Metal Concentrations In Soils Research Articles

Assessment and Source Analysis of Heavy Metal Pollution in Farmland Soil Around Tin Mine

Studying the status and source analysis of heavy metal pollution in farmland in typical mining and processing areas is an important prerequisite for promoting farmland soil ecological restoration and farmland protection in concentrated mining areas. In this study, the heavy metal content of farmland soil around a mining area in southwest China was detected, and the pollution status, distribution law, health risks, and sources of heavy metals were studied by using the land accumulation index method, comprehensive pollution index method, kriging interpolation method, health risk assessment method, and PMF receptor model on the sampling data. The results showed that the mean values of eight heavy metals in farmland soil except Ni exceeded the local soil background values, and the results of the ground accumulation index evaluation showed that Cd and Hg were extremely polluted； Pb and As showed medium pollution-heavy pollution； and Cr, Zn, Ni, and Cu were lightly polluted. In the health risk assessment, oral ingestion was the main exposure route posing a health risk to the human body； the main element that constituted non-carcinogenic health risks was As, and the carcinogenic risks were from As and Cd. PMF model analysis showed that the contribution rate of weathering natural sources of iron-bearing ore was 28.02%, and the main factors were Ca and Fe. The contribution rate of agricultural sources was 3.02%, and the main factors were Pb and As. The contribution rate of industrial and atmospheric deposition composite sources was 33.09%, and the main factor was Hg. The contribution rate of the parent material source was 17.27%, and the main factor was Ca. The contribution rate of mining activities such as mining and smelting was 18.60%, and the main factors were Zn and Cd.

Heavy Metal Pollutants Or Contaminant In Soil Samples Obtained From Wash Boreholes Within Pantisawa, Yorro L.G.A. Of Taraba State

The problem of environmental pollution and its compartments due to an increase in contamination as a result of the accumulation of heavy metals and microorganisms from soil has raised wide-spread of concerns in different parts of the nations and this has compromised the ability of the environments to foster life and render them an intrinsic value. Hence the study aimed to ascertain the level of environmental pollution in soil from wash borehole within Pantisawa Yorro Local Government Area of Taraba State, Nigeria. A total of 45 samples for soil were collected aseptically from the five different zones (Pantisawa Main Market YM, Kapazang YG, Dola YD, Kallau YK and Zabi YZ) of Pantisawa. The levels of trace metals in soil samples were determined using Atomic Absorption Spectroscopy (AAS) PG-990. The results were analyzed using SPSS Version 20. The soil samples result for these metals revealed that iron concentration was between 3000-4010mg/kg most especially for site SD which is higher than all other elements analyzed. Zinc ranges from 2.54-6800mg/kg which is above the standard as prescribed by WHO and FEPA in soil and also exceeded the dutch target values of (Zn: 50mg/kg and Cu: 30mg/kg) in some of the sampling sites. Nickel was between 8.47-19.09 mg/kg in soil samples, this is below the toxicity threshold limit of 35mg/kg for safe environment as stated by WHO. Arsenic ranges from 53.06mg/kg–141mg/kg, which is higher than the admissible limit of 50mg/kg in soil recommended by UNEP. The order of all the metal concentration in the areas was Fe>Zn>Mn>As>Pb>Cu>Mn>Co and Cd respectively. Based on this study, the high concentration of the metals such as Zn, As, Cd, Pb, and Co in some of these sites most especially SK, SM and SD within Pantisawa revealed that some of the soil samples collected from these areas were contaminated with heavy metal pollutants which may have serious health risk to the people using it for various activities. The higher concentrations of these toxic metals in soils need to be monitored regularly for heavy metal enrichment.

