Contamination Of Agricultural Land Research Articles

Sustainable Approaches used in Pesticides contaminated Agricultural Waste Water Remediation

With the growing population of our global community and thereby increasing the demand for food has led the farmers to use more and more pesticides. Pesticides are chemical compounds used to kill pests. It is commonly used to control various agricultural pests that destroy crops and ultimately affect our agricultural productivity. Although the use of pesticides is a beneficial approach, but unfortunately it also has some drawbacks in terms of harming the environment and human health. Some pesticides pose significant hazards that ultimately affect human health systems. Contamination of agricultural land and agricultural wastewater by pesticides is a serious environmental problem and has a negative impact on biodiversity. Most synthetic pesticides are not readily biodegradable, they accumulate in the environment and cause soil contamination. To overcome the environmental burden of pesticide-contaminated sites, various sustainable approaches can be effectively used to detoxify contaminants or transform them into harmless secondary compounds. The current review focuses on the role of microorganisms and lignocellulosic biomass and plants in the degradation of agricultural pesticides under sustainable approaches.

Efficient removal of lead from polluted paddy soil by one-pot synthesized Nano-Fe3O4 incorporated stable lignin hydrogel

Lead (Pb) contamination in agricultural soils poses a significant threat to both ecosystems and human health. While nano-Fe3O4 exhibits promising potential for Pb remediation, its practical application in the soil is hindered by its’ biotoxicity, easy aggregation, and the risk of secondary pollution. Thus, this study presents a novel approach wherein Fe3O4 was incorporated into hydrogel via a one-pot synthetic strategy (Fe3O4@LH). This incorporation enhanced the mechanical properties and environmental stability of the hydrogel composites. Based on the mechanical properties, environmental stability, and single-point adsorption results for Pb, we selected Fe3O4@LH-4 for further research. The removal mechanism and the feasibility of employing Fe3O4@LH-4 for Pb removal from paddy soil were investigated through batch adsorption experiments and soil culture studies. Results showed that the adsorption process was primarily governed by swelling adsorption, electrostatic adsorption, ion exchange, precipitation, nanometer effect, and complexation mechanisms. The application of Fe3O4@LH-4 significantly led to the reduction of 16.7 %–25.4 % in soil Pb content, with removal rates escalating alongside increased dosage and application periods of Fe3O4@LH-4. Fitting results of the prediction model indicated that the Pb content in mildly Pb-contaminated soil (186.55 mg/kg) would decrease to be below the risk control standard for soil contamination of agricultural land in China (140 mg/kg) after 112 days of continuous application. Concurrently, cadmium and arsenic contents in the soil decreased by 5.2 %–10.8 % and 7.1 %–16.7 %, respectively. Moreover, the application of Fe3O4@LH-4 positively influenced soil nutrient levels, with total nitrogen and soil organic matter content significant increments of 13.6 %–41.0 % and 4.6 %–16.1 %, respectively. Furthermore, Fe3O4@LH-4 recovery exceeded 88.3 % after a 90-day application period. These findings underscore the potential of Fe3O4 incorporated hydrogel as a promising agent for the sustained removal of heavy metal Pb from paddy soil.

Побудова картосхем щільності забруднення 137Cs сільськогосподарських угідь за сукупністю результатів обстеження

A methodology for mapping the density of 137Cs contamination of agricultural land is proposed and tested. The methodology is based on data on gamma-dose rate measurements, gamma-logging results, and direct determination of 137Cs in soil samples, which were obtained by different organizations in different years. It allows to generalize all available information on 137Cs contamination of the lands and significantly improves the representativeness of estimates of the spatial distribution of the radionuclides at the mapping.

