases and charcoal. Both are further combusted to generate energy for the process. From the charcoal, the process leaves behind fly ashes (FAs) that contain macro- and micronutrients. In this regard, FPBO-FAs might present valuable soil fertilizers, but also bear the risk of soil heavy metal (HM) contamination. In this study, the risk and potential benefit of FPBO-FAs derived from three different biomass sources (bark, forest residue and Miscanthus sp.) as soil amendments was tested. Twice, in autumn 2017 and 2018, FPBO-FAs were applied to the field (500 kg ash ha−1 y−1) in a grassland experiment. Neither physico-chemical and microbiological soil properties nor plant yield were affected following FPBO-FAs application. Seasonal differences and changes from year to year, however, were evident, both for some soil and plant properties. The lack of effects on (i) plant yield, (ii) soil microbiological and physicochemical properties, (iii) heavy metal concentrations in soil and plant suggest that the product may safely be applied. The fact that these field-trial results are in discordance with previous greenhouse trials suggest, however, that long-term trials would be needed.

Evaluation of metal accumulation in the forage grass Brachiaria decumbens Stapf grown in contaminated soils with iron tailings.

The biggest world tailing dam rupture occurred in Brazil in 2015, releasing approximately 32 million m3 of iron tailings in the Doce River watershed, along its 660 km trajectory, reaching the Atlantic Ocean. This disaster significantly altered water and soil properties, increasing the soil metal contents, mainly iron concentration. Little is known about the concentration of toxic elements in plants grown in these areas. Brachiaria decumbens stands out as the most cultivated grass in the affected areas and is widely used for cattle grazing. This study verified the metal contents in soils and in samples of B. decumbens grown in the initial pathway of the debris flow. It was noted that the tailingdeposition altered the substrate chemically, increasing Fe by 181% and reducing Zn soil contents by 188%. However, the metal contents in the forage grass were below the toxic limit for cattle feed. In addition, the results suggest that the natural geological characteristics of the region also influenced the metal contents in plantssince those plants grown in nonaffected areas also showed high metal concentrations. The impacted area soils had a slightly basic pH, which can reduce the metal availability. Considering that, in the future, these soils would return to their natural acid state, the metal contents in plants grown in the affected regions could probably increase. Thus, long-term studies are needed to ensure the food safety of the forage production in these areas. Integr Environ Assess Manag 2022;18:528-538. © 2021 SETAC.

Effects of Different Types of Organic Fertilizer on Biomass Yield, Bioactive Compounds and Heavy Metals Contents of Phyllanthus Niruri

This research aimed to study the effects of different types and rates of organic fertilizer on biomass yield, bioactive compounds, and heavy metals content of Phyllanthus niruri. Two types of organic fertilizers (animal-based and plant-based) with five different rates (0, 100, 200, 300, and 400 kg N ha−1) were used in this study. There was an interaction between fertilizer types and rates on biomass yield, heavy metals content, and bioactive compounds. Plants are grown with 400 kg N ha−1 of animal-based fertilizer, and plant-based fertilizer produced the highest fresh biomass. However, phyllanthin and hypophyllanthin concentrations of P. niruri were not affected by applying animal-based and plant-based fertilizers at all rates. In addition, Cd and Pb concentrations also decreased with the increasing rate of organic fertilizer and were below the Malaysia Permissible Levels (MPLs). Therefore, animal-based fertilizer at 400 kg N ha−1 was selected as the optimum rate due to its reduced heavy metal concentration in plants and higher phyllanthin and hypophyllanthin yield.

Analysis of Heavy Metals Levels in Locally produced Rice Fumigated with Cypermethrin (Pyrethroid) Pesticide Grown in Auyo Rice Field of Jigawa State

There is a growing public concern over the potential accumulation of heavy metals in agricultural soils owing to rapid urban and industrial development and increasing reliance on agrochemicals in the last several decades. Excessive accumulation of heavy metals in agricultural soils may not only result in environmental contamination, but elevated heavy metal uptake by crops may also affect food quality and safety. The present study aims to study heavy metal concentrations in rice parts (root, stem, leaf, seed and corresponding soils in the Auyo rice field. Specimens of rice plant parts from different locations in 10 × 10 m were sampled with their corresponding soils. Soil and plant specimens were analysed by using Atomic Absorption spectrometry. It was found that metal concentration in soil was highly variable while the concentration of metals in plants directly depends on the concentration of metal-based pesticide applied. Roots showed the highest metal concentration, followed by leaves, stem and seeds. The physicochemical parameters of the soil from the study area revealed that the pH of the soil sample is within the alkaline range. Similarly, the electrical conductivity was less than 4 (0.51 to 0.65 dSm-1), indicating the presence of soluble salts within average, dissolved Nitrogen at a range of 179.4 to 221 kg/Ha, showing low in nitrogen content, Phosphorus levels in the study region range from 29.00 to 42.33 kg/ha, while potassium level in the soil varies from 126.22 to 250 kg/ha. In general, the soil in the study area was found to be very rich and fertile for the cultivation of rice. The accumulation of some heavy metals in some rice parts may be due to the effects of cypermethrin pesticides.

