Concentrations Of Ni In Soil Research Articles

Leveraging visible-near-infrared spectroscopy and machine learning to detect nickel contamination in soil: Addressing class imbalances for environmental management

Excessive concentrations of Ni in soil have many severe effects, negatively affecting human health and leading to disease, while also posing a threat to animals and plants. Although the dangers of high Ni concentrations have been widely recognized, rapid and large-scale tools for the identification of Ni contamination are still lacking. Visible-near-infrared (Vis-NIR) spectroscopy has been employed to rapidly identify Ni contamination; however, previous studies suffer from issues inherent to small datasets and the tendency to negate data imbalances. To address these issues, a large dataset comprising 18,675 soil samples was used to predict soil Ni contamination by combining Vis-NIR data with machine learning (ML). The data imbalance inherent to previous studies was addressed using two data sampling methods. To build a robust classification model for Ni contamination, four spectral preprocessing methods and four ML algorithms were compared. The optimal extreme gradient boosting model achieved recall, accuracy, area under the curve, and geometric mean scores of 0.8203, 0.8806, 0.9268, and 0.8508, respectively. Model predictions across the United States identified specific regions with high possibility of Ni contamination. Overall, the model developed in this study offers an improved accuracy in predicting soil Ni contamination at the continental scale, and can be used to prioritize further testing and guide policymaking.

Toxicity factors, ecological and health risk assessments of heavy metal in the urban soil: a case study of an agro-machinery area in a developing country.

The contribution of heavy metals in surface soils by the influences of agro-machinery factories is a significant growing concern. Heavy metals were analyzed by inductively coupled plasma mass spectrometry technique to assess human and ecological risks. The concentrations of Fe, Cd, Cr, Cu, As, Pb, Mn, Ni, and Zn in soil ranged from 18,274-22,652, 2.06-4.92, 24.8-41.9, 126.8-137.5, 9.20-25.2, 17.8-46.1, 114.4-183.1, 86.9-118.1, and 101.6-159.6mg/kg, respectively. The enrichment factor values of heavy metals were greater than 1.5, suggesting severe anthropogenic activities such as untreated waste discharging, burning of metallic wastes, wear, and tear, and dismantling of old batteries for heavy metals enrichment in studied soil. The contamination factor indicates considerable to very high contamination of heavy metals in soil. Moderate to high ecological risk was observed for analyzed metals which mainly originated from the maintenance and repairing of various engines in the workshop and welding and soldering of metallic substances. The target hazard quotient (THQ) was ranged from 6.99E-04 to 2.21E-01 for adults and 5.59E-03 to 1.82E + 00 for children, respectively; indicating children were more sensitive to heavy metals exposure from soil dust. The carcinogenic risk of As (1.72E-05) exceeded the USEPA acceptable limits indicating cancer risk to the residence. The current emphasized the significance of intensive heavy metals monitoring in surface soils around the agro-machinery areas due to their potential health risks associated with children.

Съдържание на микроелементи (Mn, Zn, Cu, Pb, Ni и Cd) в почвата и ориенталски тютюн след продължително минерално торене

The effect of long-term mineral fertilization with different N, P and K rates on the concentration of Mn, Zn, Cu, Pb, Ni and Cd in soil and oriental tobacco (monoculture) was studied in 50-years stationary trail. Studies were conducted in 2014-2016 on rendzina soil at the Tobacco and Tobacco Products Institute - Markovo. The concentrations of total micronutrients in soil showed relatively small variation and they were not largely influenced by long-term mineral fertilization with different N, P and K rates. The accumulation of available Zn, Cu, Pb and Cd in the soil was also not significantly influenced by mineral fertilization. Available Mn and Ni were higher in fertilized treatments compared to unfertilized control. The long-term fertilization had no significant effect on Mn, Pb and Ni concentration in tobacco leaves. For lower and middle leaves, 225 kg P2 O5 ha-1 treatment resulted in lowest Zn concentration. The content of copper and cadmium in the leaves tended to decrease in mineral fertilizer treatments compared to the unfertilized control. When oriental tobacco was grown on rendzina soil with good buffering capacity, the risk of Mn, Zn, Cu, Pb, Ni and Cd accumulation in tobacco leaves associated with long-term mineral fertilization is low. These experimental conditions are adequate for the production of high quality sun-cured leaves with a low level of nicotine content, higher in reducing sugars and moderate in total nitrogen.

