Trace Elements In Soils Research Articles

Metalliferous habitats and seed microbes affect the seed morphology and reproductive strategy of Arabidopsis halleri.

Plant reproduction in metalliferous habitats is challenged by elevated concentrations of metal trace elements in soil. As part of their survival strategy, metal-tolerant plants have adjusted reproductive traits, including seed morphology, dormancy, and germination rate. These traits are particularly relevant, yet poorly understood, in metal hyperaccumulators that are promising candidates for phytoremediation. We assessed seed shape characteristics, dormancy, and germination rate in the hyperaccumulating model species Arabidopsis halleri. Seed morphological parameters were evaluated using seeds collected from two metalliferous and two non-metalliferous sites (~ 1000 seeds per location). We also addressed the potential influence of seed surface-associated microbes and endophytic fungi on germination success. Seeds from non-metallicolous populations were on average 18% bigger than those from metal-contaminated post-mining sites, which contrasts the general expectation about reproductive parts in metallicolous plants. Irrespective of their origin, surface-sterilized seeds had up to ~ 20% higher germination rates and germinated earlier than non-sterilized seeds, hinting at a negative effect of seed-associated microbial communities. Surface sterilization also facilitated the emergence of an endophytic fungus (Aspergillus niger) that is a known seed-borne pathogen. Interestingly, A. niger actually promoted germination in surface-sterilized seeds from some locations. Despite species-wide metal tolerance in A. halleri, metalliferous conditions seem to differently affect reproductive traits compared to non-metalliferous environments (e.g., smaller seeds). Yet, higher germination rates in these populations hint at the potential of A. halleri to successfully colonize post-mining habitats. This process is modulated by site-specific interactions with seed microbiota.

Concentration, Sources, and Associated Risks of Trace Elements in the Surface Soil of Kathmandu Valley, Nepal

Concentration, Sources, and Associated Risks of Trace Elements in the Surface Soil of Kathmandu Valley, Nepal

Mineral Fertilization and Maize Cultivation as Factors Which Determine the Content of Trace Elements in Soil

This study has been carried out in order to determine the effect of increasingly intensive fertilization with potassium, applied in combination with nitrogen, on the content of trace elements in soil after the harvest of maize (Zea mays L.). The soil content of trace elements depended on the fertilization with potassium and nitrogen. Potassium fertilization had a stronger effect on the content of trace elements in the pots fertilized with the lower nitrogen dose (130 mg N kg−1 of soil). The increasing doses of potassium led to a higher soil content of zinc (Zn), and especially of nickel (Ni). The impact of potassium fertilization on the content of the remaining trace elements in the soil was less unambiguous, and depended on the dose of potassium and nitrogen fertilization. Nitrogen fertilization resulted in a higher soil content of manganese (Mn), chromium (Cr), nickel (Ni) and cadmium (Cd), as well as a decreased soil content of lead (Pb). It needs to be underlined that changes in the soil content of Ni, Cd, and Pb, effected by nitrogen fertilization, were larger than in the cases of the other trace elements. The influence of potassium and nitrogen fertilization did not result in exceeding the current threshold amounts of trace elements set for agriculturally used soil. An increase in the contents of some trace elements in soil is beneficial from an agricultural point of view. Some of these elements are necessary for the correct growth and development of arable plants.

The effect of resource-saving tillage technologies on the mobility, distribution and migration of trace elements in soil.

The influence of agricultural tillage technologies on the accumulation and distribution of trace elements in the soil is poorly studied. At the same time, intensive agriculture requires large amounts of fertilizers, growth stimulators, pesticides, and other substances, which can effect the ecological safety of the plant products and soil. This paper represents studying the effect of various agricultural techniques (including resource-saving technologies) on the mobility and profile distribution of Pb, Zn, and Cu in Haplic Chernozem. No significant influence of resource-saving tillage technologies was found on the total Pb content. Contrary, the resource-saving tillage technologies was observed to promote the growth of the total Zn and Cu content depending on the cultivation method (by 26% Zn, 34% Cu at minimal tillage, and 28% for both elements using No-till in Ap horizon). Amongst different applied agrotechnologies, there was no influence found on the profile distribution of total elements content. Only two horizons showed the total Pb content accumulation: biogenic (Ap-A) and carbonate (BC-C) horizon. In contrast, the only biogenic accumulation for Zn was determined. Copper characterizes by even distribution over the soil profile. The use of resource-saving agricultural technologies increases exchangeable fraction of Zn, Pb and Cu in soil almost by 1.5-2.0 times in the Ap horizon compared to moldboard ploughing. Despite the increase in the exchangeable fraction of Zn and Cu, this amount of micronutrients is not enough for adequate plant nutrition. The use of various agricultural technologies at Haplic Chernozem led to changes in the distribution of studied elements' exchangeable fraction over the soil profile. The study results suggested a need to increase the amount of Cu and Zn fertilizers applied to the soil with resource-saving cultivation technologies.

