Mobile Forms Of Metals Research Articles

ЭФФЕКТИВНОСТЬ ПРИМЕНЕНИЯ ОРГАНОМИНЕРАЛЬНОЙ СИСТЕМЫ УДОБРЕНИЙ С ЦЕЛЬЮ ИНАКТИВАЦИИ ТЯЖЕЛЫХ МЕТАЛЛОВ ПРИ ВЫРАЩИВАНИИ КАРТОФЕЛЯ В СТЕПНОЙ ЗОНЕ САМАРСКОГО ЗАВОЛЖЬЯ

The aim of the research is increasing the productivity of potatoes via the use of organic fertilizers. Research was carried out on crop rotation fields with potato plantations of Arnica and Arosa breeds. The distance between the ridges is 75 cm, the ridge height is 18-20 cm, and the distance between seats in a row is 24 cm. In the applied crop rotation, potato was planted on fallow steam. The object of study is the soil of the upper farm field (0-30 cm). The results of applying programmed soil fertilizers for potato plants consisting of background mineral fertilizers N120P150K300 and manure in doses of 20 t/ha and 60 t/ha for four experimental plots with an area of 210 ha are pre-sented. Determination of heavy metal content was performed within the certified laboratory of the Federal state Uni-versity «Station of agro-chemical service «Samara» by atomic absorption spectroscopy. Based on the results of heavy metals mobile forms in the soil, a concentration coefficient was calculated, which showed that the actual av-erage value exceeds the background level. The lead concentration coefficient amounting to 1.6 – indicates the ac-cumulation of the element on the research area. Organo-mineral fertilizer N120P150K300+manure 60 t / ha allows you to restore the balance of mould on the research ordinary Chernozem, get an increase in yield of 4.1-8.9 t / ha, has an effect on reducing the content of gross heavy metals in the soil: Cd – by 1.2-1.4 times; Cu – 1.1-1.2 times, Pb, Zn, Mn and Fe – 1.1 times compared to the control area. Within the experiment N120 P150K300 + manure 60 t / ha lead mobility reduces to 3.9%, copper, zinc, iron-less than by 1 %, cadmium mobility increases by 3.4-5.7 %.

Geochemical researches of the Marmarosh massif of the Ukrainian Carpathians

Formulation of the problem. The main focus of our research is on the geochemical composition of the growth areas of beech forests in the Marmarosh Massif of the Ukrainian Carpathians, or primeval forests, which are almost unaffected by human activity. Geochemical investigations of beech forests are especially important, since the question of chemical component of environmental objects (soils, vegetation) is the basis for determining the degree of territories transformation in time. The Carpathians belong to one of the most studied metallogenic provinces. The ore occurrence contains natural gold, silver and silver minerals (sulfates, sulfides, hydrosulfides) associated with pyrite, chalcopyrite, arsenopyrite, pyrrhotite, marcasite, hematite, galena, and other. It is important to determine the background content of chemical elements in soils, which will become the basis for geochemical searches and the determination of pollution - "reference point", which should be relied upon when conducting environmental and geochemical studies in the territory of beech virgin forests. The purpose of the article. The purpose of this work is to determine the background gross content of chemical elements (Mn, Ni, Co, Ti, V, Cr, Mo, W, Zr, Hf, Rb, Ta, Cu, Pb, Ag, Sb, Bi, Zn, Cd, Sn, Ge, Ga, Be, Sc, Ce, La, Y, Yb, Th, As, Ba, Li, P) and the main mobile forms of metals - Cu, Pb, Zn in soils of forest ecosystems of beech forests of the Marmarosh Massif; determination of biogeochemical features of the concentration of chemical elements by vegetation - beech leaves, Hypericum L., Achillea millefolium, Boletus edulis, which will become the basis for monitoring studies. Methods. Lithochemical, biogeochemical testing was carried out. The gross content of chemical elements (emission spectral analysis) and mobile forms of metals (atomic absorption analysis) was determined. Results. The authors calculated the background values of chemical elements content in the soils of forest ecosystems of beech protected areas of the Marmarosh Massif. In conducting lithochemical studies, chemical elements (gross content) – Co, Ni, V, Cu, Zn, Pb, P, Mn, Ti, whose contents are higher in soils, where carbonate rocks are soil-forming and in the absence of carbonates - Cr, Mo, have been established Zr, Sn, Be. La, Y, Yb, Ba, Li. The main moving forms of metals in soils (Cu, Pb, Zn) were determined and their coefficients of mobility were calculated, on the basis of which it was established that the mobility of metals in soils where soil-forming rocks are granite-gneisses and sandstones higher than in soil-soils is 3–10 times, in addition, the pH value of soils is a dominant factor in solving the migration or concentration of metals and the formation of secondary salt halos in the presence of ore. An analysis of the chemical composition of the indicator vegetation and its parts – Hypericum L, Achillea millefolium and Boletus edulis in the area of Mount Figura was performed. Boletus edulis, St. Hypericum L, wort stems and yarrow Achillea millefolium are identified as Cu, Zn concentrators. This distinction is important when conducting biogeochemical studies with a search purpose. Scientific novelty and practical significance. The results of the conducted researches showed that the regularities of distribution of chemical elements and their mobile forms in soils and vegetation in different parts of the Trans Carpathian forest ecosystems can be the basis for the exploration, forecasting the ecological status of the territories and, in general, ecological and geochemical monitoring.

