Concentrations Of Elements In Soils Research Articles

Investigation of in-field heterogeneities in the development of soybean according to remote sensing data and properties of the plow horizon (on the example of the south of the Far East)

Assessment of crop heterogeneities is one of the key conditions for predicting crop yield and increasing the economic efficiency of farming. The aim of the study is to develop methods for assessing in-field heterogeneities of soybean based on remote sensing data and to determine the relationship between soybean productivity indicators and soil characteristics. The work was carried out on meadow-brown heavy loamy soil, 10 plots of soybean field with a total area of 36.9 ha (Khabarovsk Krai) were selected for sampling in May and August 2023. The research was based on the results of remote sensing data processing (Sentinel-2 satellite, DJI Mavic3M quadrocopter), assessment of soybean productivity indicators, agrochemical, physical and chemical characteristics of soils and micro- and macroelement composition. The spatial distribution of NDVI modeled from Sentinel-2 data (early August) corresponded to the distribution of NDVI from DJI Mavic3M data. NDVI index values in August 2023 were found to be significantly correlated with soybean height (R = 0.64) and number of beans (R = 0.64). Soil moisture has a positive correlation with NDVI (R = 0.87) and soybean height (R = 0.68) for the entire growing season of the crop. NDVI was positively correlated with Hg (R = 0.79) and negatively correlated with pH (R = –0.79). The content of N-NO3 ranged from 2.51 to 6.84 mg/kg (V = 35.12 %), mobile forms of Р2О5 – from 2.47 to 6.07 mg/100 g (V = 33.13 %), К2О – from 4.98 to 9.37 mg/100 g (V = 20.07 %). The variability of N-NO3 and Р2О5 content decreased to 11.61 % and 21.99 % by August. No significant changes in soil bulk composition were observed between the first and second sampling. Variation of content of rare-earth elements (Sc, Y, lanthanides) in the selected sites did not exceed 5 %. By the date of the second sampling a significant decrease by 4–10.5 % (p 0.05) in the content of rare earth elements in soil was noted.

Using Microplates to Test Boron in Zea mays Leaf Plant and the Surrounding Soil

Background: Boron plays a crucial role in cell wall construction in plants and also facilitates the transfer of carbohydrates, which are essential for various physiological processes. The objective was to measure element concentrations in soil, water extracts and plant tissues (Zea mays) using Azomethine-H and ICP-MS within a controlled microplate assay. Methods: A microscopic plate repeat test was used to analyze the concentration of boron in soil extracts and plant tissue ash from local Zea mays leaves, considering the global trend in environmental sustainability. Tests aimed to modify the azomethine-H microscopic approach to eliminate pH and chemical interferences in soil samples and plant tissues. Due to their ability to ensure sample repeatability and quality control, micro spectrophotometers are ideal for high-throughput analysis. Result: The microplate test has enhanced boron measurement in soil and plant tissue samples. Our improvements to the microplate B assay have resulted in more accurate boron measurements in these samples. Microplate B testing is effective and suitable analysis in modern research and laboratories, using 40 times less chemical reagent per sample than traditional spectrophotometry. Additionally, microplates enable simultaneous analysis and calibration of samples. The modified plate test significantly improves boron measurement in soil and plant tissue samples, using 40 times fewer reagents than traditional spectrophotometry. This method is cost-effective, ideal research, commercial analysis and making it a valuable tool for modern laboratories.

Microhabitat influences on phage-bacteria dynamics in an abandoned mine for ecorestoration