Ukraine – environmental aspects of humanitarian demining

In 2021, Ukraine produced such an amount of food that it would have been possible to feed about 400 million people, not counting the population of Ukraine. The strategy for the development of the agricultural sector of Ukraine envisages providing food for 1 billion of the world’s population by 2030. However, the aggression of Russia on February 24, 2022, and the subsequent hostilities led to the contamination of agricultural lands with a significant amount of Explosive Remnants of War (ERW), which requires humanitarian demining. This article is devoted to the review of the humanitarian demining process from the point of view of its impact on the environment and the determination of the main components affecting the production of agricultural products. In the first period of the demining process, there will be a significant decline in the production of agricultural products. This decline will be determined by the reduction in the area of cultivated agricultural land due to the danger of explosion. In the course of the demining and liquidation of ERW, the area of land will increase, as will the volume of production, but the quality of products will decrease due to the presence of heavy metal compounds and explosive residues in it and the deterioration of the quality of the soil itself. Therefore, after the liberation of Ukraine’s territory, contaminated by mines and ERW, taking into account its importance as the world’s granary, the demining time is of great importance and Ukraine will be very grateful for any help that will reduce it.

Assessment of degradation transformations of agricultural lands

The use of soil for the production of crop products leads to changes in the natural properties of soils and their natural state. When various situations arise, soil properties can change in different forms and with unequal degrees of severity; a process that worsens quantitative and qualitative properties is defined as soil degradation. The significant role of soil in people’s lives should serve as an incentive for its rational use and to prevent the occurrence of degradation transformations leading to a decrease in its environmental and production functions. The purpose of the research is to assess soil contamination of agricultural lands in the Samara region with insecto-acaricides and herbicides. Objectives: - to establish the average and maximum content of residual quantities of pesticides in soils; - determine the area of contamination with residual quantities of pesticides. The research was carried out in 7 districts (Bezenchuksky, Syzransky, Stavropolsky, Volzhsky, Privolzhsky, Bolshechernigovsky, Elkhovsky) of the Samara region in 2020-2022. To assess soil contamination with residual amounts of pesticides, soil samples were taken in spring and autumn to the depth of the arable layer. In selected soil samples, the residual amount of insectoacaricides (DDT, HCH, HCB, metaphos) and herbicides (prometrin, atrazine, simazine, 2.4-D, trifluralin, THAN, dalapon) was determined. The analysis of contamination of agricultural land in the study region showed that the content of controlled pesticides in soils depended on both the period of soil sampling and the year of research.

Assessment of Zn, Pb and Cd in Soil around an MSW Incineration Plant: Using Risk Assessment and Multivariate Statistical Techniques

To investigate and evaluate the spatial distribution of Zn, Pb and Cd in the soil around a municipal solid waste incineration plant and its ecological risks, Zn, Pb and Cd were analyzed in soil samples around a municipal solid waste incineration plant in Chengdu, Sichuan Province, China. The results revealed that the average content of Zn and Pb did not exceed the soil environmental quality value for the risk control standard for soil contamination of agricultural land (GB15618-2018), but the average content of Cd in the soil was higher than this standard. Multivariate statistical analysis indicated that Cd was the predominant pollutant and had strong correlations with Zn and Pb. The Cd content was most impacted by human activities, which also explained that this municipal solid waste incineration plant has little effect on Zn, Pb and Cd in the surrounding soil. The geo-accumulation index decreased in the order of Cd > Zn > Pb, and the geo-accumulation index of Cd was greater than 5, indicating that the pollution level for Cd was extremely heavy. The comprehensive potential ecological risk index (RI) of various heavy metals was greater than 1200, And the potential ecological risk level of the study area was high. The contribution rate of Cd to RI was relatively large, and Cd pollution should be paid more attention to.

Phytoremediation strategies for heavy metal-contaminated soil by selecting native plants near mining areas in Inner Mongolia.