WITHDRAWN: Trace metals translocation from soil to plants: Health risk assessment via consumption of vegetables in the urban sprawl of a developing country

The study was conducted at 15 locations around the thermal power plant of Patuakhali district at the coastal area of Bangladesh to determine trace elements in vegetable and assess risk of toxicity. Eight vegetables, namely, tomato (Solanum lycopersicum L.), radish (Raphanus raphanistrum L.), bean (Phaseolus vulgaris L.), brinjal (Solanum melongena L.), bottle gourd (Lagenaria siceraria L.), red amaranth (Amaranthus cruentus L.), arum (Arum maculatum L.) and lady's finger (Abelmoschus esculentus L.) were analyzed for nine trace metals (Cr, Ni, Cu, As, Cd, Pb, Fe, Mn and Zn) to assess contamination load of trace elements in agricultural soil, and health risks posed from vegetable consumption. The mean concentrations of Cr, Cr, Ni, Cu, As, Cd, Pb, Fe, Mn, and Zn in soil were 16.6, 14.8, 5.8, 1.3, 0.72, 9.7, 55261, 456.1, and 105.8 mg/kg, respectively. Average concentrations of As, Cd, and Pb in vegetable species were higher than the maximum allowable concentration (MAC), indicating vegetables species were contaminated by these elements and may pose potential risk to human. Fe, Mn, Zn, Cr, Cu, Pb, and As in soil and vegetables of the study area may arise from anthropogenic activities. The present study suggests that surface soil used for vegetables production should be continuously monitored to check the transfer of toxic metals into the vegetables to minimize the adverse health impacts on consumers and potential threats to food safety.

Characterization of soil trace metal pollution, source identification, and health risk assessment in the middle reaches of the Guihe River Basin.

The natural environment, as well as human production and survival, is intrinsically dependent on soil. This study comprehensively assessed the pollution status, health risks, and sources of trace metals in the middle reaches of the River Gui Basin (MRGB) utilizing the geoaccumulation index, potential ecological risk index (PERI), and human health risk evaluation method. The findings of this study provide the following key insights: (1) only Cu and Pb levels in the MRGB soils did not exceed the background values established for soils in Weifang City (WFC). (2) The geoaccumulation status in most areas of the MRGB ranged from non-polluted to mildly polluted, with the overall ecological risk classification ranging from mild to moderate. (3) The cumulative non-carcinogenic risk for humans in the MRGB remained within acceptable limits, whereas the carcinogenic risk indices fell within tolerable levels. Oral ingestion emerged as the primary exposure pathway for both non-carcinogenic and carcinogenic health risks. (4) Cu, Zn, Ni, and Cr concentrations in MRGB soils primarily stemmed from natural sources associated with parent rocks, with Zn exhibiting additional influence from anthropogenic factors. In contrast, Pb, Cd, Hg, and As concentrations were predominantly driven by anthropogenic sources. Although the soils in the MRGB typically exhibited mild-to-moderate contamination levels, the contamination levels of Hg and Cd were notably more severe. As and Cr were significant health hazards. Most soil contamination sources are attributed to anthropogenic factors, warranting heightened attention from the relevant authorities.