Understanding the complex interactions between bacteriophages (phages) and bacteria within varied environmental niches is critical yet underexplored for improving microbe-assisted ecological restoration. This study investigates the influence of microhabitat heterogeneity within an abandoned mine on phage-bacteria interaction patterns, focusing on Pseudomonas-enriched bacterial communities. By isolating viral communities and purifying bacteria from soils of three distinct microhabitats, we assessed the regulatory role of environmental factors on these interactions, crucial for bacterial success in environmental applications. We characterized microhabitat variability by analyzing soil particle size fractions, minerals composition, and elemental content using X-ray diffraction and energy-dispersive X-ray analyses. 16S rRNA sequencing and cross-infection assays revealed that although bacterial communities across different microhabitats are taxonomically similar, their interaction patterns with phages are distinct. Phage communities showed nonselective infectivity across soil types, while bacterial communities exhibited selective adaptation, facilitating colonization across diverse microhabitats. Minerals such as mica, kaolinite, and hematite were found to increase phage infectivity, whereas mixed-layer clay correlated with early lysis. Additionally, higher levels of iron (Fe) and potassium (K) were linked to bacterial resistance strategies. Our findings highlight the importance of understanding asymmetric adaptive strategies between bacteria and phages, driven by microhabitat heterogeneity, for enhancing microbial-mediated nature-based restoration of degraded ecosystems.

Content, Sources, and Ecological Risk Assessment of Heavy Metals in Soil of Typical Karst County

Soil heavy metals in karst areas have obvious high background value characteristics. Conducting county-level soil heavy metal ecological risk assessment and identifying heavy metal sources in karst areas are of great significance for soil pollution control and land resource management. Taking Pingguo City, a typical karst county in Guangxi Province, as the study object, 3 151 surface and deep soil samples were collected using the grid method and combined to form 785 analytical samples. The contents of eight heavy metal elements, including As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, were determined. The content characteristics and sources of heavy metals were analyzed using statistical analysis, interpolation analysis, factor analysis, and the absolute principal component-multiple linear regression model （APCS-MLR）. Using the content of heavy metal elements in deep soil （150-200 cm） as background values, the ecological risk assessment of heavy metals in surface soil （0-20 cm） in the study area was conducted using the geo-accumulation index （Igeo） and potential ecological risk index （RI） methods. The results showed that the average content of heavy metal elements in the deep soil of the study area was significantly higher than the background value of the C layer soil in Guangxi Province, and the average content of heavy metal elements in the surface soil was significantly higher than the background value of the A layer soil in Guangxi Province. The spatial distribution of soil heavy metal element content generally showed the characteristics of high in karst areas and low in non-karst areas. The main sources of As, Cr, Ni, Pb, and Zn were soil parent materials, with contribution rates of 74.36%, 84.59%, 93.69%, 79.67%, and 78.17%, respectively. The main sources of Cd were soil parent material sources and unknown sources, with contribution rates of 37.33% and 31.05%, respectively. The main sources of Cu were soil parent materials and unknown sources, with contribution rates of 59.07% and 40.23%, respectively. The main sources of Hg were tectonic activity and mineralization, as well as unknown sources, with contribution rates of 52.49% and 30.65%, respectively. The geo-accumulation index （Igeo） showed that the surface soil was mainly polluted by Cd, with mild or above pollution accounting for 47.78%. The potential ecological risk index （RI） showed that the proportion of surface soil heavy metal comprehensive potential ecological hazards with mild, moderate, strong, and very strong levels was 80.78%, 14.97%, 2.51%, and 1.64%, respectively.

Assessment of potential toxic elements in soils, sediments, and vegetation in the surroundings of Anapa, Russia.

The study presented here reports the concentration of major, trace, and rare earth elements in soil, sediments, and vegetation samples collected from 13 locations around Anapa City located on the northern coast of the Black Sea in Russia. The neutron activation analysis technique has been used to fulfill this objective. Along with this, the bioconcentration and translocation factors were calculated. Overall, the content of 31 elements was detected in soil and sediments while 20 elements were determined in three types of vegetation: macroalgae (Cystoseira sp. and Ulva sp.), aquatic plants (Phragmites australis), and sea grass (Zostera sp.). The quantified concentration followed the order soil > sediment > vegetation. The phytotoxic levels for Zn, V, Mn, and Fe have been quantified as the highest. Bromine was the most abundant and accumulated in Phragmites australis. Based on the results obtained from this investigation, there is a possibility of contamination in the study area.

