Mobile Forms Of Zinc Research Articles

Enzymative activity of technogenic surface formations of Kuzbass

The coal mining is one of the leading industries in the global energy balance. Kuzbass is the main region of Russia that specializes in coal mining. About 60 % of the country's coal is mined there. Coal mining is carried out mainly by the open-pit method. As a result, some 178 thousand hectares ha of disturbed land are formed. Enzymatic activity is an indicator of soil self-repair. The aim of the work was to study the enzymatic activity of technogenic surface formations of the Kuzbass to assess their toxicity and further selection of destructor microorganisms, rhizobacteria and hyperaccumulator plants, which will be further used at the biological stage of recultivation. As objects of research, the samples of technogenic surface formations taken on the territory of the Barzassky and Mokhovsky coal dumps. Enzymatic activity of technogenic surface formations of dumps was: invertase – 2,24 and 2,12 mg of sucrose split 1 g soil in 1 h; nitrite reductase – 0,57 and 0,07 mg reduced NO2- per 1 g soil in 24 h; asparaginase – 71,22 and 60,63 mg NH3 per 1 g soil in 24 h, respectively. When studying the enzymatic activity, it was assumed that the native microflora uses low- and high-molecular hydrocarbons (alkanes, polycyclic aromatic hydrocarbons (PAH), etc.) as carbon sources. The content of mobile forms of heavy metals (HM) in the studied samples exceeds the maximum allowable concentration by 1,2-2,6 times. In the course of statistical analysis, it was revealed that the gross and mobile forms of zinc and copper are nitrite reductase inhibitors, the gross and mobile form of nickel is an asparaginase activator, in technogenic disturbed formations of the studied coal dumps. Nickel is also an invertase inhibitor in the Mokhovsky coal dump.

ТЯЖЕЛЫЕ МЕТАЛЛЫ В ПОЧВАХ И В РАСТЕНИЯХ ПШЕНИЦЫ В ЗОНЕ ВОЗДЕЙСТВИЯ ПРЕДПРИЯТИЯ ПО ПРОИЗВОДСТВУ СТРОИТЕЛЬНЫХ МАТЕРИАЛОВ

Studies of sod-podzolic soils of forest and agricultural lands in the zone of impact of the enterprise for the production of building materials have shown that gas and dust emissions significantly affect the content of heavy metals in soils. The assessment of the content of gross forms of heavy metals in sod-podzolic soils of forest and agricultural lands adjacent to the territory of JSC «Krasnoselskstroymaterialy» showed widespread soil contamination with cadmium, arsenic and zinc. Soil contamination of forest and agricultural lands with lead is fragmentary. The highest occurrence of samples with an excess of hygienic standards for soils of forest lands was established for gross forms of zinc, and for soils of agricultural lands - for gross forms of cadmium and arsenic. The assessment of mobile forms of metals revealed soil contamination mainly with zinc and lead. Soil contamination with cadmium is insignificant and is fragmentary. It should be noted that the sod-podzolic soils of agricultural lands in the north-eastern direction from the enterprise are characterized by a high level of contamination with mobile forms of zinc and lead. The studies did not reveal an excess of the maximum permissible safe levels of cadmium and lead content in wheat grain and straw, however, the maximum concentrations of these elements in plants of this crop were on average 25-60 % higher in some areas compared to those in control areas, which indicates the presence of local zones in which there is an increased accumulation of heavy metals in agricultural plants. In this regard, it is necessary to organize monitoring of the quality of crop production for the content of heavy metals in the zone of influence of JSC «Krasnoselskstroymaterialy».

Content of heavy metals (Zn, Pb, Cu and Cd) in peat and plants of cutover peatlands

Two peatlands in the central part of the Kirov region (Zengino and Karino) were investigated. During three field seasons, soil profiles were compiled and peat samples by layers were collected. The content of total and mobile forms of zinc, copper, lead and cadmium was determined by inversion voltammetry. The content of the studied elements does not exceed the average values for various soil types of the region. Development of the peatland led to a change in the content and redistribution of chemical elements in the newly formed profiles. The botanical composition of peat is substantially related to the content of chemical elements: the accumulation of metals in layers with prevalence of wood remains was revealed. Economic use leads to active mineralization of the top part of the remained peat mass. The profiles of developed peatlands are characterized by considerable fluctuations in the content of heavy metals both in different profiles and in different horizons of the same profile. Plants growing on dried peatlands accumulate low doses of the investigated metals that do not exceed standards of maximum allowance concentrations. Rosa majalis accumulate zinc, lead and cadmium in the least degree. The highest concentration of all four elements is found in the leaves of Salix caprea.