Phytoremediation technology, as an eco-friendly and cost-effective approach, is widely used to restore soil contaminated by heavy metal(loid)s. However, the adaptability and absorption capacity of plants to multiple elements are the crucial factors affecting the application of phytoremediation in mining areas. In this study, dominant native plant species and their paired soils were collected near a lead-zinc mine in Inner Mongolia, to assess the ecological risk of heavy metal(loid)s and phytoremediation potential. The results showed that Cd and As were the dominant soil pollutants, with levels of 90.91% and 100%, respectively, exceeding the risk intervention values for soil contamination of agricultural land. The rates of Pb, Cu, and Zn exceeding the risk screening values were 69.70%, 60.61%, and 96.97%, respectively. Extremely high ecological risk of heavy metal(loid)s was observed in this area. The ability of native plants accumulating heavy metals varied among species. The bioconcentration factor (BCF) varied from 0.14 to 2.59 for Cd, 0.02 to 0.45 for As, 0.06 to 0.76 for Pb, 0.05 to 2.69 for Cr, 0.15 to 1.00 for Cu, and 0.22 to 4.10 for Zn. Chinese Cinquefoil Herb (Potentilla chinensis Ser.) showed the potential to accumulate multiple toxic elements based on the biomass, shoot content, translocation factor (TF), BCF, and metal extraction rate (MER), while, other species showed the potential to accumulate single toxic element: goosefoot (Chenopodium album L.), Lespedeza daurica (Laxm.) Schindl. and peashrubs (Caragana korshinskii Kom.), Herba Artemisiae Scopariae (Artemisia capillaris Thunb.), alfalfa (Medicago sativa L.), and Moldavian Dragonhead (Dracocephalum moldavica L.) for Cd, As, Cr, Cu, and Zn, respectively. Furthermore, wild leek (Allium ramosum L.), cogongrass (Imperata cylindrica (L.) Beauv.), fringed sagebrush (Artemisia frigida Willd.), and field bindweed (Convolvulus arvensis L.) were selected for phytostabilization of specific elements, considering the heavy metal contents in the roots and low TF values. This study provides a reference for selecting appropriate species for the remediation of heavy metal-contaminated soils in certain mining areas.

Biodegradation of Atrazine Herbicide: A Mini-review

Atrazine herbicide is known to disrupt the endocrine system and is potentially carcinogenic. The long-term use of this herbicide results in high residue levels in soil, causing water contamination of agricultural land. Microbial degradation of herbicide represents a cost-effective way of eco-restoration compared to the more expensive physicochemical methods, especially in soil settings. Growth and degradation of atrazine by microorganisms are optimal at specific concentrations, temperature, pH, inoculum size and hours of incubation. Previously isolated microorganisms have demonstrated high efficiency for atrazine biodegradation with a broad optimum pH and temperature. The metabolic pathway for biodegradation has been elucidated and reveals important characteristics. These organisms as suitable candidates for bioremediation of atrazine-polluted sites have shown great potential for atrazine degradation. This review aimed to catalogue and update the characteristics of isolated atrazine-degrading microorganisms to date.

Source Analysis and Pollution Assessment of Soil Heavy Metals in Typical Geological High Background Area in Southeastern Chongqing

In order to understand the pollution characteristics of soil heavy metals in typical geological high background areas in southeastern Chongqing, analyze its pollution sources, and put forward risk management and control suggestions, 211 topsoil samples (0-20 cm) were collected in Xinglong Town and Muye Township in the north of Youyang County, Chongqing City, and the contents of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and the soil pH value in the surface soil were analyzed. Additionally, mathematical statistics, pollution load index (P), potential ecological risk index (RI), correlation analysis, and the positive matrix factorization (PMF) model were used to study the content and spatial distribution characteristics of heavy metals in the topsoil, and pollution assessment and source analysis of heavy metals were carried out. The results showed that the average concentrations of heavy metals in the surface soil all exceeded the soil background value in Chongqing, showing different levels of enrichment. Among them, the proportion of Cd exceeding the screening value in the "soil environmental quality risk control standard for soil contamination of agricultural land" (GB 15618-2018) was as high as 83.41%, the proportion of exceeding the control value was 7.58%, and the potential risk was relatively high. The evaluation results of the pollution load index method showed that the study area was slightly polluted as a whole, and the evaluation results of the potential ecological risk index showed that the overall ecological risk of the study area was relatively high. Among them, the contribution rates of heavy metals Hg, Cd, and As were 50.27%, 28.63%, and 11.70%, respectively. The PMF results showed that there were three main sources of heavy metals in the soil in the study area:natural parent material sources, agricultural sources, and mixed sources of industrial activities and traffic emissions, accounting for 40.49%, 29.12%, and 30.39%, respectively. The quantitative source analysis results of soil heavy metals in the study area have important reference significance for soil heavy metal pollution control in geologically high background areas.