Biochemical Responses of Medicinal Plant Tussilago farfara L. to Elevated Heavy Metal Concentrations in Soils of Urban Areas.

This study was conducted in Tyumen (Russian Federation) to establish the effects of heavy metals’ (Cu, Zn, Fe, Mn, Pb, and Cd) accumulation in soil and coltsfoot, as well as plants’ biochemical responses to such an accumulation. The mobile and acid-soluble heavy metal fractions in soils, and the heavy metal contents in plants, were determined by atomic absorption spectrophotometry. The Cu, Zn, Fe, Mn, and Pb concentrations in soils exceeded background values. Pb content at the battery manufacturing plant was above the maximum permitted concentration. The percentages of the mobile heavy metal fractions decreased in the following order: Mn > Zn > Cu > Fe. The greatest heavy metal accumulation in soils and plants was found at the battery manufacturing and metallurgical plants examined in our study. Heavy metals’ accumulation in the aboveground part of Tussilago farfara decreased in the following order: Fe > Zn > Cu > Mn > Pb > Cd. The accumulation of heavy metals stimulated the synthesis of photosynthetic pigments by 6–30%. Heavy metals provoked oxidative stress in cells, increasing the concentration of lipid peroxidation in products by up to 80%. Plant phenolics and flavonoids in the urban area of our study decreased compared to those in the control by 1.05, reaching up to 6.5 times. The change in coltsfoot catalase activity both increased and declined. Biochemical responses and heavy metal accumulation in coltsfoot from urban areas limit its use for medicinal purposes.

Phytoremediation potential of the naturally occurring wetland species in protected Long Beach in Ulcinj, Montenegro

Long Beach, situated in southern Montenegro, is subject to considerable biogenic and abiogenic influences. Thus, analyzing total heavy metal content in soil and plants in this region is, while challenging, highly important in order to assess the level for determining the soil degradation level and the phytoremediation potential of naturally growing salt marsh species. This area together with a Bojana river and backshore forms a real vegetation mosaic where habitats of various types coexist. Therefore, it represents good model system. In the present study, the levels of As, Al, B, Cd, Co, Cr, Cu, Hg, Fe, Mn, Mo, Ni, Pb and Zn in coastal soils as well as in eight salt marsh plants: Bolboschoenus maritimus, Juncus acutus, Juncus anceps, Juncus articulatus, Juncus gerardii, Juncus maritimus, Scirpus holoschoenus and Schoenus nigricans, were investigated in order to identify the plant species that can be used for the remediation of polluted sites, especially those located along the coastline. The obtained results show that species J. gerardii, J. articulatus and B. maritimus can be clearly separated from J. acutus, J. anceps, J. maritimus, S. holoschoenus and Sh. nigricans based on the degree of heavy metal accumulation in various organs. Moreover, analyses revealed that the bioaccumulation factor of underground organs is significantly higher relative to that of the aboveground parts for almost all investigated metals and species. The bioaccumulation factor had the highest value in the underground organs of J. gerardii and B. maritimus, where a value of 3.37 was measured for B and 2.54 for Hg, respectively. Hence, as all investigated species are “underground accumulators” for most of the analyzed metals, they could be useful for phytostabilization and phytoremediation of B and Hg in particular. Moreover, each plant species can be used in the phytoremediation process targeting specific heavy metals.