Natural restoration of arsenic-contaminated environment with Quercus robur L. and Tilia cordata Mill.: 5-Year longitudinal study of dendroremediation dynamics

Investigating natural processes in arsenic (As) polluted areas and plants that have naturally chosen to grow there pose practical restoration recommendations. This study aimed to assess long-term changes in natural As dendroremediation dynamics for Quercus robur L. and Tilia cordata Mill., tree species capable of growing in areas polluted by mining activities. We examined total As and its forms, as well as B, Ca, K, Mg, Na and P, in soil and trees over 5 years. We also characterized pH and EC of soil, examined proline content in tree organs, and calculated Bioconcentration Factor (BCF) and Translocation Factor (TF) for As.Initial As concentrations in soil were 37.0 mg kg⁻1 under Q. robur and 34.7 mg kg⁻1 under T. cordata, significantly decreasing after 5 years to 10.5 mg kg⁻1 and 9.51 mg kg⁻1, respectively. This corresponds to pollution reduction of up to 71.8%. A notable decrease in As(III) and dimethylarsinic acid, along with increase in other organic As forms in soil, was observed. Additionally, concentrations of essential elements in soil, as well as its pH and EC, decreased over time.Both tree species accumulated substantial amounts of As in their organs, but the dynamics of this process were species-specific. During first 4 years, T. cordata accumulated more As and exhibited higher BCF, but in the 5th year, it was clearly surpassed by Q. robur. The highest TF was calculated for Q. robur in year 3, and for T. cordata in years 2 and 3. Generally, limited aboveground movement of As was indicated: BCF >1 were calculated for years 2 and 3, while TF were consistently <1. Proline content increased significantly in all organs, correlating with As, especially in Q. robur. In contrast, Q. robur leaves mapping revealed stable macroelement distributions, but clear variations were observed for T. cordata., which may suggest specific reaction to stress.These findings suggest that both species can effectively restore As-polluted areas, though with different dynamics. The selection of species for dendrorestoration should be based on whether the goal is faster remediation with lesser overall reduction (e.g. T. cordata) or slower remediation with ultimately greater pollution reduction (e.g. Q. robur).

Effects of long-term nighttime warming on extractable soil element composition in a Mediterranean shrubland

Understanding the soil biogeochemical responses to increasing global warming in the near future is essential for improving our capacity to mitigate the impacts of climate change on highly vulnerable Mediterranean ecosystems. Previous studies have primarily focused on the effects of warming on various biogeochemical processes. However, there is limited knowledge about how the changes in water availability associated to high temperatures can alter the bioavailability and dynamics of soil elements, thereby impacting ecosystem productivity, species composition, and pollution through soil biogeochemical and hydrological processes. In this study, we investigated the effects of long-term nighttime warming on the extractable concentrations of organic carbon (EOC), total nitrogen (ETN), total phosphorus (ETP), and 17 mineral elements (arsenic (As), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), sulfur (S), strontium (Sr), vanadium (V), and zinc (Zn)) through environmental experiments in a semi-arid Mediterranean shrubland. We explored the potential biotic and abiotic mechanisms underlying the seasonal and long-term changes in extractable-mobilizable elemental composition and concentrations. Our findings revealed that prolonged warming led to higher mean annual soil temperature (with an average increase of 0.67 °C from 1999 to 2014), accumulation of soil organic matter (EOC) and extractable concentrations of soil elements (particularly increased ETP and extractable Ca, Mg, Cu, Sr, Mn, and As). These changes were attributed to uniformly higher activities of extracellular soil enzymes and/or lower plant photosynthetic and nutrient uptake capacity linked to more water deficit under warmer conditions. Seasonality unevenly altered element extractable concentrations, with soil microclimate (temperature and water content) and biological (soil microbial and plant) activity being the main drivers of this variability, thus influencing soil element composition. These results suggest significant fluctuations in the extractable concentrations of specific mineral elements in these soils, implying potential future variations in soil element composition as well as the loss of total element concentrations/contents in semi-arid Mediterranean ecosystems due to increasing warming. Therefore, these findings enhance our ability to predict ecosystem management strategies and mitigate the observed negative impacts on plant-soil systems and water quality in the context of climate change.

Changes in Individual and Group Compositions of Polyphenols in Leaves of Lonicera caerulea subsp. altaica and Spiraea chamaedryfolia as Related to Chemical Element Contents in Soil and Plants on Ultra-alkaline Parent Rock Material.