ЭКОЛОГО-ТОКСИКОЛОГИЧЕСКАЯ ОЦЕНКА СОСТОЯНИЯ ПОЧВ РОСТОВСКОЙ ОБЛАСТИ ПО СОДЕРЖАНИЮ ТЯЖЕЛЫХ МЕТАЛЛОВ

Purpose: to determine the ecological and toxicological state of various types of chernozems in Rostov region by the content of mobile forms of heavy metals. Materials and methods. The studies were carried out on irrigated areas of Semikarakorsky, Matveevo-Kurgansky, Neklinovsky, Salsky, Veselovsky districts of Rostov region. The soils were sampled in layers of 0–20, 20–40 cm and analyzed using the method of measuring the mass fraction of mobile forms of metals by atomic absorption. Results. The content of mobile forms of the determined metals (zinc, lead, cadmium, nickel, copper) was not found to be higher than the maximum permissible concentration (MPC). The rows of the determined metals were constructed according to their share of the MPC in the 0–20 cm layer, which showed that cadmium (from 0.2 to 0.4 MPC), lead (from 0.05 to 0.12 MPC) and nickel (from 0.04 to 0.17 MPC) are closer to MPC in all chernozems of the studied regions of Rostov region. Pollutants were found in the chernozems of Salsk region in the smallest amount, except for copper (0.09 MPC). The content of copper in soils 0.04–0.35 mg/kg indicates its low and stable distribution in the studied soils, except for Veselovsky district, where the analysis showed values below the detection limit, which may indicate a lack of copper as a trace element. According to the soil grouping for ecological and toxicological assessment by the content of mobile forms of heavy metals, they belong to the 1st group, i.e. the soils contain pollutants below the MPC and are suitable for the cultivation of all agricultural crops. Conclusions. The ecological and toxicological state of soils of the surveyed areas by the content of mobile forms of zinc, lead, nickel, cadmium and copper is assessed as satisfactory.

Integral assessment of heavy metal pollution in Don River estuary soils

Based on the cumulative pollution index, spatial distribution maps were obtained to establish categories of soil pollution taking into account the total content of heavy metals and the mobile forms of metals in the Don River estuarine region. The objects of the study included samples of zonal soils (Chernozem) and intrazonal soils (Fluvisols) from monitoring plots. The total concentrations of Mn, Cr, Ni, Cu, Zn, Pb, and Cd in the soils were determined by X-ray fluorescent scanning spectrometer. Mobile heavy metals compounds were transferred to a solution by extraction of 1 N NH4Ac, pH 4.8. When calculating the total metal content, it was shown the studied soils had generally an acceptable pollution category but taking into account mobile forms the categories of soils contamination variate up acceptable to extremely dangerous. The most polluted sites are associated with the estuary of small rivers and the branches flowing into the Taganrog Bay, the territory of the Taganrog port and its terminals, and road bridges. In line with hight categories of pollution, the use of the soils for cropping should be limited, and the cultivation of concentrator plants is excluded.