Phytoremediation technology for recovery of Ni by Acacia plants in association with Bacillus amyloliquefaciens isolated from E-waste contaminated site

Electronic waste (e-waste) illegally disposal in Thailand is becoming more widespread. A sustainable metal recovery technology is needed. A phytotechnology called “phytomining” of metals such as nickel (Ni) is a promising technology providing a sustainable solution to the growing e-waste problems. This study investigated the ability of Acacia species in association with e-waste site isolated, plant growth-promoting rhizobacteria (PGPR), Bacillus amyloliquefaciens. Acacia mangium accumulated higher Ni in their tissues when Ni concentrations in soil were lower than 200 mg kg−1. The inoculation of PGPR B. amyloliquefaciens enhanced Ni uptake and accumulation in the leaves, stem, and root. The results showed that the highest Ni concentration was found in the root ash (825.50 mg kg−1) when inoculated plants were grown in soil containing 600 mg kg−1 Ni. Hence, the Ni recovery process and mass balance were performed on root ashes. The highest Ni recovery was 91.3% from the acid (H2SO4) leachate of the ash of inoculated plant treated with 600 mg kg−1 Ni. This demonstrates the feasibility of PGPR-assisted phytomining from Ni-contaminated soil. Phytomining of Ni from any e-waste contaminated sites using Acacia mangium in combination with B. amyloliquefaciens can promote plant growth and improve the uptake of Ni.

Spatial distribution of heavy metals, source identification, risk assessment and particulate matter in the M4 motorway.

Metal-containing dust is a potential severe environmental and human health threat. Metals present in dust may originate from car exhausts, tear and wear of tires, and vehicular emissions, which are less manageable. Metal-containing dust from roads can contaminate the soils, and crops alongside motorway. This study aimed to investigate the Pb Cd, Cu, Ni, and Zn concentrations in dust, soil, and vegetation collected from the M4 motorway Faisalabad. The results indicated that average metal concentrations in dust from all sites varies (Pb) 44.01mgkg-1, (Cd) 1.22mgkg-1, (Cu) 49.5mgkg-1, (Ni) 28.3mgkg-1, and (Zn) 113.7mgkg-1. The pollution assessment indices CF and PLI of Industrial city and Painsra had comparatively maximum levels of environmental pollution. Moreover, the geo-accumulation index (Igeo) of metals was high at Chak 115 and Painsra, while Igeo at ten sites was in the following descending order: Cd > Pb > Cu > Ni > Zn. Furthermore, it was identified that the maximum ecological risk index (Eir) was in declining order, i.e., Cd > Pb > Cu > Ni > Zn, at all sites. The potential ecological risk was categorized as high risk in all respective sites. The particulate matter fractions PM2.5 and PM10 represented the maximum risk at the Industrial city site, which was unhealthy, although the Painsra site had poor air quality. The total suspended particulate was classified as hazardous at FDA city and Painsra. In contrast, food crops (maize, sugar cane, and sesame) and soil along the M4 motorway have similar Pb, Cd, Cu, Ni, and Zn contamination patterns like dust. However, two crops, maize and sugarcane, along the M4 motorway were found to be more polluted. The level of metals contamination through dust disposition was consistently higher adjacent to roads, possibly indicating depraved impacts on food crops.

Assessment of trace elements in the long-term banana cultivation field’s soil

This work assesses the contamination of trace elements (Cr, Cu, Ni, As, Zn Cd, Mn, Fe, and Pb) in soil and different tissues of the banana plant (Musa spp.), the ecological risks of trace elements using various indices, and the probable health risks using a chemometric approach. Soil and different banana plant tissues were collected from banana fields around the industrial area of the capital of old Pundranagar (the earliest urban archaeological location), Bangladesh. Samples were digested by acid digestion, and trace elements were measured by inductively coupled plasma spectrophotometer (ICP-MS). The concentrations of Cr, Ni, Cu, As, Cd, Pb, Fe, Mn, and Zn in soil ranged from 1.50–61.7, 2.42–87.4, 2.00–100.8, 0.25–31.2, 0.10–12.7, 0.60–91.8, 11330–23782, 8.69–105.9, and 7.50–125.9 mg/kg, respectively. The mean concentrations of trace elements in four tissues descend in order of roots > leaves > stems > fruits. The abundances of trace elements varied in both soil and plant samples, which apparently occurred due to the variations of soil parent materials and the excessive use of agrochemicals for long-term banana cultivation. The soil exhibited a moderate to high degree of contamination with trace elements, and Cr, Pb, Zn, Cd, and As mainly originated from anthropogenic sources. Both non-cancer and cancer risks were perceived due to Cr and As exposure from the fruit tissue of banana plants in the study area.