Using high-performance liquid chromatography (HPLC), the contents of main classes of biologically active polyphenols in leaf extracts were analyzed in the medicinal species Spiraea chamaedryfolia L. (Rosaceae) and Lonicera caerulea subsp. altaica L. (Caprifoliaceae). Their features were studied in relation to the macroelement and trace element contents in soil and phytomass in sites with sporadic occurrence of serpentinites in the Altai Mountains. A total of 16 polyphenolic compounds were identified for the first time in S. chamaedryfolia leaf extracts. Of these, three compounds were attributed to phenol carboxylic acids; ten, to flavonols; two, to flavones; and one was identified as a flavanone. In L. caerulea subsp. altaica, the analysis confirmed the polyphenolic composition measured earlier, including hydroxycinnamic acids, flavonols, and flavones, and identified an additional compound as a flavanone. Species-specific shifts in plant secondary metabolism were found to occur in response to specific edaphic properties and the accumulation of macroelements and trace elements in leaves of plants growing in an area with a natural geochemical anomaly.

DYNAMIC SOIL PROPERTIES AFFECT THE ACIDITY OF ARTIFICIAL WETLANDS: A CASE STUDY IN THUNG YIEW PAK PHLI OF NAKHON NAYOK PROVINCE, THAILAND

This study examined the soil elements and properties of an area becoming an artificial wetland and compared them with those of an agricultural area. The study site is an artificial wetland in Nakhon Nayok Province, Thailand. Its soil properties and element content were compared with a nearby agricultural area using a one-way analysis of variance (ANOVA). The results of the study found this artificial wetland to be within the soil acidity zone of central Thailand, with an average soil pH above 3.99 ± 0.49 and a topsoil organic matter average of 17090 ± 2685 mg kg-1, with aluminium (Al) and iron (Fe) as the major soil minerals. Compared to the agricultural area, the soil properties of the artificial wetland had slightly lower topsoil pH but significantly lower pH in the soil layer 100 cm deep in the agricultural area, and the EC in the artificial wetland was higher than in the agricultural area. However, there are three distinct patterns in the elemental composition of the artificial wetland: (1) A lower-quantity soil surface that improves with depth, (2) a high-quantity of topsoil that worsens with depth, and (3) highly variable soil quality below 50-100 cm. In the soil, the organic carbon in artificial wetlands has a ratio of 1:0.17:0.51 to reference area 1 and reference area 2, indicating that wetlands can store carbon in the soil. The element content of the topsoil and 50 cm soil layer is potentially influenced by land use and beneficial microbial activity, and the soil 100-150 cm layer has an element quantity shared with its parent soil. In this study, we sought to understand the physics and chemical composition of soil in an area transitioning to an artificial wetland over approximately 30 years.

Potential toxic elements (PTEs) in rhizosphere soils and crops under a black shale high geological background: Pollution characteristics, distribution and risk assessment

The LouShao Basin in Hunan Province is covered with two sets of black rock series containing various potential toxic heavy metal elements. The rock series are rich in various potential toxic heavy metal elements, and the weathered black shale is the main formation of local farmland soil, making it a typical area with high geological background in China. The purpose of this study is to assess the regional ecological and health risks by studying the correlation between the content of heavy metal elements enriched in rhizosphere soil, non-rhizosphere soil, and crops, and the concentration of heavy metal elements in the main source, black shale rocks. The results show that the elements in the black shale far exceed the world average of rock, severely affecting soil element concentrations. Se element is the most severely polluted in rhizosphere soil, exceeding the background value by 7 times. The concentration of heavy metals between rock-non-rhizosphere soil-rhizosphere soil-crops decreases linearly. The distribution of pollution has strong spatial autocorrelation, and the high geological background is the main reason. Pollution index results show significant pollution of Se, Cr, Hg, and Cd in crops, with the pollution of heavy metal element Cr in corn being extremely serious with Igeo = 6.71. The ecological risk order is Se > Cd > Cr > As > Pb > Hg. Humans mainly contact elements through skin contact and food chain intake. The HI value of heavy metal element Cd is greater than 1, indicating a high carcinogenic risk. Human exposure to Cd through skin contact and food chain intake may lead to related diseases such as kidney stones, and pose greater harm to children.