The effect of selected acidic or alkaline chemical agents amendment on leachability of selected heavy metals from sewage sludge

The aim of the study was to evaluate the effect of acidic (Fenton's reagent, peracetic acid) or alkaline (CaO) chemical agents amendment on chemical forms of Pb, Ni, and Cd in sewage sludge. The dose of Fenton's reagent was as follows: Fe2+=1g·L−1, Fe2+/H2O2=1:100; stabilisation lasted for 2h. The dose of CaO was equal to 1g CaO·gd.m.−1. The dose of CH3COOOH was 2.5g·L−1. Total concentration of all metals in the digested sewage sludge was higher than in the soil and it did not meet Polish law requirements. Acidic chemical stabilisation of sludge did not significantly decrease total metal content in the sludge. Amendment of CaO decreased the content of Pb, Cd, and Ni in the sludge. Chemical fractions of heavy metals were identified in the sludge (exchangeable, carbonate bound, iron oxides bound, organic and residual). The results indicate that stabilisation of the sludge with Fenton's reagent and peracetic acid increased the exchangeable fraction of Pb, Cd, and Ni compared to the digested sludge, but it did not increase shares of mobile forms of metals considered as a total of I-st and II-nd fraction. Amendment of CaO increased percent share of examined metals in residual fraction. Not-mobile fractions of examined metals overweight the mobile ones in all sludge samples regardless of the treatment method.

Monitoring of heavy metal contamination of soil and plants (for example, <i>Potentilla tanacetifolia</i> Willd. ex Schlecht.) of natural ecosystems in Chita urban areas

The paper presents data on the content of gross and mobile forms of zinc, cadmium, lead and copper in the soils of Chita and its surroundings. The paper contains a comparative analysis of the accumulation (Kn) and movement (KP) coefficients of these microelements in organs ( Potentilla tanacetifolia Willd. ex Schlecht.), relative to their gross content and mobile forms in soils. The authors have revealed that soil samples of the studied sites contain unequal gross amount of heavy metals. In some points (6 and 3) the content of cadmium and zinc exceeded the Mac, that is why such soils have been attributed to heavily polluted. The index of biological activity on mobile forms of heavy metals in all sites significantly exceeded the same index on gross forms. It was found that Potentilla tanacetifolia are accumulators of heavy metal ions. Aboveground bodies accumulate and absorb cadmium and copper especially intensively, thus the content of mobile forms of these metals in the soil is insignificant. Excessive adsorption of trace elements in the phytomass of plants can be connected with surface contamination. According to the content of zinc and lead, the accumulation values in the organs of P. tanacetifolia were characterized by small coefficient values, against the background of their high concentration in the soil.

Detection and Evaluation of Anthropogenic Pollution on the Basis of Geochemical Study of the Interstitial Waters of Marine and Freshwater Sediments

The chemical composition of interstitial waters from several inland seas and or water system (NPWS) exposed to anthropogenic pollution was studied. The patterns of the distribution of pollution in the Dnieper–Bug Estuary, Gelendzhik Bay of the Black Sea and in the Alexandria’s Eastern Harbor of the Mediterranean Sea were found. Most of the contamination occurs in the upper layers of bottom sediments and near mouth zones. A significant role is played by secondary contamination related to the dissolution and accumulation of metals and nutrients in the interstitial water and their migration to the water column. The estuary factor of anthropogenic pollution takes center stage according to a factor analysis for the combined impacts of potentially mobile forms of metals in the Dnieper–Bug Estuary. Studies of the Lake Pyasino pollution near Noril’sk were carried out.

Reveal appraisement level of anthropogenic pollution on the basis of geochemistry studying the interstitial waters of marine and freshwater sediments

The chemical composition of interstitial waters from several of inland seas and NPWS, exposed to anthropogenic pollution. The regularities of distribution of pollution in the Dnieper-Bug estuary and Gelendzhik Bay of the Black sea in the Eastern Harbor of Alexandria Mediterranean Sea. Most of the contamination confines to the upper layers of sediments and near mouth zones. A significant role is played by secondary contamination related to the dissolution and accumulation of metals and nutrients in the interstitial water and their migration in the water column. When factor analysis for the aggregate impact of potentially mobile forms of metals in the Diepr-Bug estuary factor of anthropogenic pollution came in first place. Studies pollution in the Pjasino Lake near town Norilsk.