Distribution characteristics, risk assessment, and relevance with surrounding soil of heavy metals in coking solid wastes from coking plants in Shanxi, China.

Heavy metal concentrations represent important pollution evaluation indices, and it is necessary to assess the potential environmental and health risks from heavy metals associated with coking wastes from coking plants. In this study, coking sludge (CS), tar residue (TR), coke powder (CP), and sulfur paste (SP) from three coking plants (Plant A, Plant B, and Plant C) in central, western, and southern Shanxi Province and from soils surrounding Plant A were selected as the research objects, and the distributions of Cu, Ni, Pb, Zn, Mn, Cd, and Cr were determined. The results showed that Cd in the four solid wastes far exceeded the soil background value by a factor of 16~195, and the contents of Pb in TR (three plants) and CS (Plant C) exceeded the soil background values 19.70-, 23.57-, 14.46-, and 12.56-fold, respectively. Similarly, the concentrations of Cu, Ni, Pb, Zn, and Cd in soils were higher than the background values by factors of 31.18, 8.35, 34.79, 29.48, and 3.43, respectively. In addition, the Cu, Ni, Pb, and Cr in the four solid wastes and soils mainly existed in the residual state. As depth increased, the overall Ni, Pb, Mn, and Cd concentrations in soils increased. The high ecological risks associated with the four solid wastes were mainly due to the enrichment of Cd. Workers in coking plants face certain Cr health risks. This study provides theoretical support for the coking industry with respect to the treatment, disposal, and management of solid wastes.

Stabilization of Ni by rhamnolipid modified nano zero-valent iron in soil: Effect of simulated acid rain and microbial response

Nickel (Ni), as one of the essential micronutrients, exists widely in nature, but high concentration of Ni in soil can pose certain biological toxicity. Nano zero-valent iron (nZVI) and rhamnolipid modified nZVI (RL@nZVI) can effectively stabilize Ni in soil. In this study, the stabilization effect of nZVI and RL@nZVI on the Ni-polluted soil under simulated acid rain and the microbial community response during the soil remediation under different Ni levels (200, 600, and 1800 mg/kg) were investigated. The results show that the addition of nZVI and RL@nZVI increased the pH of leachate to neutral and decreased the amount of Ni in leachate (23.33%–47.06% by nZVI and 50.01%–70.47% by RL@nZVI), indicating that nZVI and RL@nZVI could reduce the potential radial migration risk of Ni in soil under simulated acid rain. The addition of RL@nZVI was beneficial to recover the soil bacterial community diversity, which was inhibited by Ni pollution, and rhamnolipid coating could reduce the toxicity of nZVI. The dominant bacteria in RL@nZVI-treated soil with low, medium, and high Ni pollution were Firmicutes, Proteobacteria and Actinobacteria, respectively. Soil potential, total organic carbon, and pH were the main driving factors affecting the bacterial community structure, while Ni stress only caused changes in the relative abundance of some tolerant bacteria.

Translocation, Accumulation, and Comprehensive Risk Assessment of Heavy Metals in Soil-Crop Systems in an Old Industrial City, Shizuishan, Ningxia, Northwest China