Pollution characteristics of heavy metals, antibiotic and antibiotic resistance genes in the crested ibis and their habitat across different lifestyle and geography

Antibacterial resistance in wild animals has been increasingly reported worldwide, even though they are usually not directly exposed to clinically relevant antibiotics. Crested ibis, one of the rarest birds in the world, usually forages in paddy fields and prefer to nest and breed near villages that is greatly influenced by anthropogenic activities. We sampled the feces of crested ibises, as well as their habitat environment samples, to explore the pollution characteristics of heavy metals, antibiotics and antibiotic resistance genes (ARGs). Results showed that the pollution characteristics of heavy metals, antibiotic, ARGs and gut microbiota of crested ibis were more related by host lifestyle and habitats. Captive ibises had higher relative abundances of the total ARGs and tetracycline concentrations compared with feralization and wild ibises, while the heavy metal contents had shown the opposite result. The Characteristics of pollutants in the corresponding environmental samples also exhibited high similarity with the results of fecal samples. The relative abundances of Proteobacteria and Actinobacteria were significantly different between captive and wild individuals, while the abundance of majority bacterial genera was generally higher in wild populations. The concentrations of heavy metals in soil (Cd, Cu and Zn) and water (Cd, Cu, Zn and Cr) were both exceeded the background soil levels or surface water quality standards, suggesting multi-element contamination in the habitat. Ecological risk assessments of soils by Igeo and Er showed that the habitats of wild ibises were heavily and moderately contaminated by Cd, which would possibly pose a threat to the health of ibises. PLS-PM analysis indicated that microbial compositions and residual antibiotics had the most substantial impact on the dynamic changes in ARGs of ibis. Overall, this work provides a comprehensive understanding of the characteristics, risks of those contaminations, and their effects on the ARGs in the habitat of crested ibis.

Effect of Multi-Year Protection of Grapevines with Copper Pesticides on the Content of Heavy Metals in Soil, Leaves, and Fruit

This study evaluates the impact of multi-year protection of grapevines using copper-based pesticides on heavy metal content in soil, leaves, and fruit under organic and conventional cultivation methods. Conducted on Solaris, Hibernal, and Muscaris grapevine varieties in north-western Poland, the research highlights significant differences between the two cultivation approaches. In organic vineyards, copper content in soil averaged 10.25 mg/kg, significantly higher than the 9.05 mg/kg found in conventional soils. Manganese levels were also elevated in organic soils (223 mg/kg) compared to conventional ones (299 mg/kg). Conversely, conventional vineyards exhibited higher zinc and lead concentrations, averaging 47.10 mg/kg and 20.34 mg/kg, respectively, versus 43.50 mg/kg and 11.22 mg/kg in organic soils. The organic soils also had higher salinity (46.50 mg/kg) than conventional ones (30.50 mg/kg). The fruits of grapevines in organic cultivation showed higher copper and zinc levels, with the Solaris variety containing 15.01 mg/kg of copper and the Muscaris variety having 11.43 mg/kg of zinc. These levels exceed the commonly encountered ranges of <1 to 10 mg/kg. Lead content in fruits was higher in organic cultivation (2.19 mg/kg) than in conventional cultivation (1.18 mg/kg), occasionally surpassing the critical value for consumable plants (1 mg/kg). Leaves of grapevines from organic vineyards had significantly higher copper and manganese content than those from conventional vineyards, with the Hibernal variety showing the highest levels. These findings underscore the necessity for monitoring and managing heavy metal content in vineyard soils to ensure fruit quality and safety.

Polycyclic aromatic hydrocarbons and trace metals contents of Pterocarpus Mildbraedii and Ocimum gratissimum grown near markets within Aba Metropolis, Nigeria: An evaluation of dietary intake risks