Integrated Analysis on Source-exposure Risk of Heavy Metals in Farmland Soil Based on PMF Model: A Case Study in the E-waste Dismantling Area in Zhejiang Province

In order to explore the characteristics and sources of heavy metals in farmland soil and their risks to human health and to provide an important scientific basis for farmland pollution control, 133 surface soils (0-20 cm) were collected from typical agricultural production areas in Zhejiang Province, and the contents of soil Cd, Pb, Cr, Cu, Zn, Ni, As, and Hg were determined. Various methods were applied to evaluate the degree of heavy metal pollution in farmland and its ecological risks in the study area. The method of combining Kriging interpolation and positive definite matrix factor analysis (PMF) was applied to analyze the pollution sources and quantify the contribution of each pollution source. Combined with the health risk assessment model, the risk to human health of each pollution source was evaluated from the perspective of source exposure. The results showed that the average ω(Cd), ω(Pb), ω(Cr), ω(Cu), ω(Zn), ω(Ni), ω(As), and ω(Hg) were 0.76, 65.22, 92.02, 103.92, 198.49, 36.65, 5.97, and 0.20 mg·kg-1, respectively. The average contents of Cd and Cu were higher than the risk screening values of soil contamination of agricultural land, and 85.71% and 96.24% of soil was contaminated by heavy metals. The average contents of Pb, Cr, Zn, and Ni exceeded the soil background values of the Wenhuang Plain in Zhejiang Province, and the As and Hg contents were within the limit values. The potential soil ecological risks were mainly light-moderate, accounting for 90.98%, and both high and higher risk accounted for 4.51%; Cd was the main potential ecological risk element. The main sources of heavy metal pollution in the study area were the sources of the electronic waste dismantling process (26.82%), the mixed sources of coal combustion and traffic emissions (34.50%), mixed sources of natural parent materials and agricultural inputs (25.59%), and e-waste pickling runoff and solid waste leaching sources (13.09%). The health risk of heavy metal exposure to children was significantly greater than that in adults. Mixed sources of natural parent materials and agricultural inputs contributed the most to human health risks, and Cr was the element with the greatest contribution to human health risks.

Metal-Tolerant Bioinoculant Pseudomonas putida KNP9 Mediated Enhancement of Soybean Growth under Heavy Metal Stress Suitable for Biofuel Production at the Metal-Contaminated Site

The contamination of agricultural land with heavy metals is a global concern. Agricultural products produced in heavy metal-contaminated soil are prone to metal accumulation, and thus, are less fitted for consumption due to food safety issues. The cultivation of biofuel crops in contaminated soil would provide immediate economic benefit to the landholders while simultaneously reclaiming contaminated sites in the long run. The use of edible soybean for biodiesel production is discouraged due to the negative impact on food security. However, soybean produced in metal-contaminated soil would be suitable for biodiesel production. In this study, the tolerance and metal bioaccumulation potential of Pseudomonas putida KNP9 for Pb and Cd is investigated, and KNP9 is tested for soybean growth enhancement in cadmium and lead-amended soil. The maximum metal tolerance for the Pb and Cd in KNP9 was 1580 µM and 546 µM, respectively. KNP9 was found to be effective in removing both Pb and Cd from the solution. SEM-EDX revealed that KNP9 bioaccumulates both Pb and Cd. In pot trial studies, KNP9 was found to be effective in enhancing soybean growth with respect to untreated control under lead and cadmium stress. Thus, KNP9 inoculation protects soybean plants from the detrimental effects of cadmium and lead stress. Therefore, metal bioaccumulating bacterium P. putida KNP9 inoculation in soybean is a promising strategy for soybean growth enhancement, which could be utilized for enhanced biodiesel production from soybean at metal-contaminated sites.