In order to explore the environmental geochemistry characteristics of heavy metals (HMs) in soil-crop systems in an old industrial city, the concentration and fraction of HMs in the paddy, wheat, and maize root soil and their seeds were detected and analyzed. Subsequently, statistical methods, risk assessment coding (RAC), the bio-enrichment coefficient factor (BCF), influence index of comprehensive quality (IICQ), and ArcGIS spatial interpolation were used to conduct the translocation, accumulation, and comprehensive risk assessment of HMs in soil-crop systems. The results showed that the average concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in root soil were ranked respectively as follows:12.56, 0.19, 63.48, 23.52, 0.038, 28.86, 21.68, and 69.47 mg·kg-1. HMs in root soil were accumulated to some extent in comparison with the soil background value in Ningxia, especially Cd and Hg, but did not exceed the soil environmental pollution screening value (GB 14618-2018). The average concentrations of the eight aforementioned elements in supporting crop seeds were 0.0149, 0.0112, 0.075, 6.7, 0.0015, 0.67, 0.0427, and 20.48 mg·kg-1 in turn. The over-limit ratio of As, Pb, and Cr in crop seeds was 4%, 3%, and 1%, respectively, relative to the national food safety standards (GB 2762-2017), whereas the other five elements were within the allowable range. In comparison to those in paddy and wheat, HMs hardly tended to translocate to maize seeds from root soil. According to the results of IICQ in soil-crop systems, the cultivated soil was in the state of slight sub-contamination regionally, and only 10% of sampling points showed slight (sub-)contamination-submoderate contamination, where we could replant maize to reduce HMs contamination risk.

TRANSFER OF HEAVY METALS IN SOIL IN-PLUM CULTIVATION: A FIELD STUDY IN ADAMACHI IASI, ROMANIA

Currently, global environmental concerns about heavy metal pollution are driven by rapid urbanization and industrial development. Therefore, a field study was conducted to assess the concentration of heavy metals (Pb, Co, Zn, Ni and Cu) in orchard soils and its transfer to two plum varieties (Stanley and Anna Späth) at Adamachi Farm – Iasi University of Life Sciences (IULS). In addition, heavy metal transfer (MTF), daily metals intake (DIM) and the index of health risk (HRI) were evaluated. The concentration of Pb, Co, Zn, Ni and Cu in soil and plum leaves samples were analyzed using atomic absorption spectrometry after acid digestion with a mixture of HNO3 (65%), HCl (37%) and HClO4 (60%). Metal concentration patterns occurred as follows 130.65>76.6>30.36> 21.69>13.26 mg/kg for Cu, Zn, Ni, Pb and Co in soil samples and 20.16>10.00> 2.10>1.68 mg/kg for Zn, Cu, Ni and Pb in plum leaves, while Co residue was not detected. The maximum heavy metal concentrations were found at the soil surface (0 – 30 cm depth) due to soil organo-mineral content and antifungal treatments. The health risk index predicted (HRI) for adults as well as children was in the sequence Pb > Cu > Ni > Zn, suggesting no health risk with values that did not exceed the safe limit (1). Therefore, it is essential to manage the causes and sources of heavy metal transfer prudently and effectively in order to prevent environmental contamination.

ACCUMULATION OF HEAVY METALS IN CELERY PLANT APIUM GRAVEOLENS AND SOIL IRRIGATED WITH WASTEWATER WITHIN DUHOK CITY KURDISTAN OF IRAQ

Wastewater contains poisonous metals which can be moved and accumulated in plants before entering the human body through the food chain. The aim of this research was to investigate the concentrations of toxic metals such as Nickel (Ni), lead (Pb), and copper (Cu) in wastewater, celery plant and farmlands soils of Duhok city Kurdistan of, Iraq. The heavy metals accumulation in the Celery plants, soil and water samples were analyzed by using an atomic absorption spectrophotometer. The results obtained showed that the mean concentrations of Pb, Ni, and Cu in the wastewater and Celery plants samples ranged from 0.45±0.08 to 5.95±0.2, 0.18±0.01 to 1.95±0.28, 0.02± 0.01 to1.13±0.23 mg/L respectively. The pattern of metal buildup in wastewater-irrigated soil is in the order: Cu > Pb > Ni, and the mean concentration of Pb, Ni and Cu in soil ranged between 21.68±0.42 to 118.57±0.07, 1.27±0.47 to 5.70±0.23, 1.28±0.24 to ± 15.12 0.53 mg/kg-1, respectively. While the mean concentration of Pb, Ni and Cu in celery leaves ranged from 1.04±0.22 to 5.22±0.60, 0.52± 0.22 to 4.31± 0.12, respectively. 1.34 ±0.22 to 19.47±0.82, 1.23±0.04 to 7.29± 2.53, 1.01±0.05 to 5.76±1.32 mg/ kg-1, respectively. According to this study, roots contain more heavy metals than leaves. According to the findings, a few of the sampling sites had Pb, Ni, and Cu values that were exceeded the permissible concentration. Celery plants cannot be planted in the Duhok Valley to prevent excessive heavy metal exposure to human health through vegetables, where the main irrigated water source is sewage from the local municipalities. Celery plant irrigation with wastewater has much greater levels of heavy metals than the controls.