Impact of Land Use on Peat Soil Elemental Content and Carabidae and Plant Species Composition and Abundance

This study, conducted in 2020–2022, was designed to determine the impact of livestock grazing on habitat biodiversity and Carabidae beetles. Two research plots (a meadow and a pasture) were established on a farm in the village of Otapy, located in the agricultural catchment area of the Nurzec River in Eastern Poland. They were located next to each other so that they would possess the same set of atmospheric phenomena and processes shaped by the physical and geographical characteristics of the area. The study showed that the pasture was the richest in terms of the magnesium and calcium contents, while the meadow had significantly higher levels of phosphorus and zinc. The study also showed some differences in the abundance and species composition of plants and animals. The meadow had higher biodiversity, while the pasture was dominated by grasses. A disparity in the abundance of individual species was also presented. The study indicated the preference of individual species for particular forms of land use. Anisodactylus binotatus, Harpalus rufipes and Poecilus cupreus were most abundant in the meadow, while Carabus granulatus and Pterostichus melanarius were mostly represented in the pasture. The number of species, on the other hand, was the same. Our research concluded that proper landscape management through different uses affects plant and beetle diversity and soil element content.

Toxic element characterization against a typical high geology background: Pollution enrichment, source tracking, spatial distribution, and ecological risk assessment

The geological environment determines the initial content of various elements in soil, while the late input of toxic elements produced through weathering and leaching is a persistent threat to food security and human health. In this study, we selected the Lou Shao Basin, a black rock system background, and combined geostatistical analysis and multivariate statistics to quantify the specific contribution of weathering of the black rock system, and to analyze the source traces, spatial distributions, and ecological risks of the soil toxicity of elements. The results show that the soils in the study area are acidic, which is related to the weathering of sulfides in the black rock system. The concentrations of most elements in the soil were determined to exceed the soil background values, and the Cd, Se and N contents, exceeded more than five times, especially Se, Mo nearly as high as 13 times. Strong positive correlation between Se, Cu, V and P, low correlation between N and Se, Cu, V, P, Ni and Cd.72.52%, 43%, 77.79%, 82%, 77%, and 44.1% of Cd, Se, Ni, Cu, B, and Mo came from the black rock system, respectively, which were greatly affected by geogenic weathering; V, Zn, Pb, and As are mainly from biomass burning sources; N and P are mainly from agricultural surface sources. Comparison found that the Cd and Se elements in the rocks in the study area were 16.78 times and 1.36 times higher than the world shale average, respectively, and need to pay attention to the weathering process of the two, and the spatial distribution of the 12 elements in soils showed a striped and centralized block distribution pattern, specifically around the distribution of carbonate and metamorphic rocks and other high-geology blocks. The ecological risk results showed that Cd was the main element causing high ecological risk, followed by Se and N, which were at moderate to high ecological risk levels, and Se and N showed similar ecological risk patterns, which may be related to the fact that selenium can promote the uptake and transformation of nitrogen. The present results add to the endogenous sources of toxic elements, quantify the source contributions of toxic elements in soils with high geologic backgrounds, fill this knowledge gap, and provide new insights for pollution control and ecological protection in areas with high geochemical backgrounds.

Assisting nickel agromining using sustainable amendments

AbstractOne of the challenges of agromining is the adoption of more environmentally‐friendly solutions to improve plant biomass yields and Ni concentrations in plants. Here, we focused on four sustainable solutions for optimizing nickel phytoextraction by the hyperaccumulator Odontarrhena chalcidica: a biostimulant, another biostimulant/plant defense stimulator, artificial root exudates, and a biodegradable metal chelator. Their effects on the growth and physiology of O. chalcidica, on Ni phytoextraction capacity, on physicochemical soil characteristics, and on the diversity of rhizosphere and endophytic bacteria were compared to a conventional mineral fertilizer. A 5‐month pot experiment was carried out with O. chalcidica growing on an ultramafic soil. Element concentrations in both soil and plant were measured. Moreover, numerous compounds were analyzed (photosynthetic pigments, malondialdehyde, flavonoids, free amino acids, and starch). We also characterized rhizosphere and endophytic bacterial communities associated with this hyperaccumulator. Biostimulants appeared to be a promising way of improving Ni concentration in shoots and plant biomass production, and showed a positive effect on bacterial richness and diversity. In contrast, our experiments did not show that artificial exudates and mineral fertilizer had a positive effect on Ni phytoextraction. Finally, the biodegradable chelator had no significant effect. The use of sustainable amendments into a Ni agromining system improved both plant biomass and Ni yields, in comparison to mineral fertilization. Thus, improving agromining by replacing mineral fertilizers would be an eco‐efficient strategy.