Pollution Characteristics and Risk Assessment of PAHs in the Soil of Wild Forsythia Suspensa in Shanxi

Shanxi is one of the main producing areas of Forsythia suspensa in China. In order to explore the safety of the soil in the areas where Forsythia suspensa grows,70 surface (0-25 cm) soil samples were collected from the main growing areas of F. suspensa in the eastsouth of Shanxi Province in July 2017. The concentration and composition characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in the sample soils were analyzed using chemical extraction and gas chromatography-mass spectrometry (GC-MS). The diagnostic ratio method was used to determine the source of PAHs in the areas. The potential ecological risk was assessed by using the method of calculating the equivalent carcinogenic concentration of benzo[a]pyrene. The results showed that the average concentration of total PAHs (Σ16PAHs) in all of the soil samples was 1.85 μg·g-1, which was dominated by three ring number PAHs, accounting for 76.7% of the total PAHs. The detection rates of phenanthrene (Phe) and anthracene (Ant) were both 100% of all the sample sites. The soil PAHs in the wild F. suspensa growing areas mainly originated from coal, biomass burning, and motor vehicle exhaust emissions, which resulted from air transport and sedimentation pathways. In all of the sample sites, the concentration of Σ16PAHs the limit standard level (0.2 μg·g-1) of Maliszewska-Kordybach for agricultural soil pollution and exceeded the soil heavy pollution level limit value (1.0 μg·g-1) in 41.4% of the sample sites. The concentration of BaP was above the risk control standard for soil contamination of agricultural land (0.55 μg·g-1) in 10% of all the soil samples. A total of 11.4% of the sample soil ΣBaPeq16PAHs and ΣBaPeq8BPAHs exceeded the agricultural soil screening value (0.55 μg·g-1). These results indicate that the contamination of PAHs was at a detectable level in the soil of wild F. suspensa growing in Shanxi, and thus their potential ecological risks should not be ignored. It is necessary to enhance the research regarding these areas to ensure the safe production of medicinal plants.

Distribution Characteristics, Ecological Risks, and Source Identification of Heavy Metals in Cultivated Land Under Non-grain Production

The purpose of this study was to explore the distribution characteristics and potential ecological risks of soil heavy metal pollution of cultivated land under non-grain production. Taking a typical area around Hangzhou Bay as an example, 254 topsoil samples (0-20 cm) of cultivated land were collected, and the content of eight soil heavy metals in four different cultivated land use types, including grain, seedlings, vegetables, and fruits, was analyzed. The ecological risk was assessed by the Nemerow pollution index and the potential ecological risk index, and the PMF model was used to identify the source of soil heavy metals in the study area. The results showed that the average contents of As, Cr, Cd, Cu, Hg, Ni, and Zn were all higher than the soil background value, except for Pb, but were lower than the national risk control standard for soil contamination of agricultural land. Non-grain production had a significant impact on the accumulation of heavy metals in soil. The content of heavy metals in nurseries and orchards was relatively high, followed by vegetable fields, and the lowest in grain fields. The Nemerow index showed that the cultivated land in the study area was in a light pollution level as a whole, and the single-factor pollution risks of Hg, Cd, and As were relatively high. The potential ecological risk levels of heavy metals in different cultivated land use types were:nurseries>orchards>vegetable fields>grain fields. The PMF results showed that the main sources of soil heavy metals in the study area were mixed sources of industrial emissions (36.8%), natural parent material sources (28.4%), atmospheric deposition sources (21.4%), and agricultural activity sources (13.4%). In conclusion, the increase in the application of chemical fertilizers and pesticides was the direct reason for the increase in soil heavy metal content caused by non-grain production of the cultivated land, whereas the industrial and mining emissions and atmospheric deposition accelerated the increase in soil heavy metal content in the study area.

Pollution Characteristics and Source Apportionment of Heavy Metals in Vegetable Field in the Three Gorges Reservoir Area (Chongqing Section)