Composition of some trace elements in wheat plant and soil

Zinc, copper, nickel, and manganese are essential nutrients for plants. However, excessive accumulation in the plant can lead to significant risks and problems in terms of human health after consumption. Also, the accumulation of chromium, cadmium and lead elements in plants can have a toxic effect on human health. This study aimed to determine the concentrations of copper (Cu), chromium (Cr), cadmium (Cd), nickel (Ni), manganese (Mn), zinc (Zn), and lead (Pb) trace elements in wheat plants and soil. Mean trace element levels in soil samples taken from the city center Mn 556.9 mg kg-1, Ni 62.45 mg kg-1, Cr 24.98 mg kg-1, Zn 40.75 mg kg-1, Cu 17.25 mg kg-1, Pb 7.65 mg kg-1, Cd as 1.63 mg kg-1 and the average trace element levels in soil samples taken from villages Mn 418.7 mg kg-1, Zn 48.53 mg kg-1, Ni 32.34 mg kg-1, Cu 15.93 mg kg-1, Cr 13.7 mg kg-1, Cd 1.033 mg kg-1 was determined. Cd, Cr, and Pb concentrations were not detected in wheat samples. Average Cu (4.462 mg kg-1), Mn (30.03 mg kg-1), and Zn (20.39 mg kg-1) concentrations in wheat samples were determined at lower levels compared to soil samples. In the process of transporting trace elements from the soil to the plant, even if the plants are grown under the same conditions, the trace element levels accumulated in the plant may differ.

Characteristics of Soil Heavy Metal Pollution and Health Risk Assessment in Urban Parks at a Megacity of Central China

In this study, we compared the concentrations of the heavy metals Cd, Cr, Cu, Zn, Ni, and Pb in the surface soils of urban parks in Wuhan, Hubei Province, with those in the surface soils of urban parks worldwide. The soil contamination data were assessed using enrichment factors and spatial analysis of heavy metals using inverse distance weighting and quantitative analysis of heavy metal sources with a positive definite matrix factor (PMF) receptor model. Further, a probabilistic health risk assessment of children and adults using Monte Carlo simulation was performed. The average Cd, Cr, Cu, Zn, Ni, and Pb concentrations in the surface soils of urban parks were 2.52, 58.74, 31.39, 186.28, 27.00, and 34.89 mg·kg-1, respectively, which exceeded the average soil background values in Hubei. From the inverse distance spatial interpolation map, heavy metal contamination was primarily observed to be present to the southwest of the main urban area. The PMF model resolved four sources: mixed traffic and industrial emission, natural, agricultural, and traffic sources, with relative contributions of 23.9%, 19.3%, 23.4%, and 33.4%, respectively. The Monte Carlo health risk evaluation model demonstrated negligible noncancer risks for both adult and child populations, whereas the health effects of Cd and Cr on children were a concern for cancer risks.