METALS FORMS DISTRIBUTION IN LAKES SEDIMENTS OF NATURAL AND URBAN AREAS OF THE REPUBLIC OF TATARSTAN

The paper contains the comparative assessment of content levels and the revealed patterns of total and mobile forms of metals (Cd, Pb, Co, Cu, Ni, Zn, Cr, Mn, Fe) distribution in the bottom sediments of natural (Volga-Kama Nature Reserve) and urbanized (Kazan) territories of the Republic of Tatarstan. The changes in absolute metals content in sediments of urban lakes, as well as their ratio, breaking the Oddo-Harkins rule, caused by the forms of their release to the aquatic environment from technogenic sources are shown. Environment reaction and particle size composition of sediments are the factors determining the mobility of cationogenic metals in water bodies of natural and urbanized areas. It was found that the active layer of sediments, in which processes of biogeochemical transformation of natural and technogenic metals compounds occur, is a surface layer with capacity up to 50 cm.

Radiation and Geochemical Assessment of the Soil State in the South of Tyumen Region

The article presents a study of the radiation and geochemical background state of soil in the south of Tyumen region. According to the obtained data it was revealed that within the study areas, the power values of gamma radiation exposure dose ranged from 6 to 12.5 mcR/h, due to the natural gamma background of the area. The research results of the soils radiation status have shown that the main contribution to the radiation activity of soils is made by the natural radionuclide potassium-40 and man-made strontium-90. Elevated concentration of strontium-90 was observed in grey forest soils and amounted to 102 Bq/kg. The study of soil radiation contamination in the “Tavda” explosion epicenter (Nizhnetavdinsky district) revealed the dynamics of migration of radionuclides along the soil profile, which takes place at a considerable depth (80–100cm). The maximum concentration of strontium-90 was observed in the area “South-200” at the soil layer of 10–20 cm depth and was 1680 Bq/kg. The presence of heavy metals mobile forms in the soils of the Tyumen region south is within the MPC. The article presents a mathematical processing of the obtained results.

Metal partitioning and availability in estuarine surface sediments: Changes promoted by feeding activity of Scrobicularia plana and Liza ramada

Several works have evidenced in the past the importance and influence of plants and terrestrial invertebrates in metal availability in soils and sediments through changes in metal speciation. In contrast, the impact of estuarine invertebrates and fishes in this process has been poorly explored. The partition of metals in estuarine surface sediments was studied in a controlled environment according to four operationally defined fractions. Sediments were analyzed before and after the passage through the gut of two detritivorous species. Scrobicularia plana feeds on the bottom and suspended sediment particles through the inhalant siphon. Liza ramada is an interface feeder, filtering the superficial layer of the sediment and suspended particles in the water column. Cd, Cu and Ni bound to carbonates increased in the pellets of S. plana, compared with the ingested sediment, as did exchangeable Zn. Similarly, Cd and Zn bound to carbonates have also increased in the pellets of L. ramada; on the contrary, a decrease of Ni was observable in the pellets of this fish. The outcome of the controlled experiments pointed to a potential increase in some metals' availability in the estuarine environment, as a result of the more mobile metal forms in the excreted fecal pellets. This draws the attention to a relevant impact of the trophic activity of both species, alongside with the potential enhancement brought to it by the bioturbation promoted by them, in the role that the estuary itself has as a contaminants' buffer.

Effect of attendant anions on zinc adsorption and transformation in chernozem

The effect of anions on the adsorption and mechanism of interaction of zinc cations with a solid soil phase was established. Acetic acid anions had the greatest influence on bond strength between metal and soil particle surfaces, while the effect of nitric acid anions was the lowest. The difference in amount of mobile forms of zinc extracted by the soil depends on the dose and form of the zinc. The influence of the attendant anions on the content of mobile metal forms in the soil decreases in the order: PO42−≈Cl−>NO3−>SO42−>СН3СОО−>О−.