To explore the pollution characteristics, ecological risks, and sources of heavy metals, soil surface samples of vegetable fields in 14 typical districts of the Three Gorges Reservoir area (Chongqing section) were collected in October 2021. The contents of seven types of heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) were analyzed. Based on the single-factor pollution index, the Nemerow integrated pollution index and potential ecological risk coefficient of heavy metals were evaluated. Additionally, the effects of different planting years and methods (open-field and greenhouse planting) on soil heavy metal accumulation were analyzed. The results indicated that the mean concentrations of heavy metals in vegetable soils in the area were lower than the national risk screening values for soil contamination of agricultural land (GB 15618-2018) but higher than their background values in Chongqing. According to the single-factor pollution index method, Pb, Zn, Cu, and Cd showed negligible slight hazards. The Nemerow pollution index showed that the study area was at a slight hazard level, and the main factors were Ni and Cd. Heavy metal pollution was found in 91.4% of the soil samples (PN>1) with different degrees, and 9.19% of them were severely polluted. The potential ecological risk coefficient showed that the vegetable lands were polluted slightly, and 9.77% of soil samples polluted by Cd were at moderate ecological risk. According to cluster analysis, the sources of Cd-Cu-Pb-Zn and As-Cr-Ni were similar. The content of heavy metals in the open field and greenhouse showed an increasing trend with the increase in planting years, and the content of heavy metals in greenhouse soil were generally higher than that in open field soil.

Ecological risk assessment and early warning of heavy metal cumulation in the soils near the Luanchuan molybdenum polymetallic mine concentration area, Henan Province, central China

The Luanchuan molybdenum polymetallic mine concentration area is rich in mineral resources and has a long history of mining. The environmental impact of long-term mining activities cannot be ignored. It is of great significance to study the ecological risk and the accumulation trends of heavy metals in the soil of mining areas for scientific prevention and control of heavy metal pollution. Taking the Taowanbeigou River Basin in the mine concentration area as the research object, the ecological pollution risk and cumulative effect of heavy metals in the soil of the basin were studied by using the comprehensive pollution index method, potential ecological risk assessment method and geoaccumulation index method. On this basis, the cumulative exceeding years of specific heavy metals were predicted by using the early warning model. The comprehensive potential ecological risk of heavy metals in the soil near the Luanchuan mine concentration area is moderate, and the single element Cd is the main ecological risk factor, with a contribution rate of 53.6%. The overall cumulative degrees of Cu and Pb in the soil are “none-moderate”, Zn and Cd are moderate, Mo has reached an extremely strong cumulative level, Hg, As and Cr risks are not obvious, and the overall cumulative risks order is Mo>Cd>Zn>Cu>Pb>Hg. According to the current accumulation rate and taking the risk screening values for soil contamination of agricultural land as the reference standard, the locations over standard rates of Cu, Zn and Cd will exceed 78% in 90 years, and the over standard rate of Pb will reach approximately 57% in 200 years. The cumulative exceeding standard periods of As, Cr and Hg are generally long, which basically indicates that these elements do not pose a significant potential threat to the ecological environment. Mining activities will accelerate the accumulation of heavy metals in soil. With the continuous development of mining activities, the potential pollution risk of heavy metals in the soil of mining areas will also increase.©2023 China Geology Editorial Office.

Accumulation Characteristics and Health Risk Assessment of Heavy Metals in Soil-Crop System Based on Soil Parent Material Zoning

This study used both the element occurrence form analysis and the chronic health risk assessment method to investigate the accumulation characteristics of heavy metals in the soil-crop system and the health risk assessment of agricultural products in northeastern Yunnan, which is a typical area of Southwest China where heavy metals are enriched in soil. Based on the study of 1137 groups of agricultural products and corresponding root soils, the results showed that the soil cadmium (Cd) and lead (Pb) in the lead-zinc ore concentration area were higher than the risk-intervention values of the "Soil Environmental Quality Risk control standard for soil contamination of agricultural land" (GB 15618-2018), whereas the soil Cd in the other parent material areas was within the screening-intervention buffer zone, and Pb was below the minimum risk-screening value. According to the National Food Safety Standard of China (GB 2762-2017), the heavy metal Cd in potatoes and soybeans in the area seriously exceeded the standard, the heavy metal Pb in tartary buckwheat and walnut exceeded the limit value, and the exceeding rate of heavy metal Cd in crops from these parent material areas showed: clastic rock>basalt>lead-zinc ore>carbonate ≈ Quaternary sedimentary>sand (mud) rock. According to the U.S. Environmental Protection Agency's assessment method for the chronic health risk of heavy metal intake by humans, the grains and potatoes, staple foods, and fruits had low chronic health risks of heavy metal intake. Agricultural products from the parent material area of clastic rock, sand (mud) rock, Quaternary sedimentary, and lead-zinc ore concentration showed health risks; with the change in soil physical and chemical properties and the increase in the types of edible crops, the risk will gradually increase. Based on this research, it is urgent to carry out real-time monitoring of agricultural products in the area.