GEO- AND PHYTO-MONITORING OF ENVIRONMENTAL IMPACT OF SMELTING INDUSTRY IN IKIRUN, NIGERIA

This research monitored the level of some heavy metals in soil and a plant species around iron smelting industry. The soil in different depths D1 (0 -10 cm), D2 (10 – 20 cm) and D3 (20 -30 cm) and plant (Tithonia diversifolia) known as Mexican sunflower were sampled in four soil sampling points (SSP) and plant sampling points (PSP) which are 50, 100, 150 and 200 m away from the industry. The concentrations of Cr, Cu, Fe, Pb and Zn in the soil and plant digest were determined using Atomic Absorption Spectroscopy (AAS). Some physicochemical properties like pH, electrical conductivity and organic matter were also measured. The result of the analysis of the heavy metals in the soil was in the sequence Fe > Zn > Cu >Pb> Cr at SSP1 SSP2 and SSP4 while Fe > Zn > Cu > Cr > Pb at SSP3. In the plant, the result showed the presence of these heavy metals except Pb which was not present in any sampling points. The concentration of iron (Fe) in the plant decreased away from PSP1 to PSP4 around the industry. The physicochemical properties like pH which influenced the availability of metals in soil were found to increase away from SSP1 to SSP4 and consequently its effect on the concentration of these heavy metals in plants, particularly for Fe and Zn. Although, heavy metals monitored were within the permissible limit of WHO except Fe in soil, the trend of their presence in

Heavy metal pollution of dumpsite soil of Kogi State University, Ayangba

The research aims to assess the local addition of selected heavy metals (Pb, Cd, and Cu) when dumpsite soil is used as a soil amendment and the ability of Amaranth (NH536–1) to phytoremediate the soil. It was a pot experiment conducted at Kogi State University's Faculty of Agriculture in Ayangba. The soil samples were collected from a dumpsite and arable soil. The dumpsite soil application to the arable soil was at different rates:10kg Arable soil (Treatment 1, control), 8kg Arable soil+ 2kg Dumpsite soil (Treatment 2), 6kg Arable soil+ 4kg Dumpsite soil (Treatment 3), 4kg Arable soil + 6kg Dumpsite soil (Treatment 4), 2kg Arable soil+ 8kg Dumpsite soil (Treatment 5) and 10kg Dumpsite soil (Treatment 6). The result shows that the concentration of heavy metals: Lead (Pd), Cadmium (Cd), and Copper (Cu) increased significantly as the concentration of dumpsite soil increased. Lead (Pb) has the highest concentration, while copper (Cu) has the lowest concentration. The result also shows that the plant's metal concentration depends on their concentration in the habitual soil environment. Thus, the Amaranth was able to show phytoremediation potential on soil heavy metals content. The trend of Amaranth potential phytoremediation heavy metals from the soil is in the sequence Lead Pb> Copper (Cu) >Cadmium (Cd).

Heavy metal accumulation characteristics and physiological response of Sabina chinensis and Platycladus orientalis to atmospheric pollution

Heavy metal (Cu, Mn, Zn, Pb, and Cd) concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban, suburban, and rural sites in Tianjin, China. Photosynthetic pigment contents, reactive oxygen species content, malondialdehyde (MDA) content and antioxidant enzyme activity were investigated, providing physiological response parameters. Our comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant leaves. At the rural site, both plant leaves exhibited the lowest heavy metal accumulation. The highest Cu, Mn, and Zn concentrations were found in S. chinensis leaves from the urban site; the highest Pb and Cd concentrations were found in P. orientalis leaves from the urban site. These results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission gradient. It is also found that S. chinensis may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals, while P. orientalis may be used for mitigation due to its high resistance. The results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.

Evaluation of phytoremediation potential of native dominant plants and spatial distribution of heavy metals in abandoned mining area in Southwest China

A field investigation on the content of heavy metals in soils and dominant plants was conducted in three sites (A<0.5 km, B<1.0 km, C<1.5 km) with different distances of mine tailings. The spatial distribution of heavy metals and the accumulation in plants were compared, and the candidate species for ecosystem restoration were selected. The results indicated that the soil was polluted by chromium (Cr), Cadmium (Cd), copper (Cu), nickel (Ni) in varying degrees, which is 2.07, 2.60, 1.79, and 4.49 times higher than the Class-Ⅱ standard in China. The concentrate of Ni, Cd, and Zinc (Zn) increased, while Cr, Lead (Pb), and Cu decreased with the distance from the mine tailings. 73 species (34 families) were found and mainly herbaceous plants. The concentrate of Cd, Cu, Cr, and Ni in 29 dominant plants were measured and 66.67%, 21.43%, 100%, 47.62% plants exceeded the normal concentration range. Based on the comparative analysis of heavy metal content, bioconcentration factor, and translocation factor in plants, Polygonum capitatum has good phytoextraction ability, Boehmeria nivea, Chrysanthemum indicum, Miscanthus floridulus, Conyza canadensis, Rubus setchuenensis, Senecio scandens, and Arthraxon hispidus showed remarkable phytostabilization abilities of Cr, Cd, Ni, and Cu, which can be used as potential phytoremediation candidate.