A tool for assessing the sensitivity of soil-based approaches for quantifying enhanced weathering: a US case study

Enhanced weathering (EW) of silicate rocks spread onto managed lands as agricultural amendments is a promising carbon dioxide removal (CDR) approach. However, there is an obvious need for the development of tools for Measurement, Reporting, and Verification (MRV) before EW can be brought to scale. Shifts in the concentration of mobile elements measured in the solid phase of soils after application of EW feedstocks can potentially be used to track weathering and provide an estimate of the initial carbon dioxide removal of the system. To measure feedstock dissolution accurately it is necessary to control for the amount of feedstock originally present in the sample being analyzed. This can be achieved by measuring the concentration of immobile detrital elements in soil samples after feedstock addition. However, the resolvability of a signal using a soil mass balance approach depends on analytical uncertainty, the ability to accurately sample soils, the amount of feedstock relative to the amount of initial soil in a sample, and on the fraction of feedstock that has dissolved. Here, we assess the viability of soil-based mass-balance approaches across different settings. Specifically, we define a metric for tracer-specific resolvability of feedstock mass addition (φ) and calculate the feedstock application rates (a) and dissolution fractions (b) required to resolve EW. Applying calculations of a, b, and φ to a gridded soil database from the contiguous USA in combination with known compositions of basalt and peridotite feedstocks demonstrates the importance of adequately capturing field heterogeneity in soil elemental concentrations. While EW signals should be resolvable after ~1–3 years of basalt feedstock addition at common application rates for most agricultural settings with adequate sampling protocols, resolving EW in the field is likely to be challenging if uncertainties in tracer concentrations derived from field-scale heterogeneity and analytical error exceed 10%. Building from this framework, we also present a simple tool for practitioners to use to assess the viability of carrying out soil-based EW MRV in a deployment-specific context.

Warming affects leaf light use efficiency and functional traits in alpine plants: evidence from a 4-year in-situ field experiment.

Light use efficiency (LUE) is a crucial determinant of plant productivity, while leaf functional traits directly affect ecosystem functions. However, it remains unclear how climate warming affects LUE and leaf functional traits of dominant species in alpine meadows. We conducted a 4-year in-situ field warming experiment to investigate the eco-physiological characteristics for a dominant species (Elymus nutans) and a common species (Potentilla anserina) on the Tibetan Plateau. The leaf traits, photosynthesis and fluorescence characteristics were measured, along with the soil physical-chemical properties associated with the two species. Experimental warming increased the leaf LUE, maximum photochemical efficiency, non-photochemical quenching, relative water content and specific leaf area for both species. However, there was a decrease in leaf and soil element content. Different species exhibit varying adaptability to warming. Increasing temperature significantly increased the photosynthetic rate, stomatal conductance, transpiration rate, total water content, and specific leaf volume of E. nutans; however, all these traits exhibited an opposite trend in P. anserina. Warming has a direct negative impact on leaf LUE and an indirectly enhances LUE through its effects on leaf traits. The impact of warming on plant photosynthetic capacity is primarily mediated by soil nutrients and leaf traits. These results indicate that the two different species employ distinct adaptive strategies in response to climate change, which are related to their species-specific variations. Such changes can confer an adaptive advantage for plant to cope with environmental change and potentially lead to alterations to ecosystem structure and functioning.

Effects of plant growth-promoting rhizobacteria on blueberry growth and rhizosphere soil microenvironment.