Distribution and Source Apportionment of Heavy Metals in Soil around Dexing Copper Mine in Jiangxi Province, China

The soil heavy metal pollution around the mine threatens crop growth and human health. Intensively studies of the distribution characteristics and source of soil heavy metals around some typical mines are very crucial for environmental management and green development of mine. A total of eighty-nine soil samples, twenty-one sediment samples, five waste rock samples and two tailing sand samples were sampled to investigate copper (Cu), lead (Pb), zinc (Zn), arsenic (As), cadmium (Cd), chromium (Cr) and mercury (Hg) in soil, sediment, waste rocks and tailings sand around Dexing Copper Mine, Jiangxi Province, China. The concentrations of the seven heavy metals were determined using inductively coupled plasma mass spectrometry ICP-MS/atomic fluorescence spectroscopy (AFS). The Igeo values of soil heavy metal showed that 100% of Cu were at an unpolluted-to-moderately-polluted level (Igeo > 0), more than 50% of Cu were heavily polluted (Igeo > 3), 65.16%, and 22.47%, 7.86% and 7.87% of the soil samples for Cd, Hg, As and Zn were overly moderately polluted (Igeo > 1). A total of 13.48% and 11.24% of the soil samples for Pb and Cr, respectively, were moderately polluted (1 < Igeo < 2). The concentrations of heavy metals in soil were Compared with Risk Screening Values for Contamination of Agricultural Land (RSVCAL), with the concentration of 97.75% soil samples for Cu, and 69.21% of soil samples for Cd were higher than RSVCAL. In Dawu river basin the concentration of 50% soil samples for Pb were higher than RSVCAL. According to Igeo and RSVCAL, the soils around Dexing Copper Mine were polluted by heavy metals to some extent, with especially the Cu pollution of soil being the most serious. These heavy metal concentrations exceeding RSVCAL have threatened the safety of agricultural products. The results of soil profile analysis, principal component analysis (PCA) and cluster analysis (CA) indicated that the mining activities of Dexing copper mine should be the main source of Cu in the soil. High As concentration in soil obviously caused by the copper mine as well. In addition, Dexing Copper Mine should partly account for soil pollution by Zn, Pb, Cd, Hg and Cr around the mine.

Методологический подход к оценке риска производства продукции, не соответствующей нормативным требованиям по содержанию Cs-137 и Sr-90

Radioactive contamination of agricultural lands necessitates the need for developing robust methods, tools and techniques that could, on the one hand, minimize the levels of radionuclides in food products, and on the other hand, facilitate in making informed decisions on economic efficiency of farmland use for the production of different types of foods. Following the Chernobyl nuclear accident, significant farmland areas of the Republic of Belarus were affected by radionuclide contamination of technogenic origin. The main soil contaminants nowadays, after the decay of short-lived nuclides, are Cs-137 и Sr-90. Given that a food product from a contaminated farmland may contain both radionuclides, Cs-137 and Sr-90, the risk of its non-compliance with the established maximum permitted levels of contamination should be assessed not only with regard to each individual radionuclide but also for the both of them simultaneously. Using the risk matrix, significance level criteria and rank assignment, the author proposes a new methodological approach for assessing the risk of non-compliance of the produced agricultural foods to the regulatory requirements, accounting not for either but for both radionuclides (Cs-137 and Sr-90) simultaneously. The use of the risk assessment methodological approach for the agricultural produce non-compliances with the food safety standards regulating the contents of Cs-137 and Sr-90 enables one to make substantiated and scientifically justified decisions on the efficiency of landuse for the particular foodstuff production and/or identify the farmlands where radiation-associated food production restrictions could be lifted.