Use Bottom Sediment to Agriculture—Effect on Plant and Heavy Metal Content in Soil

Removing bottom sediment from water reservoirs and rivers can, on the one hand, be an effective method to restore lakes, and on the other—be used for plant production, ensuring the recycling of nutrients. The aim of this research was to evaluate the possibilities of using various types of bottom sediment and its impact on heavy metal content in soil and plants. For this purpose, a pot experiment was carried out using white mustard (Sinapis alba) as a test plant. The total content of heavy metals (Cd, Cu, Zn, Pb) was determined in soil and plant. The addition of all types of bottom sediment increased heavy metal content in the soil. The results indicate that adding bottom sediment resulted in a significant increase in plant yield in comparison to the control. The highest yield as a result of direct effect was obtained for a combination with a 5% addition of dam sediment, while as a result of residual effect, the highest yield was achieved for a mixture with a 10% addition of pond sediment. The values of the transfer factor (TF = Cplant/Csoil) indicate a high accumulation of zinc and low accumulation of lead in the plant.

The multi metal-resistant bacterium Cupriavidus metallidurans CH34 affects growth and metal mobilization in Arabidopsis thaliana plants exposed to copper.

Copper (Cu) is important for plant growth, but high concentrations can lead to detrimental effects such as primary root length inhibition, vegetative tissue chlorosis, and even plant death. The interaction between plant-soil microbiota and roots can potentially affect metal mobility and availability, and, therefore, overall plant metal concentration. Cupriavidus metallidurans CH34 is a multi metal-resistant bacterial model that alters metal mobility and bioavailability through ion pumping, metal complexation, and reduction processes. The interactions between strain CH34 and plants may affect the growth, metal uptake, and translocation of Arabidopsis thaliana plants that are exposed to or not exposed to Cu. In this study, we looked also at the specific gene expression changes in C. metallidurans when co-cultured with Cu-exposed A. thaliana. We found that A. thaliana’s rosette area, primary and secondary root growth, and dry weight were affected by strain CH34, and that beneficial or detrimental effects depended on Cu concentration. An increase in some plant growth parameters was observed at copper concentrations lower than 50 µM and significant detrimental effects were found at concentrations higher than 50 µM Cu. We also observed up to a 90% increase and 60% decrease in metal accumulation and mobilization in inoculated A. thaliana. In turn, copper-stressed A. thaliana altered C. metallidurans colonization, and cop genes that encoded copper resistance in strain CH34 were induced by the combination of A. thaliana and Cu. These results reveal the complexity of the plant-bacteria-metal triad and will contribute to our understanding of their applications in plant growth promotion, protection, and phytoremediation strategies.

Assessment of the Streptomyces-plant system to mitigate the impact of Cr(VI) and lindane in experimental soils.

Phytoremediation techniques have been proposed as ecological methods to clean up contaminated sites. This study is aimed to evaluate the effect of the Streptomyces sp. Waksman & Henrici and Zea mays L. plant system on the dissipation of Cr(VI) and/or lindane from a co-contaminated soil, being 2mgkg-1 of lindane and 150mgkg-1 of chromium used. Lindane dissipation was improved in the presence of plant-microorganism association; however, Cr(VI) removal was higher when plants or the microorganism were separately. In co-contaminated systems, chromium content in plant tissues was lower than metal content in plants grown only with Cr(VI), suggesting that lindane could interfere with metal accumulation in the plant. The high malondialdehyde (MDA) concentration detected in non-inoculated plants grown with chromium could be consequence of high metal concentration in plant tissues. Interestingly, plants inoculated with Streptomyces sp. Z38 growing with Cr(VI) showed decrease in MDA concentration, indicating that the bacterium could activate defense mechanisms in the plant. Also, inoculated plants showed the highest value of superoxide dismutase activity. Lettuce plants used as bioindicators grew better in biologically treated soils compared with lettuce grown on non-treated soil. The results presented in this work provide the basis that will allow the optimization of future trials on a larger scale.