Performance of castor in heavy metal polluted soils under the treatment of various decontaminants

In order to find out the performance of castor under decontaminant treated heavy metal polluted soils, an experiment was conducted at Students Farm, College of Agriculture, PJTSAU, Rajendranagar, Hyderabad, during kharif 2016 to study the performance of castor in heavy metal polluted soil under the treatments of various decontaminants (various dosages of phosphorus as well as, quick lime). The dry matter before flowering, and stalk yield at harvest of castor varied from 429 to 516, 1460 to 1758 kg/ha, respectively. Among the different decontaminants highest dry matter yield and stalk yield (516 and 1758 kg/ha at before flowering and harvest) and seed yield (1720 kg/ha) was obtained in T5 (RDF+CaO @ 2 t/ha), which was significantly superior over all other treatments and on par with T4 (RDF+CaO @ 1 t/ha), and per cent increase over RDF was 20.41 and 23.56, respectively for stalk, and seed yield of castor. Decontamination treatments had reduced the mean Pb, Cd, Ni and Co contents of castor to 4.51, 0.65, 0.95 and 0.63 mg/kg, and increased mean uptake to 7.62, 1.17, 1.69 and1.09 g/ha respectively, for Pb, Cd, Ni and Co in seed at harvest. The Pb, Cd, Ni and Co contents of soil after harvest of the castor crop ranged from 17.11, 0.79, 1.89 and 1.22 mg/kg in the reference control and decreased to 14.60, 0.68, 1.67 and1.02 with RDF+CaO @ 2 t/ha treatment. The reduction in Pb, Cd, Ni and Co concentration in post-harvest soil was more due to Cao at different levels when compared to high phosphorus.

The depth of the soil's horizons profile has an effect on the human health impact score

The chemical composition of soils reflects the degree of industrial exposure. Cu and Ni concentrations in soils of the «Severonickel » plant vicinity are higher than remote ones. In the impact area, the mean concentration of the heavy metals in the subsoils is 55 [ppm] for Ni and 33 [ppm] for Cu. Soils’ chemical composition varies over different mineral horizons. The subsoil layer is the main accumulator of chemical elements, including pollutants. Erosion of the surface layer and technogenic disturbance of the soil profile can lead to subsoil spreading and a significant increase in the human health Impact Score. At the same time, the default IS calculation is focused on the 0.1 [m] depth for all zones. In the paper two factors are considered in the impact modeling modification. The human health Impact Score is calculated specifically for each genetic soil layer with the respective depth of the profile (from 0.05 [m] to 0.2 [m]) and for soils from background and impact areas. The discrepancies between default and modified Impact Scores are observed. In the Impact area, the highest IShum for Ni is 60, for Cu is 5.6 [DALY]; in the Background area, it is 11 and 3.1 [DALY] respectively. The importance of using the regionally modified values in population health impact monitoring is highlighted.

Coupled retrieval of heavy metal nickel concentration in agricultural soil from spaceborne hyperspectral imagery

Widespread soil contamination endangers public health and undermines global attempts to achieve the United Nations Sustainable Development Goals. Due to the lack of relevant studies and low precision of spaceborne spectroscopy, estimating soil heavy metal concentrations is challenging. In this study, we developed a coupled retrieval to qualify the heavy metal nickel (Ni) concentration in agricultural soil from spaceborne hyperspectral imagery. The retrieval couples spectral feature extraction from multi-scale discrete wavelet transform (DWT) and dimension reduction (DR), optimal band combination algorithm to five machine learning retrieval models using tree-based ensemble learning, neural network-based, and kernel-based. The comparison between the retrievals and Ni measurements shows that the DWT combined with t-distributed stochastic neighbor embedding (tSNE) coupled extreme gradient boosting (XGboost) retrieval model exhibited the best prediction for the validation dataset. Moreover, due to the integration of six statistical indicators of model performance and the fitted slope of the regression line, the retrieval framework can produce more robust and accurate predictions than those that rely on correlation coefficients. The demonstrated potential of spaceborne hyperspectral remote sensing to provide accurate quantitative measurements of soil heavy metal concentrations will serve as a reference for agricultural plot applications worldwide.