Consuming contaminated vegetables is one recognised method that people are exposed to polycyclic aromatic hydrocarbons (PAHs) and trace metals (TMs). For this reason, it is important to constantly keep an eye out for these potentially fatal toxins in vegetables. Eighteen PAHs and TMs were investigated in the leaves of Pterocarpus mildbraedii and Ocimum gratissimum grown near Afule, Ahiaohuru, and Umuocham market locations within Aba metropolis using high-performance liquid chromatography (HPLC) for PAHs while an Inductively Coupled Plasma Optical Emission Spectrophotometer (ICP-OES) for trace metals and Hg was analysed using a Cold Vapour Atomic Fluorescence Spectrophotometer (CV-AFS). The results from the study showed that Afule samples gave (mg kg-1 PAHs) 6.84, 8.12; Ahiaohuru samples gave (mg kg-1 PAHs) 11.34, 17.68; and Umuocham samples gave (mg kg-1 PAHs) 0.17, 0.16 for P. mildbraedii and O. gratissimum leaf samples, respectively. As per the estimated data, the concentrations of trace metals in vegetables and soil are found in the range of 0.432–6.03 mg/kg for Al, 0.133–0.867 mg/kg for Cd, 0.003–0.840 mg/kg for Co, 1.400–2.933 mg/kg for Cr, 0.933–4.533 mg/kg for Cu, 132.233–198.197 mg/kg for Fe, BDL–0.0002 mg/kg for Hg, 0.002–0.004 mg/kg for Li, 8.007–19.067 mg/kg for Mn, 0.533–1.633 mg/kg for Pb, 0.300–0.667 mg/kg for V, and 2.050–6.103 mg/kg for Zn. The trace metals observed are compared to the literature reported values. It was discovered that the average metal concentrations were below the FAO/WHO maximum allowable values. Every metal in the study had estimated daily intake (EDI) values that were lower than the reference oral dosage (RfD) for that metal. The health risk index (HRI), target health quotient (THQ) and hazard index (HI) values for both vegetables were much lower than 1 implying that the exposed population is safe from potential toxic metal.

Inter- and intra-specific metal tolerance variation in ectomycorrhizal fungal Suillus species.

Soil metal contamination can affect growth, metabolism, and reproduction of organisms, and can lead to death. However, some fungi have evolved metal tolerance and are able to live in contaminated soils. Species in the ectomycorrhizal genus Suillus from Europe and Asia display variation in metal tolerance, yet it is unknown whether this is a widespread trait in the genus and whether it occurs in North America. Here we investigate cadmium (Cd) and zinc (Zn) tolerance in S. brevipes and S. tomentosus isolates collected from sites in the Rocky Mountains of Colorado displaying different metal content. In line with previous findings for other Suillus species, we hypothesized (1) S. brevipes and S. tomentosus to display intra-specific metal tolerance variation, (2) Zn and Cd tolerance to be correlated to soil metal content, and (3) tolerant isolates to show lower metal tissue content compared to sensitive isolates (due to increased metal exclusion). We found ample intra- and inter-specific Zn and Cd tolerance variation in both S. brevipes and S. tomentosus, but no correlation between soil metal content and tolerance. There was a negative correlation between tolerance level and Zn uptake, indicating an exclusion-based Zn tolerance strategy. Sensitive and tolerant isolates showed no difference in Cd accumulation, indicating that Cd tolerance in these species is likely not dependent on exclusion. Our study sets the groundwork for further investigation into the genetic basis of Suillus metal tolerance and whether and how it impacts pine mycorrhizal partners.

Mineral and Organic Materials as Factors Reducing the Effect of Petrol on Heavy Metal Content in Soil.

As industrial production increases worldwide, so does the demand for fuels. The transport of fuels from the point of production to the end user poses a risk of environmental pollution, both during transport and during combustion in internal combustion engines. The soil is a part of the environment which is particularly sensitive to contamination by petroleum substances. For this reason, research has been carried out into the possibility of reducing the impact of petrol on the content of heavy metals in the soil using various materials, both mineral (bentonite, calcium oxide) and organic (compost). These played an important role in the in situ remediation of contaminated soils. Petrol contamination increased the content of some heavy metals (Pb, Cd, or Ni), while it decreased the content of other metals (Cr, Zn, Co, and Cu) in the soil. The materials used in this study significantly altered the levels of heavy metals in the soil. The strength of the effect varied and the direction of the effect depended on the element. Bentonite was the most effective, while calcium oxide and especially compost were less effective. The most beneficial (limiting) effect of calcium oxide was shown on the soil content of cadmium, cobalt, and chromium, while the bentonite effects were on the content of chromium. The application of the abovementioned materials seems to be effective in reducing low level soil contamination by petrol.