PECULIARITIES OF HEAVY METAL ACCUMULATION IN SOILS IN URBANIZED LANDSCAPES OF BROVARY TOWN

The regularities of heavy metals distribution in technogenically polluted soils of urbanized territories on the example of the town of Brovary of Kyiv region were analyzed. Physical and chemical properties of conditionally clean and technogenically polluted soils were determined. Regularities of the geochemical distribution of heavy metals in the soil cover of the town under the influence of industrial enterprises were studied. Due to the influence of the Brovary enterprises, heavy metals content is significantly increased in comparison with conditionally clean soils. Using geochemical criteria the technogenic associations of heavy metals in soils were determined. Technogenic associations of heavy metals in soils are represented by the following elements: copper > plumbum > zinc > cobalt > chrome > vanadium > molybdenum > manganese > nickel. The total content level of chemical elements compounds in soils of different zones of the town is heterogeneous. The maximum of the man-caused load was recorded in urban areas of the transport infrastructure zone and the zone of production and communal-warehouse facilities. Copper and plumbum are the main pollutants according to the indices of heavy metals content in soils of anthropogenic zones of the city. Mobile forms of zinc and nickel are the most dangerous soil pollutants at all functional zones of the Brovary. The ecological and geochemical estimation of the total pollution index using Yu.Ye. Saet methodology is performed. The value of this indicator of the soil surface layer in Brovary town (0-10 cm) ranges from 30 to 106, the average value is 65, which corresponds to the dangerous level of contamination of the soil cover. The zones of transport infrastructure and the zones of production and communal-warehouse facilities have high levels of pollution, and the permissible pollution level dominates in the residential zone. According to the concentration ratio of technogenic pollution, the Brovary town belongs to the dangerous category of soil pollution. The investigated soils of the town are characterized by lead geochemical specialization. High levels of zinc, manganese, cobalt and chromium were established. The main factors that influence the concentration levels and heavy metals migration in the town soils were analysed. The dependence of heavy metals content and industrial production objects (factors of anthropogenic load on the natural components of the urban environment) in Brovary was established.

REGIONAL FEATURES OF THE CONTENT OF ZINC IN THE SOIL, PRODUCTS OF PLANT AND ANIMAL ORIGIN (FOR THE EXAMPLE OF THE REPUBLIC OF TATARSTAN)

The paper presents the data of the regional characteristics of the zinc content in the soil, products of plant and animal origin in the territory of the Republic of Tatarstan. The soil on the territory of the republic is established to be characterized by low values of the gross content of zinc (from 53.6 to 67.7 mg / kg of dry soil) and mobile forms of zinc (from 9.75 to 12.4 mg / kg of dry soil). This demonstrates the deficiency of this important trace element in the soil. The zinc content in animal products from 20 to 89% less than the average for the reference data, in plant products - from 10% to 360%. The study of nutrition found that the share of diets with normal zinc content is in men - 27.5%, in women - 22.5%. The average value of zinc in the blood serum of the population living on the territory of the Republic of Tatarstan, was 490 ± 40.7 ug / l. This is below the norm. The deviations from the recommended values are observed in all groups, regardless of their level of physical activity. Zinc status of surveyed persons has been below the norm in 80% of cases.

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.

Chemical forms of zinc in light chestnut soil under mono- and multielement types of pollution

Chemical forms of zinc in light chestnut soil polluted by zinc, copper, cadmium, and lead, introduced separately or jointly, were studied. A change in the initial relations between the element forms was found for all types of pollution. An increase in pollution of any type led to the accumulation of the most mobile forms of zinc in the soil. It was revealed that ion exchange is of the greatest significance in the fixation of zinc in polluted soil.