Morupule fly ash as amendments in agricultural soil in Central Botswana

The potential of Morupule fly ash as a soil amendment was evaluated using spinach and rape vegetables planted successively in Palapye soils added with 0 fly ash (FA), 5% FA, 10% FA, and 15% FA (w/w) in combination with four nutrient sources as no fertilizer (-NF), compost (+COMP) at 20 tones ha −1 , inorganic NPK (+NPK) and a combination of 1 2 NPK and 1 2 compost (+NPK+COMP). Spinach was grown first for 40 days followed by rape as a second crop planted on the same pots and treatments after harvesting spinach. The application of FA increased the pH, EC, and the total concentration of As, Cu, and Pb of soil while compost increased the total Zn. The available concentration of Cr, Cu, Mn, Ni, and Pb were significantly reduced by FA. FA increased the yield of spinach and rape, especially in 10FA+NPK+COMP. The heavy metal concentration in the shoots of spinach and rape were below the maximum acceptable limits (MAL) for vegetables in 10FA+NPK and 10FA+NPK+COMP treatments. Overall, an application rate of 10% FA combined with compost and fertilization gave the highest yield and safe level of As, Cr, Cu, Mn, Ni, Pb, and Zn in the edible shoots. • First report on using Morupule fly ash as an amendment in agricultural soils in Botswana. • A combined with compost and inorganic fertilizer improved the growth and yield of spinach and rape grown successively. • Fly ash amendments reduced the available concentration of Cr, Cu, Mn, Ni, and Pb in soil. • Fly ash at 10% application combined with compost and inorganic fertilizer produced spinach and rape safe for human consumption.

Distribution Characteristics and Risk Assessment of Heavy Metal Pollution in Farmland Soils and Crops in Luancheng, Shijiazhuang City

In order to explore the distribution characteristics of heavy metal contamination of farmland soil surrounding Luancheng town, Shijiazhuang City, Henan province, the concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the surface soil and crops were determined and assessed. The principal components were also analyzed for source apportionment. The heavy metal concentrations in crops were further detected, and the non-carcinogenic health risks in the study area were evaluated using the probabilistic risk assessment method, as to provide a theoretical basis for the treatment, prevention, and control of heavy metal pollution in farmland soil in Luancheng. According to the results, ω(Cd), ω(Cr), ω(Cu), ω(Pb), and ω(Zn) in the soils were 0.06-1.08, 22.14-473.47, 12.83-150.74, 10.75-577.72, and 62.23-652.78 mg·kg-1, which exceeded the standard with over-standard rates reaching 1.83%, 1.22%, 0.61%, 0.61%, and 1.22%, respectively. Further, Cd and Pb were transported into crops, in which Cd concentrations exceeded the standard in some corn samples, and Cd and Pb concentrations exceeded the standard in some wheat samples. The total non-carcinogenic health risks (TTHQ) to the human body caused by the consumption of heavy metals in corn grown in the study area were all less than 1, with no obvious negative effects, and TTHQ was higher than 1 in wheat, increasing the likelihood of negative impacts on the human body. With the influence of the distribution of pollution-related enterprises in the industrial zone, heavy metal concentrations were higher in the south, west, and middle directions of the study area. Among them, the study area soil was slightly contaminated by Cd (Level 1). Cd and Hg had a slight potential ecological risk (Level 2), whereas other heavy metals had low potential ecological risk (Level 1). In general, most of the surface cultivated soil was not obviously polluted by heavy metals in the study area. According to the PMF results and survey, we speculated that soil heavy metals mainly came from soil parent material (52.05%), artificial pollution sources (historical sewage irrigation and industrial manufacture) (32.98%), and atmospheric deposition (14.97%). To summarize, the study area should be divided into a priority protection category and safe utilization category. The input of pollution sources should be strictly controlled for the priority protection category, and alternative planting, rotating, and fallow should be implemented for the safe utilization category to reduce the risk of standard-exceeding agricultural products.