Plant growth-promoting rhizobacteria (PGPR) have a specific symbiotic relationship with plants and rhizosphere soil. The purpose of this study was to evaluate the effects of PGPR on blueberry plant growth, rhizospheric soil nutrients and the microbial community. In this study, nine PGPR strains, belonging to the genera Pseudomonas and Buttiauxella, were selected and added into the soil in which the blueberry cuttings were planted. All the physiological indexes of the cuttings and all rhizospheric soil element contents were determined on day 6 after the quartic root irrigation experiments were completed. The microbial diversity in the soil was determined using high-throughput amplicon sequencing technology. The correlations between phosphorus solubilization, the auxin production of PGPR strains, and the physiological indexes of blueberry plants, and the correlation between rhizospheric microbial diversity and soil element contents were determined using the Pearson's correlation, Kendall's tau correlation and Spearman's rank correlation analysis methods. The branch number, leaf number, chlorophyllcontentand plant height of the treated blueberry group were significantly higher than those of the control group. The rhizospheric soil element contents also increased after PGPR root irrigation. The rhizospheric microbial community structure changed significantly under the PGPR of root irrigation. The dominant phyla, except Actinomycetota, in the soil samples had the greatest correlation with phosphorus solubilization and the auxin production of PGPR strains. The branch number, leaf number, and chlorophyllcontent had a positive correlation with the phosphorus solubilization and auxin production of PGPR strains and soil element contents. In conclusion, plant growth could be promoted by the root irrigation of PGPR to improve rhizospheric soil nutrients and the microenvironment, with modification of the rhizospheric soil microbial community. Plant growth could be promoted by the root irrigation of PGPR to improve rhizospheric soil nutrients and the microenvironment, with the modification of the rhizospheric soil microbial community. These data may help us to better understand the positive effects of PGPR on blueberry growth and the rhizosphere soil microenvironment, as well as provide a research basis for the subsequent development of a rhizosphere-promoting microbial fertilizer.

Biochemical and allelopathic features of Adonis vernalis, Allium ursinum, and Leucojum vernum in the M.M. Gryshko National Botanical Garden of the NAS of Ukraine

The article presents the results of a study on the content and dynamics of the accumulation of biogenic elements and brassinolides in plants of Adonis vernalis, Allium ursinum, and Leucojum vernum in Kyiv, Ukraine. Data is provided on allelopathic activity, content of macro- and microelements, phenolic compounds, and laccase activity in plants and the rhizosphere soil under the conditions of the M.M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (NBG). The plants from the collection of the NBG were used as objects of study in field experiments. The content of biogenic elements in plant tissues and soil was analyzed using an inductively coupled plasma spectrometer. The allelopathic analysis of soil was conducted using a direct bioassay method with Lepidium sativum seedlings as the test object. Phenolic compounds were extracted from the soil using the ion exchange (desorption) method. The content of brassinosteroids was measured spectrophotometrically at a wavelength of 450 nm. The content of laccase was measured spectrophotometrically at a wavelength of 530 nm.The results demonstrate that model plant species employ a wide range of physiological mechanisms throughout the vegetation period to enhance their resistance to abiotic factors. These mechanisms include maintaining potassium and calcium balance and utilizing hormonal compounds. Plants have been proven to have compensatory mechanisms in response to stress factors, substituting one biochemical marker of resistance with another. Both, brassinosteroids and silicon, contribute to the adaptive capacity of organisms.

A preliminary study on heavy metal monitoring in soil and guar (Cyamopsis tetragonoloba) biomass amended with sewage sludge.