Influence of electrical fields enhanced phytoremediation of multi-metal contaminated soil on soil parameters and plants uptake in different soil sections

The influence of electrical fields on phytoremediation of multi-metal (Cd, Cu, and Zn) naturally contaminated soils has been investigated based on different soil sections. After ryegrass and hybrid penisetum were sowed for 30 d, electrical fields were applied during 30 days with the switching polarity every 30 min and continuing for 16 h d−1. After electrokinetic (EK) assisted phytoremediation process, soil electrical conductivity (EC) in anode section and available soil potassium (K) in cathode section were obviously elevated. Plants biomass in middle and cathode sections were increased in both plants, especially in middle section the overall biomass of hybrid penisetum increased by 68.8%. The influence of electrical field on the contents of heavy metals in plants was different depending on the species of plants, kind of heavy metals and soil section. For Cd, Cu, and Zn co-contaminated soils, shoot metals accumulation in middle section in both plants were improved at least about 20% (with the exception of Zn in ryegrass). Electrical fields had the most significant effect on copper absorption by ryegrass and shoot Cu accumulation were elevated 32.5% in all the section. The soil EC maybe an important factor that affected electrical fields enhanced plants growth, plant metals concentrations and remediation efficiency.

Analysis of Heavy Metal Content in Soil and Plants in the Dumping Ground of Magnesite Mining Factory Jelšava-Lubeník (Slovakia)

A high content of heavy metals in the soil and plants of a magnesite mining area might cause serious damage to the environment and can be a threat to the health of the surrounding population. This paper presents the results of research that focused on analyzing the heavy metal content in soil and plants in the dumping grounds of the magnesite mining factory Jelšava-Lubeník (Slovakia). The analysis focused on the content of heavy metals in soil (X-ray fluorescence spectrometry, atomic absorption spectrometry), in plants (inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission spectrometry), and pH (1M KCl solution). The results showed that the soil in the study area was slightly acidic to strongly alkaline and the content of Cr, As, Mn, and Mg exceeded by several times the limit values for the Slovak Republic. The results of the hierarchical cluster analysis and the correlation analysis show that the grouped metals come from the same sources of pollution. The content of heavy metals in plants was high and the highest concentration was found in the roots of Elytrigia repens &gt; Agrostis stolonifera &gt; Phragmites australis and flowers of Phragmites australis. The findings confirmed the suitability of the used plants in the process of phytoextraction and phytostabilization. The acquired knowledge can help in planning and realization remediation measures and improve the state of the environment in areas exposed to magnesite mining.

ECOLOGICAL AND GEOCHEMICAL EVALUATION OF THE HEAVY METALS CONTENTS IN THE COMPONENTS OF THE LANDSCAPE IN KIVERTSI NATIONAL NATURE PARK “TSUMANSKA PUSHCHA”

The study presents the results of the spatial distribution of the heavy metal contents in separate components of the landscape of Kivertsi National Nature Park “Tsumanska Pushcha”. The article provides the quantitative indices of the heavy metals contents, which represent the intensity, character, and specificity of the accumulation in the soil horizons. Concentrations of the microelements fluctuate depending on the lithological type of deposits, their facies affiliation, and localization in the drainage basin. The contents of nickel, cobalt, lead, chromium, vanadium, manganese, and copper are characterized by significant divergence from their average concentrations, though it doesn’t exceed their estimated abnormal indices. Most of the studied heavy metals in the soil exceed the regional geochemical background. The biggest accumulation of copper and zinc is taking place in the forest floor, and the mineral part of the profile is lightly marked by alluvial and illuvial character. The contents of nickel, cobalt, and manganese are increasing with the depth with the accumulation of these elements, which are typical of the chemical contents of glacial deposits. The forest floor is distinctly playing the role of a barrier that prevents copper from penetration into the inner levels of occurring soil horizons. The paper defines the dependence of the heavy metal contents in plants of the national nature park on the level of technogenic load and characteristics of the soil covering of the territory. With the increase of the heavy metals in soil, they accumulate in plants. Though, with the distance from the source of contamination, the contents of the heavy metals in plants decrease by 10-20 mg/kg. The study of the most common plants, which grow on the soils of diverse mechanical contents, revealed that the plants which grow on sod-podzolic sandy soil display the biggest number of microelements, while those growing on bog soil and peat bogs. The main part of the exceeding background indices according to the elements has been found in sample areas westwards. All plants under research accumulated Mn, Cu, Cr to a maximal extent while Zn and Ti to a minimal extent, which is in accordance with elements migration of this group. The main directions of further research include the study of heavy metals distribution in diverse genetic types of the soils; definition of the standard contents of the elements in geochemical landscapes needed to identify the intensity of migration and character of elements distribution; performance of biochemical zoning.