Speciation of soil trace elements in different fumigated soils#

AbstractBackgroundSoil fumigation is widely used as an effective way to control soil‐borne diseases and increase crop yield. Fumigants may also affect the bioavailability and mobility of soil trace elements (STEs) due to the inhibitory and biocidal effects of soil microorganisms.AimsQuantification of STEs fractions after fumigation would help us in understanding the role of fumigants on soil environment and provide valuable evidence on the explanation of the “fertilizer effect” of soil fumigants. The overall objective was to quantify the effects of soil fumigation on three main chemical fractions of nine STEs.MethodsEffects of chloropicrin (PIC), dimethyl disulfide (DMDS), dazomet (DZ) on STEs were studied in three soils with standard and high dosages of fumigants. STEs fractions were detected using a modified Community Bureau of Reference three‐stage sequential extraction procedure.ResultsResults were evident in three farmland soils: (1) Among the nine elements, three fumigants had a significant impact on Mn and Co elements. Soils had a great complement to the bioavailable Mn and Co after fumigation. The content of Mn and Co in F1, the most available and transportable form for plants, significantly increased after fumigation with PIC, DMDS, and DZ. (2) Soil fumigation has an impact on Mn, Co, and other trace elements due to the process of Mn oxidation changed.ConclusionsOur study suggested that the complement of bioavailable Mn and Co could be an important factor to promote plant growth and increase crop yield after soil fumigation.

Risk assessment of trace elements accumulation in soil-herbage systems at varied elevation in subalpine grassland of northern Tibet Plateau.

Ecological environment of remote grassland has become a problem in many countries due to mining, tourism, grazing, and other human activities. In this study, a total of 15 pairs of soil-herbage samples were collected in the northeast of the Tibet Plateau to study the relationship between physicochemical properties and content of trace elements in soils at different elevation, and to examine the accumulation and fractionation of heavy metals in soil-herbage systems. In addition, the ecological risk of the subalpine grassland was also assessed. The average concentrations of Hg, As, Cu, Zn, Pb, Cd, Cr, and Mn in soil were higher than their background values of Gansu soil, but the average concentrations of these heavy metals in herbage satisfied Hygienical Standard for Feeds. The speciation analysis of heavy metals in soil indicated that the exchangeable content of heavy metal was very low, except Pb, Cd, and Mn. There was a linear relationship between pH, CaCO3, total phosphorus (TP), organic matter (OM), concentrations of Hg, As, Zn, Pb, Cr, and Mn in soils, dry weight of herbage, and elevation, while there was a quadratic curve trend between Cu, Cd in soils, and elevation. The results of risk assessment showed that there was no obvious ecological risk in the study area.

Study of Hematological Characteristics and Mineral Metabolism of Moscow Black Chickens in the Process of Acclimatization in the Astrakhan Region