Applying sewage sludge in agricultural soils is an interesting source of organic matter. This study aimed to monitor concentrations of heavy elements in soil and guar plants, which can pose a risk to the health of humans and animals if they enter the food chain through the soil-plant system. The experiment revealed that applying sludge increased the amount of organic matter, total nitrogen, potassium, and phosphorus in the soil. Additionally, the concentration of heavy metals such as Pb, Co, Cr, Ni, Cu, and Zn in all treatments remained below the permissible limits for soil. The highest plant height and plant dry weight were recorded in the sludge and sludge + fertilizer treatments. The dry weight of the guar varied from 629 g m-1 in the control treatment to 1050 g m-1 in the sludge + fertilizer plots. The use of sludge increased the accumulation of heavy metals in the above-ground parts of the guar plant compared to the control. However, the level of heavy metal remained within the normal range and below the toxic concentration. Our results also showed that the application of sludge along with fertilizer improved the quality of the guar forage by increasing the levels of crude protein, digestible dry matter and water-soluble carbohydrates. Overall, the results indicated that using sludge as organic fertilizer can improve soil properties, reduce the use of inorganic fertilizers, and decrease the harmful effects of heavy metals on the environment and health in the research area.

The influence of the environmental factors on the accumulation patterns of toxic elements in Plantago lanceolata sampled in the area under strong anthropopressure

The study aims to explore the environmental factors which activate accumulation abilities of Plantago lanceolata in the research area under strong anthropopressure resulting from the long-term pollution originating from copper mining-metallurgical activities in Southeastern Europe. Sampling was performed at the most endangered sites regarding its proximity to the major and/or secondary pollution sources, as well at the control site. The content of toxic elements (Al, Cu, Fe, Mn, Ni, Pb and Zn) was determined in the roots, leaves, stalks and flowers of P. lanceolata. The anthropogenic origin of environmental contamination was denoted through the high concentrations of Cu, Pb and Zn in the leaves of P. lanceolata, reaching toxic levels, combined with the enrichment of plant parts (Enrichment factor >2), especially with Cu (as well as with Al, Fe, Ni and Zn) in samples from the immediate proximity to the copper smelter or at the prevailing wind directions. Biomonitoring potential, assessed through the correlations between toxic element content, as well as the values of Enrichment factor, was indicated for roots (in the case of Cu), all the aboveground plant parts (Fe) and stalks (Zn). The results have shown that the contents of toxic elements in plant parts as well as phytoremediation of P. lanceolata were dependent on soil element content, soil physico-chemical properties and soil enzyme activities, which were regarded as the main environmental drivers affecting phytoremediation ability. The analysis of biological factors (bioconcentration, translocation and bioaccumulation factor) indicated exclusion strategy and possible usage of P. lanceolata in phytostabilization of Zn. The results indicated that the study area is 'environmental hotspot' with potential threat to human health due to the high levels of bioaccumulation of the investigated toxic elements in P. lanceolata parts.

Element accumulation by the holoparasitic species Cuscuta planiflora from serpentines in Bulgaria

AbstractThe holoparasitic species Cuscuta planiflora Ten. (Convolvulaceae) parasitizes the Ni hyperaccumulator Odontarrhena muralis (Waldst. &amp; Kit.) Endl. and a non‐hyperaccumulator, Sanguisorba minor Scop., in Bulgarian serpentine areas. This study investigated the host/parasite relationship to evaluate: (1) metal accumulation in different parts of the parasite and the host and (2) its potential threat to Ni phytomining/agromining by suppressing growth of the hyperaccumulator. Elemental concentrations in soil, shoots, leaves, and inflorescences of the two host plants, and in shoots and inflorescences of the parasite, were determined. Elemental concentrations of Ca, Mg, Fe, Ni, Cr, Co, Zn, Cu, Mn, Cd, and Pb were determined after microwave digestion using inductively coupled plasma—optical emission spectrometry (ICP‐OES) under optimal instrumental parameters. Individuals of hosts, both infected and non‐infected, differed in the concentrations of essential elements (P, K) and some micronutrients. Infected individuals of O. muralis showed lower Ni concentrations in shoots, leaves, and inflorescences compared to non‐infected ones. Sanguisorba minor is an excluder plant with low tissue Ni concentrations. The parasite had higher P and K, and lower Ca, Mg, Ni, Zn, Co, and Mn concentrations, than the host. The highest Ni concentration measured in the shoots of C. planiflora was 279 mg kg−1, whereas that from S. minor was 29.9 mg kg−1. Element transfer from host to parasite appeared element‐specific and after infection Ni concentrations in all organs and biomass of hosts were reduced. We conclude that infection by C. planiflora is a potential threat to use of O. muralis for Ni agromining.