Heavy Metal Accumulation in Soil and Plants Using Municipal Solid Waste Compost in Variable pH Conditions

ABSTRACT Municipal solid waste composts (MSWC) are extensively utilized as organic soil conditioners and fertilizers in agricultural fields across many countries. However, the use of MSWC can lead to heavy metal pollution in soil and plants, which may adversely affect plant growth. This study examined the impact of MSWC on the heavy metal content in plants and soil across various pH levels. The experiment was conducted in a pot setting with three replications. The research findings indicated that MSWC application increased the levels of copper (Cu) and zinc (Zn) in soils but had no significant effect on lead (Pb), nickel (Ni), manganese (Mn), and iron (Fe) levels. Additionally, increases were observed in the Cu, Zn, and Fe content in plants, while Pb and Ni content remained unchanged. Cu, Zn, and Fe are essential for plant growth, and their enhancement in both soil and plants is a direct result of their relatively high presence in the MSWC used. The soil-plant transfer coefficients show that the transfer of heavy metals from soil to plants is highest under acidic conditions, indicating that the heavy metal content in MSWC can vary depending on soil pH and application rate. Therefore, it is crucial to carefully analyze and evaluate the heavy metal contents of soil and compost samples before employing MSWC in agricultural fields.

Synergistic role of phenylpropanoid biosynthesis and citrate cycle pathways in heavy metal detoxification through secretion of organic acids

Excessive heavy metal contaminants in soils have serious ecological and environmental impacts, and affect plant growth and crop yields. Phytoremediation is an environmentally friendly means of lowering heavy metal concentrations in soils. In this study, we analyzed phenotypic and physiological traits, and the transcriptome and metabolome, of sheepgrass (Leymus chinensis) exposed to cadmium (Cd), lead (Pb), or zinc (Zn). Phenotypic and physiological analysis indicated that sheepgrass had strong tolerance to Cd/Pb/Zn. Transcriptomic analysis revealed that phenylpropanoid biosynthesis and organic acid metabolism were enriched among differentially expressed genes, and metabolomic analysis indicated that the citrate cycle was enriched in response to Cd/Pb/Zn exposure. Genes encoding enzymes involved in the phenylpropanoid and citrate cycle pathways were up-regulated under the Cd/Pb/Zn treatments. Organic acids significantly reduced heavy metal accumulation and improved sheepgrass tolerance of heavy metals. The results suggest that synergistic interaction of the phenylpropanoid and citrate cycle pathways in sheepgrass roots induced organic acid secretion to alleviate heavy metal toxicity. A cascade of enzymes involved in the interacting pathways could be targeted in molecular design breeding to enhance phytoremediation.

MINERALOGICAL AND GEOCHEMICAL PARAMETERS OF SNOW COVER WITHIN THE ANTHROPOGENICALLY DISTURBED SITES OF THE NADYM-PUR INTERFLUVE (NORTHERN PART OF WESTERN SIBERIA)

The article analyzes the content of metals in solid aerosols and snow water sampled in the anthropogeni-cally disturbed and background sites of the Nadym-Pur interfluve. The results of microscopic studies of solid aerosols showed the presence of secondary minerals, technogenic formations, as well as a large amount of pyrite in samples from the eastern part of the study area. The maximum concentrations of metals in solid aero-sols were found in snow of the sanitary protection zones of waste disposal facilities, with the exception of Ca, which prevails in snow cover of Novy Urengoy (up to 10% of dry matter). The urbanized area is characterized by the highest values of dust load (up to 111 mg/m2 a day). The local contamination with Ba within the waste landfills in Novy Urengoy is associated with the sites of barite and drilling waste processing. We applied the factor analysis to identify the main metal associations characteristic of solid aerosols from different functional zones: Ca-Co-V-Mn (city), Ba-Sr-K-Na and Cd-Cu-Pb (waste disposal sites), Cu-Ni-Cd (the entire studied area). Based on the study of the content of dissolved forms in snow water, a high mobility of metals in the northern landscapes and its decrease in urban environment were revealed. The mineralogical and geochemical analysis of snow suggests the influence of the Norilsk industrial region on the eastern part of the Nadym-Pur interfluve, Zn, Cu, Ni, Pb and the mineral pyrite being the indicators. The risks of environmental pollution under the aerotechnogenic transport are associated with high content of Zn, Cu, Ni, Pb and Ba in solid aero-sols. The calculation of the Toxicity Probability Index (MERMQ) showed that some aerosol samples from the landfill sites have a high probability of biological effects. Using data on the chemical composition of soils and soil water, no visible effect of snow pollution on the growth of metal concentrations in soil and soil water was revealed, with the exception of local contamination with Ba, which led to a twofold increase in the content of the metal in the upper soil horizon.