The study of indicators characterizing the processes associated with the acclimatization of birds in new biogeochemical conditions is of interest in connection with the prospects of the poultry industry in the Astrakhan Region, where the lack of important trace elements in soils and plant feeds: Se, I, Co, is observed. In the presented study, the main hematological and biochemical parameters of blood and mineral metabolism were determined in 2 groups of chickens of the Moscow black breed: imported to the Astrakhan Region from Moscow and kept in the Moscow Region. The analyses revealed strong differences (P<0.01) in indicators of two groups. The acclimatized birds were characterized by low levels of red blood cells and hemoglobin in the blood, as well as a higher content of white blood cells than in the second group. The chickens had impaired lipid and protein metabolism. A 71.3% increase in the level of total sugar most likely indicated a stress state of birds. Compared with the chickens in the Moscow Region, the level of calcium in their blood was 32.4% lower, phosphorus – 12.9%. To a large extent, a decrease in the levels of iodine and selenium – by 5.3 and 5.2 times, respectively, was observed. Thus, in the absence of external changes, acclimatized chickens are subject to a latent form of combined I- and Se-hypomicroelementosis. At the same time, a drop in egg productivity by 19% is the recorded fact. The necessity to adapt to the new climatic conditions of the Lower Volga region for birds, combined with a lack of important trace elements, can cause increased oxidative stress in acclimatized birds. Based on the results of the study, the use of feed additives that make up for the deficiency of necessary trace elements is recommended.

Soil and Leaf Mineral Element Contents in Mediterranean Vineyards: Bioaccumulation and Potential Soil Pollution

The study reported here concerns the geochemical distributions of macro- and trace elements (including potentially toxic elements, PTEs) in the vineyard soils of Alcubillas, which is one of the oldest, albeit not world-renowned, wine-growing areas in La Mancha (Central Spain). Soil and leaf samples were analyzed by X-ray fluorescence spectrometry to ascertain the levels of various elements in the soil and the plant. The potential toxicity of the elements was assessed with regard to the development of the vineyard. Despite the fact that fertilizers and pesticides are employed in the vineyards in this area, the results showed that the levels of trace elements in the soil samples did not exceed the reference values according the pedogeochemical values for the region and Spain. This finding suggests that the study area is not polluted, and therefore, there are hardly any traces of anthropogenic contamination. The Biological Absorption Coefficient (BAC) was calculated to assess the assimilation of various elements from the soil to the leaves, and differences were found in the element absorption capacity of the vines. Some elements were not taken up by Vitis vinifera despite elements like Zr and Rb being present in relatively high concentrations in the soil. The production in these soils does not represent a threat to human health or the ecosystem, because the farmers in this area are extremely careful to preserve the environment and they only farm to achieve moderate yields of grapes per hectare.

Monitoring of the content of sulphur and trace elements in soils of the Central Chernozem Region of Russia

Monitoring of the content of sulphur and trace elements in soils of the Central Chernozem Region of Russia

A laboratory preparation procedure for studying bioaccumulation of U and its subcellular form in earthworms (Diplocardia spp.)

Uranium (U) is a ubiquitous trace element in soils. With increasing in application of U in nuclear energy and nuclear weapon, a large amount of U was dissipated into the environment including soil and water. Earthworm may be an eco-indicator for U bioaccumulation, transformation and transport across the ecosystem. There have been a variety of methods preformed to assess the bioaccumulation of uranium in small organisms such as earthworms, including uranium speciation, subcellular separation, and total U accumulation. All methods require an initial grinding preparation process that allows for the further fractionation of metals and metalloids in earthworms. The slime like mucus that coats the body of a worm presents a challenge in the disintegration and dissolution of the worm body. In order to analyze U subcellular forms, we developed a reliable and effective procedure to grind the worm body into a uniform fine suspension. We conducted a comparative study of disintegration of worms with 3 grinding techniques (agate mortar, liquid nitrogen freezing then agate mortar, and direct sonication) that would assist U subcellular analyses and bioaccumulation. The essences of this new development was as follows:•A scheme for preparation of earthworm samples for investigation of subcellular U forms in earthworms from U.S. army weapon test range soil with various U forms.•The direct sonication of earthworms was found to be the most proficient process in achieving the best preparation for U subcellular analyses with the high precision.

Geochemical and Environmental Assessment of Potential Effects of Trace Elements in Soils, Water, and Sediments Around Abandoned Mining Sites in the Northern Iberian Peninsula (NW Spain)

Geochemical and Environmental Assessment of Potential Effects of Trace Elements in Soils, Water, and Sediments Around Abandoned Mining Sites in the Northern Iberian Peninsula (NW Spain)

Femtosecond laser-induced breakdown spectroscopy by multidimensional plasma grating

The multi-dimensional-plasma-grating-induced spectroscopy (MIBS) technique that uses a 2D plasma grating formed by the interaction of three filaments to ablate the sample can achieve better detection of trace elements in soil.