Standards for the contents of heavy metals and metalloids in soils

In line with the present-day ecological and toxicological data obtained by Dutch ecologists, heavy metals/metalloids form the following succession according to their hazard degree in soils: Se > Tl > Sb > Cd > V > Hg > Ni > Cu > Cr > As > Ba. This sequence substantially differs from the succession of heavy elements presented in the general toxicological GOST (State Norms and Standards) 17.4.1.02-8, which considers As, Cd, Hg, Se, Pb, and Zn to be strongly hazardous elements, whereas Co, Ni, Mo, Sb, and Cr to be moderately hazardous. As compared to the general toxicological approach, the hazard of lead, zinc, and cobalt is lower in soils, and that of vanadium, antimony, and barium is higher. The new sequence also differs from that of the metal hazard in soils according to the Russian standard on the maximal permissible concentration of mobile metal forms (MPCmob): Cu > Ni > Co > Cr > Zn. Neither an MPCmob nor an APCmob has been adopted for strongly hazardous thallium, selenium, and vanadium in Russia. The content of heavy metals in contaminated soils is very unevenly studied: 11 of them, i.e., Cu, Zn, Pb, Ni, Cd, Cr, As, Mn, Co, Hg, and Se, are better known, while the rest, much worse, although there are dangerous elements (Ba, V, Tl) among them.

Electrochemical effects in rocks: petroleum exploration and engineering–geological applications

The use of electrochemical effects in petroleum exploration and engineering–geological applications is discussed with reference to the Zhirnovsky oil and gas field where mobile forms of metals are 1.5–2 times above the background. Electrochemical stiffening applied to Maastrichtian shales, which are sliding planes of landslides in the Lower Volga area, increased their stiffness by a factor of 2 or more.

Prospecting for oil and gas fields on the shelf by the geoelectrochemical methods of water layer investigation

Geoelectrochemical methods applied widely in prospecting for continental oil and gas fields [1‐3] are based on the study of a unique phenomenon established first by Russian researchers: nearly vertical jet dispersion halos of mobile forms of the occurrence of heavy metals (oil microcomponents) [1, 3]. The mechanism of the quasi-convective transfer of mobile metal forms by gas bubbles in the course of the formation of jet dispersion halos is substantiated in [4]. In contrast to common geochemical methods, the geoelectrochemical methods make it possible to carry out more detailed investigations owing to specific features of the jet dispersion halos (contrast anomalies of heavy metal concentrations were recorded above the oil and gas pools located at a depth of 1050‐3540 m [5]).

Bio-accumulation and distribution of heavy metals in black mustard (Brassica nigra Koch)

There has been carried out a comparative research, which to allow us to determine the quantities and the depots of accumulation of Pb, Cu, Zn and Cd in the vegetative and reproductive organs of Brassica nigra, as well as to identify the possibilities of growing on soils, contaminated by heavy metals and its use for the purposes of the phytoremeditation. Experiments have been implemented in field and in controlled conditions. B. nigra is tolerant towards the heavy metals and could be successfully grown in regions of low and moderate level of contamination with heavy metals, without lowering of the quantity and quality of the manufactured production. The depots for accumulation, in case it is being grown on contaminated soils without Cu follows the order: roots > fruit's shells > stems > seeds. In the case of its growing on non-contaminated soils the order roots > fruit's shells > seeds > stems preserves for the Pb, while the order for the Cu, Zn, and Cd is: fruit's shells > seeds > stems > roots. A relation is determined between the quantity of the total and the mobile forms of metals on one hand, and their total quantity in the plants in the field, as well as, in the pot experiments, on the other. A drastic exclusion is made by the Pb in the pot experiments, as its basic part is blocked in compounds that are hardly soluble. Its absorption by the plants is almost entirely blocked, which is almost a degree lower than that obtained in the field experiments and is commensurable with the results obtained in non-contaminated soils. Clarification of the reasons causing this effect requires additional examinations and above all, fractionation of the soil and determination of the forms and depots of localization of Pb compounds.