Content of heavy metals in soils of Bidoup Nui Ba National Park (Southern Vietnam)

The study of technogenic pollution of soils with heavy metals (HM) is an essential task for ecology. The analysis of the content of HMs in the park's soils shows the degree of pollution and the sources of its occurrence. The study of the elemental composition of soils is an objective method for assessing the state of the ecosystem. To determine the current state of heavy metal contamination in forest soils, the concentrations of their total forms were analyzed. Heavy metals, including Zn, Pb, Cr, Cu, Hg, Cd, and As, were found in the study area. In addition, the threat of contamination with Cd and As has been identified. The calculation of the total pollution coefficient allows us to assess the level of pollution for the dry season (Zc = 18.45-28.24, average 22.45) as average (moderately hazardous) and for the wet season (Zc = 0.01-5.11, average 1.96) as permissible. This indicates an unfavorable environmental situation. The content of heavy metals in soils depends on the season. Observations show that at the end of the wet season, the concentration of heavy metals decreases, while it increases in the period after the dry season.

Phytoextraction of Some Selected Heavy Metals in Contaminated Soil by Arabian Jasmine (Jasminum sambac)

Heavy metal contamination in soil is a significant environmental and health concern. This study investigates the potential of Arabian jasmine (Jasminum sambac) for phytoremediation of heavy metals in soil. The plants were grown in pots using soil samples collected from contaminated dumpsite soils of Dana Steel Limited in Katsina Metropolis; their ability to accumulate and remove heavy metals was assessed. An atomic absorption spectrophotometer (AAS) was used to measure the concentrations of metals in plants and soil. The statistical analysis of the data obtained was carried out using a t-test. The amounts of the metals under study in the polluted soil before planting were found to be higher than the values from the control soil: Cu (6.49±1.88 mg/kg), Ni (2.67±1.09 mg/kg), Cd (0.20±0.08 mg/kg), Pb (17.57±7.39 mg/kg), Zn (1.63±0.03 mg/kg), and Cr (8.01±2.68 mg/kg). The Bioaccumulation factor for Jasminum sambac was less than one (BAF<1) for all the studied heavy metals: Cu (0.10), Ni (0.32), Cd (0.87), Pb (0.30), Zn (0.02) and Cr (0.30), indicating a low bioaccumulation capacity. However, the transfer factor for Jasminum sambac was greater than 1 (TF>1) in Cu (3.35), Pb (3.00) and Cr (1.97), suggesting that the transfer rate of these heavy metals from soil into the plant's tissues was higher. These findings suggest that using this plant in phytoremediation can be a viable and sustainable approach to reducing heavy metals contamination in soil, thereby offering a potential solution to a significant environmental problem.