Trace Elements in Agricultural Soils of Saanich Peninsula, Vancouver Island: Concentrations Trend Over Time, Mobility in Soils and Their Sources

Trace Elements in Agricultural Soils of Saanich Peninsula, Vancouver Island: Concentrations Trend Over Time, Mobility in Soils and Their Sources

Distribution Characteristics, Risk Assessment and Source Analysis of Trace Elements in Surface Sediments and Near Lakeshore Soils of Ranwu Lake in Tibet, China

Distribution Characteristics, Risk Assessment and Source Analysis of Trace Elements in Surface Sediments and Near Lakeshore Soils of Ranwu Lake in Tibet, China

Risk Assessment and Possible Sources of Trace Elements in Sediments and Near Lakeshore Soils of Ranwu Lake in Tibet, China

Risk Assessment and Possible Sources of Trace Elements in Sediments and Near Lakeshore Soils of Ranwu Lake in Tibet, China

Distribution of Cu, Ni, Zn, Mn, Cr, Cd, Pb, Co, Mo, As in alluvial soils of floodplain landscapes of the Sozh river basin

The studies were carried out in the western part of the Bryansk Region in the landscapes of the Sozh River basin (Iput’ River, tributary of the 1st order, south of the village of Perevoz; River Besed', tributary of the 1st order, northwest of the village of Baturovka; River Unecha, tributary 2nd order, west of the village of Lopatny). The aim of this work is to study the features of the vertical and horizontal distribution of the gross content of Cu, Ni, Zn, Mn, Cr, Cd, Pb, Co, Mo, As in the alluvial soils of floodplain landscapes. The selection of soil samples for the determination of the gross content of trace elements was carried out in subsystems of the floodplain landscape, different in geomorphology and hydrology, by the method of soil springs. Each key soil plot was a full-profile soil pit and four reconnaissance pits. Samples were taken from the walls of the cuts every 5 cm, mixed and averaged by the quartering method. The gross content of trace elements was determined by the atomic absorption method, after preliminary decomposition of the samples with a mixture of concentrated nitric and hydrofluoric acids using a microwave system. Variations in the content of trace elements in the layers of alluvial soils were assessed using the coefficient of variation. To characterize the degree of concentration or dispersion of trace elements in soils, the concentration clarke was calculated. As a result of the research, it was found that the vertical distribution of trace elements in the 0–20 cm layer is determined by their chemical properties and the genesis of the soils of the floodplain subsystems, and can be uniform, decreasing/increasing with depth or with concentration in separate layers. Clarke concentrations of microelements and their content increase in the direction from the riverbed to the near-terrace subsystem of the floodplain. Concentrations of elements in the soils of floodplain landscapes do not exceed the clarke value. The exceptions are Cr, Zn and Cu in the soil of the near-terrace subsystem of the river Unecha, Cd – in the soil of the central subsystem of the river Besed’, as well as Cu and Cd – in the soil of the near-terrace subsystem of the river Besed’. An excess of the clarke value for some elements may indicate their anthropogenic origin.

Quantification of multiple soil trace elements by combining portable X-ray fluorescence and reflectance spectroscopy

Several combinations of proximal sensors, portable x-ray fluorescence spectroscopy (pXRF), visible-near-infrared spectroscopy (vis-NIR), and mid-infrared spectroscopy (MIR) are assessed to quantify multiple soil trace elements (TE) with reliable accuracy. A total 622 topsoil samples (0–20 cm depth) collected at regular 8 km spacing across southern New Zealand were analysed for TE concentrations by a reference laboratory method and scanned with pXRF, vis-NIR, and MIR. The laboratory results and spectral information were used to develop robust models that enable prediction for soil concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn). Chemometric approaches including spectral data fusion, partial least squares – support vector machine (PLS-SVM) model fusion, and model averaging were tested to obtain optimal quantitative TE predictions in the samples. Validation of PLS-SVM based models on held-out samples showed the combination of pXRF and MIR performed optimally for predicting As, Cr, and Pb concentrations with concordance correlation coefficient (CCC) of 0.97 and root mean square error (RMSE) of 0.57 mg As/kg, 1.14 mg Cr/kg, and 1.05 mg Pb/kg respectively. Fusion of pXRF and vis-NIR data performed optimally for quantifying Cu, Ni, and Zn concentrations with CCC of 0.98 and RMSE of 1.09 mg Cu/kg, 0.63 mg Ni/kg, and 3.90 mg Zn/kg respectively. For Cd and Hg, Granger-Ramanathan model averaging of outputs from PLS-SVM based pXRF, vis-NIR, and MIR models performed optimally with CCC > 0.80 and RMSE of 0.03 mg Cd/kg and 0.01 mg Hg/kg respectively. This study showed that quantitative prediction models for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn can be successfully implemented at local- and national-scale and for long-term monitoring of soil trace elements at concentrations below pXRF detection limits and with reduced matrix interference from organic matter than from individual techniques alone.