Transformations of pollutants in the river water-pore solution-solid phase of the bottom sediments system in small rivers (using the example of waterways in the Losinyi Ostrov (Elk Island) National Park)

The distribution of heavy metals has been examined in water and bottom sediments of small streams within the Losinyi Ostrov (Elk Island) National Park (Moscow) that are undergoing manmade impacts. We demonstrated that pollution caused by motor vehicles causes seasonal changes in the general composition of the river water and pore solutions in bottom sediments. The strongest pollution of water and sediments was found near the CMHW (Circum-Moscow Highway) (Zn, Pb, Cu). This is expressed in the growth of mobile forms of metals in sediments. We have shown, using Zn as an example, the pollution transformation in the snow-river water-suspension-bottom sediment system.

Assessment of single extractions for the determination of mobile forms of metals in highly polluted soils and sediments—Analytical and thermodynamic approaches

Highly polluted forest/tilled soils and stream sediments from a mining and smelting area were subjected to single-extraction procedures to determine the extractable contents of Cd, Cu, Pb, and Zn. The results obtained from four widely used operationally defined single extraction tests were compared: deionised water, 0.01 mol L −1 CaCl 2, 1 mol L −1 NH 4NO 3 and 0.005 mol L −1 DTPA. The analytical data were coupled with measurement of the pH and Eh in extracts, mineralogical investigations and thermodynamic modelling using the PHREEQC-2 code. The changes in the pH of the equilibrated suspensions significantly influenced the metal extractabilities, with higher values in the lower pH regions. Although the DTPA procedure generally extracted the highest amounts of metals, it was found to be unsuitable for highly organic acidic forest soils, where anionic metal–DTPA complexes are assumed to be re-adsorbed on the positively charged surfaces of soil organic matter and oxides. The NH 4NO 3 extraction was also unsuitable due to the high ionic strength (1 mol L −1), limiting the use of the thermodynamic speciation model and the formation of the Cu(NH 3) 2+ complex, leading to acidification of the suspension. 0.01 mol L −1 CaCl 2 can be proposed as the most appropriate extraction medium, suitable for speciation modelling and analytical determinations using ICP-techniques and having an ionic strength similar to that of the soil solution. The metals are present in free ionic forms or chlorocomplexes in the CaCl 2 extracts, preventing their re-adsorption on the positively charged surfaces of soil solids (organic matter, Fe- and Mn-oxides) in acidic and circum-neutral conditions.

Determining mobile forms of metals in soil by the use of the sorption-kinetic method

A kinetic model has been designed for considering sorption accumulation in mobile forms of metals from soil suspension by the use of filters with immobilized chelate groups. The advantages of the method were demonstrated for use in large-scale analysis during soil testing.

Use of sequential extraction to assess the influence of sewage sludge amendment on metal mobility in Chilean soils

In Chile, the increasing number of plants for the treatment of wastewater has brought about an increase in the generation of sludge. One way of sludge disposal is its application on land; this, however involves some problems, some of them being heavy metal accumulation and the increase in organic matter and other components from sewage sludge which may change the distribution and mobility of heavy metals. The purpose of the present study was to determine the effect of sewage sludge application on the distribution of Cr, Ni, Cu, Zn and Pb in agricultural soils in Chile. Three different soils, two Mollisols and one Alfisol, were sampled from an agricultural area in Central Chile. The soils were treated with sewage sludge at the rates of 0 and 30 ton ha(-1), and were incubated at 25 degrees C for 45 days. Before and after incubation, the soils were sequentially extracted to obtain labile (exchangeable and sodium acetate-soluble), potentially labile (soluble in moderately reducing conditions, K4P2O7-soluble and soluble in reducing conditions) and inert (soluble in strong acid oxidizing conditions) fractions. A two-level factored design was used to assess the effect of sludge application rate, incubation time and their interaction on the mobility of the elements under study. Among the metals determined in the sludge, zinc has the highest concentration. However, with the exception of Ni, the total content of metals was lower than the recommended limit values in sewage sludge as stated by Chilean regulations. Although 23% of zinc in sludge was in more mobile forms, the residual fraction of all metals was the predominant form in soils and sludge. The content of zinc only was significantly increased in two of the soils by sewage sludge application. On the other hand, with the exception of copper, the metals were redistributed in the first four fractions of amended soils. The effect of sludge application rate, incubation time and their interaction depended on the metal or soil type. In most cases an increase in more mobile forms of metals in soils was observed as the final effect.