Use of Forest Trees in the Treatment of Polluted Soil by Heavy Metals: A Mini Review

Human activities lead to a large accumulation of heavy metals in the soil which comes from industrial activities such as mining smelting refining manufacturing processes and waste resulting from excessive use of chemical fertilizer and vehicle exhausts. So, soil pollutants especially with heavy metals can be treated using different types of plants; such as forest trees and grasses. These plants can tolerate soil pollutants at high concentrations in their biological tissue, and treat pollutants by absorbing and accumulating heavy metals in their living tissues. Therefore, in this article, we reviewed several forest tree species, that showed high resistance in the absorption and accumulation of heavy metals, such as genus Eucalyptus, Acacia, Salix, Populus, Tamarix, Melia, Dalbergia, Leucaena, Acer, Fraxinus, and Thuja. It has been noted that planting forest trees with high biomass that resist high concentrations of heavy metals in soil, works to rid the soil of these pollutants. This is the latest and best technology for treating soil pollution. In particular, it is unique from its counterparts in its environmental friendliness, economic benefits, and other returns resulting from plant cultivation. Therefore, applying phytoremediation techniques that benefit is the best and safest for the environment and living organisms.

Changes in the elemental composition of agrocenosis components on gray forest soil under long-term application of mineral and organic fertilizers

The paper analyzes the elemental composition of soils and plants of agrocenosis on the gray forest soil of Vladimir opolye under long-term application of mineral and organic fertilizers. The content of total and mobile forms of Ni, Cu, Zn, Co, Mn, Fe and the content of these elements in aboveground plant organs, as well as changes in the main agrochemical characteristics that can affect the availability of elements to plants were evaluated. It is shown that the application of mineral fertilizers contributes to soil acidification, increase in the content of organic carbon, mobile forms of phosphorus. At the same time, the variants with joint application of mineral and organic fertilizers are subject to less change of these characteristics, which may be due to the increased buffering capacity of the soil with respect to the components coming with mineral salts, due to the applied organic matter. Introduction of Ni, Cu, Zn, Co, Mn, Fe into agrocenosis with fertilizers (organic and mineral) did not affect the gross content of metals in soil. There was a change in the content of mobile forms of metals in the soil due to changes in agrochemical parameters of soils. Changes in the content of trace elements in plant products were recorded. The reduction of Zn, Cu content in plants on the variants with more intensive use of fertilizers (and with higher yield) is explained by "dilution effect". The low content of Co in the soil and its insufficient supply to the plants must be controlled. The joint use of data on changes in the elemental composition of soils and plants allows better differentiation of experimental variants in the space of principal components when analyzed by this method and is promising for monitoring the consequences of agrogenic load of different degrees. The results obtained can be taken into account in the formation of criteria for assessing the mineral nutrition of plants and fertilizer application rates.

Bismuth Film along with dsDNA-Modified Electrode Surfaces as Promising (bio)Sensors in the Analysis of Heavy Metals in Soils.

Heavy metals constitute pollutants that are particularly common in air, water, and soil. They are present in both urban and rural environments, on land, and in marine ecosystems, where they cause serious environmental problems since they do not degrade easily, remain almost unchanged for long periods, and bioaccumulate. The detection and especially the quantification of metals require a systematic process. Regular monitoring is necessary because of seasonal variations in metal levels. Consequently, there is a significant need for rapid and low-cost metal determination methods. In this study, we compare and analytically validate absorption spectrometry with a sensitive voltammetric method, which uses a bismuth film-plated electrode surface and applies stripping voltammetry. Atomic absorption spectroscopy (AAS) represents a well-established analytical technique, while the applicability of anodic stripping voltammetry (ASV) in complicated sample matrices such as soil samples is currently unknown. This sample-handling challenge is investigated in the present study. The results show that the AAS and ASV methods were satisfactorily correlated and showed that the metal concentration in soils was lower than the limit values but with an increasing trend. Therefore, continuous monitoring of metal levels in the urban complex of a city is necessary and a matter of great importance. The limits of detection of cadmium (Cd) were lower when using the stripping voltammetry (SWASV) graphite furnace technique compared with those obtained with AAS when using the graphite furnace. However, when using flame atomic absorption spectroscopy (flame-AAS), the measurements tended to overestimate the concentration of Cd compared with the values found using SWASV. This highlights the differences in sensitivity and accuracy between these analytical methods for detecting Cd. The SWASV method has the advantage of being cheaper and faster, enabling the simultaneous determination of heavy elements across the range of concentrations that these elements can occur in Mediterranean soils. Additionally, a dsDNA biosensor is suggested for the discrimination of Cu(I) along with Cu(II) based on the oxidation peak of guanine, and adenine residues can be applied in the redox speciation analysis of copper in soil, which represents an issue of great importance.