ICP-MS Measurement of Trace and Rare Earth Elements in Beach Placer-Deposit Soils of Odisha, East Coast of India, to Estimate Natural Enhancement of Elements in the Environment.

Inductively coupled plasma mass spectrometry (ICP-MS) has been used to measure the concentration of trace and rare earth elements (REEs) in soils. Geochemical certified reference materials such as JLk-1, JB-1, and JB-3 were used for the validation of the analytical method. The measured values were in good agreement with the certified values for all the elements and were within 10% analytical error. Beach placer deposits of soils mainly from Odisha, on the east coast of India, have been selected to study selected trace and rare earth elements (REEs), to estimate enrichment factor (EF) and geoaccumulation index (Igeo) in the natural environment. Enrichment factor (EF) and geoaccumulation index (Igeo) results showed that Cr, Mn, Fe, Co, Zn, Y, Zr, Cd and U were significantly enriched, and Th was extremely enriched. The total content of REEs (ƩREEs) ranged from 101.3 to 12,911.3 µg g−1, with an average 2431.1 µg g−1 which was higher than the average crustal value of ΣREEs. A high concentration of Th and light REEs were strongly correlated, which confirmed soil enrichment with monazite minerals. High ratios of light REEs (LREEs)/heavy REEs (HREEs) with a strong negative Eu anomaly revealed a felsic origin. The comparison of the chondrite normalized REE patterns of soil with hinterland rocks such as granite, charnockite, khondalite and migmatite suggested that enhancement of trace and REEs are of natural origin.

Sorption Processes in Soils and Sediments

Sorption processes at the mineral–water interface are fundamental to the chemical functioning of soils, and impact the biogeochemical cycling of both trace and major elements in soil and sediment environments [...]

Human Activity in Antarctica: Effects on Metallic Trace Elements (MTEs) in Plants and Soils.

Colobanthus quitensis (Kunt) is one of the two vascular plant species present in Antarctica and develops under severe environmental conditions, being found in both pristine and human-threatened environments. We determined the Cd, Cr, Cu, Mn, Ni, Pb, and Zn levels in C. quitensis roots, leaves, and soils of origin using flame atomic absorption spectroscopy. In January 2017, we collected samples from four geographical zones on the longitudinal gradient along which C. quitensis is distributed, starting from Punta Arenas (PAR) at the extreme south of mainland Chile and moving southwards to the Antarctic territory from King George Island (KGI) to Hannah Point Peninsula (PHA) and finally Lagotellerie Island (LAT). We used certified reference material to validate the plant tissues and soil samples we collected. The highest concentrations of metals that we measured in the soils and in the C. quitensis roots and leaves were in samples we collected at the KGI station, the zone with the greatest human activity. The lowest concentrations we measured were at the LAT station, an island with little human intervention and scarce fauna. The mean concentrations of metals in the roots and leaves of C. quitensis followed a similar order at all sampling locations: Mn > Zn > Cu > Ni > Pb > Cr > Cd. In contrast, in soil, they followed the following order: Mn > Zn > Cu > Cr > Pb > Ni > Cd. The concentration levels obtained for the different metals in the soil and plants tissue samples in this region of Antarctica indicated that the area was non-polluted. However, the metallic trace element (MTE) concentrations may be at an early stage of contamination, as described in other areas of the Antarctic, being a new threat to this continent.