Забруднення угідь унаслідок бойових дій: огляд рішень для подолання кризи

The purpose of this work is to analyze the types of pollution on the lands that have undergone hostilities and to review scientific research on this topic in order to find rational technological solutions to overcome the crisis. Methods and materials. The study is aimed at reviewing open scientific literary sources regarding the contamination of agricultural lands affected by the conduct of military operations. The research focuses on physical and chemical disturbances in the soil caused by military actions (bombing of land, land contamination by shrapnel remains, soil compaction by military equipment, chemical pollution by heavy metals, etc.) and land restoration methods. Research results. The primary task in eliminating the consequences of hostilities is the demining of land areas. There is a wide range of types of means for finding mines and machines for demining, in which the working body can be a reactive explosive device or a mechanical system in the form of a bucket, rollers of a rotating rotor, etc. Reclamation of lands disturbed as a result of military operations is carried out in two stages: technical and biological. The essence of the technical stage is to prepare the territories for the next target use. It consists in planning, as well as applying soil or fertile rocks to a leveled surface. The biological stage is a set of measures to restore the fertility of disturbed lands. It covers agrotechnical and reclamation measures aimed at restoring flora and fauna. To overcome the consequences of soil pollution by oil products and to compensate for nitrogen losses on land due to burning of fields, it is advisable to use active oil-oxidizing and regenerating soil microorganisms, by applying them with tillage and seeding units equipped with devices for applying liquid and dry complex fertilizers. Conclusions. Among the practical agrotechnical approaches to soil restoration after rough reclamation of land, the following can be distinguished: cultivation of bioenergy crops on damaged lands; application of minimal tillage technologies using organic waste and microbiological preparations; biotechnologies of soil remediation. In view of the technical and technological solutions of soil treatment for land restoration, each of the following consequences requires a special approach. Reclamation of damaged lands is advisable when experts estimate the terms of restoration of economic activity at no more than 15 years. If the soil cover needs a longer period for recovery, land conservation is carried out. Key words: soil pollution, hostilities, reclamation, remediation, land reclamation, soil treatment.

Dynamics of 137Cs and 90Sr content in the soil cover of agricultural lands in Zhytomyr region

The article examines the results of monitoring radionuclide contamination the soils of Zhytomyr region with 137Cs and 90Sr. We summarized the results of agrochemical certification of agricultural land for the period of research in 2006–2020 years (IX–XI rounds). For field and laboratory research, methods of agrochemical certification of agricultural lands and gamma-surveying of the territory and determination of the specific activity of 137Cs and 90Sr in soil samples were used. It was established that during the 36 years that have passed since the accident, the radiation state of the territory of Zhytomyr region has currently stabilized and is formed mainly under the influence of long-lived radionuclides cesium-137 and strontium-90. During the time that passed after the accident, only due to natural radioactive decay, the activity of the isotopes 137Cs and 90Sr decreased approximately by half. This was facilitated by natural processes and the implementation of measures to prevent the removal of radionuclides beyond the exclusion zone. Turf-podzolic soils, which are most common in the Polissia zone, are characterized by high sorption capacity and weak migration along the 137Cs profile. It was established that the number of agricultural lands contaminated with 137Cs and 90Sr with a density <5.0 Ki/km2 and <0.15 Ki/km2 is 99.9% and 99.5%, respectively, the density of land soil contamination in the section of the surveyed areas with 137Cs pollution varied from 0.07 to 3.41 Ki/km2, and 90Sr from 0.013 to 0.164 Ki/km2, therefore, according to current legislation, the soils are considered conditionally clean. A direct correlation between the indicators of the reaction of the soil solution with 137Cs contamination (r=0.94) and a significant correlation with 90Sr contamination (r=0.69) was revealed. A moderate correlation (r=0.40) was found between the indicators of the density of contamination of agricultural land with radionuclides 137Cs and 90Sr. It is emphasized that the use of the land fund of Zhytomyr region requires constant monitoring of soil fertility and contamination with radionuclides. The implementation of the task is possible under the condition of permanent soil and agrochemical monitoring, which is conducted by carrying out agrochemical certification of agricultural lands.