Geoenvironmetal assessment of different types of cryolithic soils in Western Yakutia under the conditions of diamond-mining operations

The problems of geoenvironmental consequences of mining operations are especially acute in the arctic and subarctic regions, where the spread of permafrost significantly reduces the buffering capacity of landscapes. The article presents data on the content of heavy metals in the soil cover of the transient zone between the middle taiga and north taiga landscapes of Western Yakutia under the conditions of mining operations and assesses the resistance of different types of soils to heavy metals pollution. Field and laboratory works were carried out in August 2022. The heavy metals content was determined by atomic absorption spectrometry. Specialized software was used for analysis, such as MS Excel 2013, Statistica 12.0, and QGis 3.26.1. Calculation of organic forms of heavy metals in soil solutions was performed using the NICA-Donnan model. In the course of studies, the structure of the soil cover in the Nakyn kimberlite field in the conditions of the mining industrial complex operation was determined and a sketch map of the soil cover of the territory was compiled. The geochemical series of the studied heavy metals is as follows according to the degree of concentration of heavy metals in cryolithic soils: Pb > Zn > Ni > Cu > Cd > As > Hg. Positive correlations between humus and Cd, Pb, Zn, as well as the occurrence of synergism in the Pb–Cd, Zn–Pb, Zn–Cu pairs were revealed. The soils organic matter enhances migration of heavy metals. The man-made input of Ni and Zn in cryolithic soils will lead to increase of mobile fraction. Cd is more mobile in pale-yellow carbonate and cryogenic soils. The regional background level of heavy metals for these types of soils was calculated, which can be used in future works when the intensity of mining operations increases.

Ecological problems of technogenic land pollution in the republic of Кazakhstan

A large territory in Kazakhstan is distinguished by the diversity of soils and the complex structure of the soil cover. Soil contamination with heavy metals, especially in the vicinity of large cities and industrial centers, is one of the environmental problems. Of great scientific and practical interest is the determination of the content of heavy metals in soil, their transformation and entry into food and feed. The accumulation of heavy metals in the soil leads to an increase in their concentration in plants, which affects public health. Therefore, the study and identification of areas with high levels of heavy metals in the soil are of increasing importance. The article summarizes the results of a study of soil and vegetation cover in areas adjacent to mining enterprises factories for the production of non-ferrous and rare metals.

Modeling soil moisture from in situ portable X-ray spectrometer measurements: A novel approach for correcting geochemical data across different environments and climatic conditions

The portable X-ray fluorescence (pXRF) spectrometer is widely employed for in situ analysis of both contaminated and uncontaminated soils. However, the accuracy of the measurements can be significantly affected by soil moisture, resulting in unreliable soil pollution monitoring. This effect has already been studied and quantified, but this is ineffective if the soil moisture in the field is unknown. Given the considerable variability of soil moisture conditions across time and space, significant bias during in situ investigations remains a main issue. This study introduces a novel method to estimate soil moisture directly from pXRF field measurements, enabling its reliable use in almost any field condition. The study was conducted using soil samples and in situ pXRF soil surface measurements in Estarreja (Portugal) and Vicdessos (France). In the first experiment, the innovative approach involved modeling soil moisture directly from the raw XRF measurement errors obtained in moist soils using multiple regression. In the second experiment, metal concentrations were modeled as an exponential function of the moisture content. The final model integrates both approaches to correct field data from geochemical mapping in diverse environments, including a coastal region in Portugal and a mountainous region in France. Our findings demonstrate that this simple, efficient and cost-effective method accurately predicts soil moisture (U) using pXRF, as shown by the equation Umeasured = 1.0028 x Uestimated (r2 = 0.9715). The model effectively corrected up to 70% of moisture-induced errors in metal concentrations in the wettest soils and produced more reliable soil Fe, Pb, and Zn maps. Specifically, the accuracy improvement was at least 32% in drier soils (Portugal) and at least 55% in wetter soils (France). This study offers a cost-effective, efficient solution for employing pXRF in geochemical mapping across different climatic conditions and soil environments.

Soil health as a proxy for long-term reclamation success of metal-contaminated mine tailings using lime and biosolids

Mine lands contaminted with heavy metals pose environmental risks, and thus reclamation is paramount for improving soil, plant, animal, and ecosystem health. A metal-contaminated alluvial mine tailing, devoid of vegetation, received 224 ​Mg ​ha−1 of both lime and biosolids in 1998, and long-term reclamation success was quantified in 2019 with respect to soils, plants, and linkages to animals. Reclamation success was quantified using the Soil Management Assessment Framework (SMAF), in conjunction with bioavailable (0.01 ​M CaCl2 extractable) and plant-available (Mehlich-3 extractable) soil metal concentrations, X-ray absorption spectroscopy, plant metal concentrations, and plant quality characteristics. Results showed that all soil indicators were improved in successfully-reclaimed areas as compared to on-site degraded areas, including increases in soil aggregate stability, pH, plant-available P and K, soil organic C, potentially-mineralizable N, microbial biomass C and β-glucosidase activity and decreases in soil bulk density and electrical conductivity. Of indicators, unitless soil health scores were assigned based on the SMAF, with data suggesting that bulk density, wet aggregate stability, potentially- mineralizable N, microbial biomass C, pH, and electrical conductivity should be monitored in the future. The long-term effects of lime and biosolids application have improved soil physical, biological, and overall soil health. Plant metal concentrations have decreased by an order of magnitude since early reclamation, with most plant metal concentrations being tolerable for domestic livestock consumption. From an animal health perspective, feeding grasses from this site during latter parts of a growing season may need supplemental feed to provide greater protein and energy content, and to reduce potentially-harmful Cd concentrations from food chain bioaccumulation. However, a health concern exists based on soil bioavailable Cd and Zn concentrations that exceed ecological soil screening levels. Still, plants have stabilized the soil and acidity remains neutralized, leading to long-term improvements in soil health, with overall improved ecosystem health.

Metal(loid) contamination in Bangladesh: a comprehensive synthesis in different landscapes with ecological and health implications.

Elevated metal(loid) concentrations in soil and foodstuffs is a significant global issue for many densely populated countries like Bangladesh, necessitating reliable estimation for sustainable management. Therefore, a comprehensive data synthesis from the published literature might help to provide a wholistic view of metal(loid) contamination in different areas in Bangladesh. This study provided a clearer view of metal(loid) contamination status and their associated ecological and health risks in different land use and ecosystems in Bangladesh. Comprehensive analyses were performed on data gathered from 143 published articles using multiple statistical techniques including meta-analysis. Considering the potential loading of metal(loid), the data were summarized under various groups, including coastal, rural, urban and industrial regions. Also, the concentrations of seven metal(loid)s, e.g., cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), zinc (Zn), and arsenic (As) in soil, sediment, cereal, vegetable, fruit, surface water and groundwater were included. Results showed that the relative concentrations of metal(loid)s in comparison to the maximum permissible limit (MPL) were mostly less than one, although they varied significantly for locations and individual metal(loid). However, the normalized cumulative relative concentrations over the MPL for all seven metal(loid)s across different environmental samples were 4.75, 2.97, 1.51 and 2.79 for coastal, industrial, rural and urban areas, respectively, which wasdue to the higher concentration of Cd, Cr and Cu. Similar to the metal(loid) concentrations, the average of cumulative median non-cancer risks for all metal(loid)s was in the order of industrial (6.46) > urban (4.05) > rural (3.83) > coastal (2.41). This research outcome will provide a foundation for future research on metal(loid)s and will help in pertinent policy-making by the relevant authorities in Bangladesh.