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1.
The effect of natural and technogenic factors on the mobility and transformation of metal compounds was studied from an analysis of the fractional-group composition of Cu, Zn, and Pb compounds in the soils of areas adjacent to the Novocherkassk power station. Changes in the composition of Cu, Zn, and Pb compounds in the soils of technogenic landscapes were estimated. The effect of aerosol technogenic emissions on the mobility of metal compounds was revealed; a higher metal mobility was found in soils with low buffering capacity. Common and specific features of the formation of Cu, Zn, and Pb compounds in soils were determined. The role of individual soil components in the retention of metals in clean and contaminated soils was established.  相似文献   

2.
The content and isotope ratios of lead were studied in soils, street dust, and snow sampled in the Southeastern administrative district of Moscow. The relationships between the lead isotope ratios and the content of different lead compounds in soils were revealed. It was shown that isotope ratios for the total lead have low information values upon low levels of lead contamination. The contribution of technogenic lead compounds to the isotopic composition of lead increases in the following sequence: total lead < acid-soluble lead < mobile lead. The effect of emissions from thermal power stations and vehicles’ exhaust on the isotopic composition of lead in the street dust and soils was estimated.  相似文献   

3.
The transformation of technogenic compounds of nickel, copper, zinc, and lead entering the soil as nitrates and oxides has been studied in a model experiment. It has been shown that the results of the determination of the fractional composition of the heavy metals strongly depend on the fractionating method used. The fractional composition of heavy metals that entered the soil as the readily soluble compounds mainly depends on the affinity of ions with the reaction centers of the soil components. When soils are polluted by such weakly soluble compounds of heavy metals as oxides, their transformation and, consequently, the fractional composition formed are determined, in the first place, by the solubility of these compounds and only afterwards by the interaction of the products of the dissolution with the soil. The transformation of the technogenictechnogenic zinc and lead oxides in the soils is more complete than that of copper and nickel oxides. This leads to a strong increase in the portion of the residual fraction of these elements under fractionating. The 1 N nitric acid almost does not extract copper and nickel oxides from the soil. This can be a reason for the erroneous estimation of the extent of soil pollution.  相似文献   

4.
The total concentration and fractional composition of aluminum compounds were determined in soil solutions obtained using vacuum lysimeters from the main genetic horizons of peaty-podzolic-gleyic soils developed on binary deposits. The total concentration of aluminum in the brooks draining the area with a predominance of these soils was also estimated. The total aluminum concentration in the soil solutions reached the maximum values (0.079–0.092 mmol/l) in the Eih horizon and generally decreased down the profile. The aluminum in the soil solutions occurred in the form of monomeric inorganic and organic compounds and complexes with high-molecular-weight organic acids. The proportion of inorganic monomeric aluminum compounds in the solutions from the peaty-podzolic-gleyic soils increased compared to that in the podzolic soils; no aluminosilicate compounds were found. Aluminum arrived to the brooks draining the areas with the predominant peaty-podzolic-gleyic soils mainly from the above-moraine horizons, including the Eih, E, and Ecn. It was supposed that the removal of aluminum from these soils exceeded that from the podzolic soils.  相似文献   

5.
Nodules (nodules) forming in the chernozem-like soils of flat-bottomed closed depressions on the northern part of the Tambov Plain differ in their morphology and chemical composition as related to the degree of hydromorphism of these soils. The highest are the coefficients of Mn, P, and Fe accumulation in the nodules from these soils. The Fe to Mn ratio grows with the increasing degree of hydromorphism. Under surface moistening, the maximal amounts of mobile Mn and Fe compounds were extracted from the nodules of the most hydromorphic podzolic chernozem-like soils; under the ground moistening, their greatest amounts were extracted from the least hydromorphic soil—the weakly gley soil. In the first case, the content of organic phosphates in concretions amounted to 30–50%; in the second one, 2–3% of their total content. Under surface moistening, the proportion of active mineral phosphates becomes higher with the increasing hydromorphism: from 30 (podzolized soil) to 70% (gleyic podzolic soil). Under ground moistening, on the contrary, their proportion decreases from 70–89% in the weakly gley soil to 40–50% in the gley chernozem-like soil. The possibility to determine the degree of hydromorphism of chernozem-like soils based on the coefficients of bogging is shown. The expediency of using Schvertmann’s criterion in these studies is assessed.  相似文献   

6.
Tissues of Angiospermae (deciduous arborous and herbaceous plants) were found to take part in the formation of humus in the agrogray soils. The proportions of lignic phenol contents between the soils did not change neither upon their plowing, no their drainage. Within the catenas studied, the maximal accumulation of phenol compounds takes place in the soils of the mesodepressions with long-term reduction conditions and in the soils of the microdepressions with spring perched water on two levels. In the Fe-Mn nodules of the agrogray soils, lignin of higher plants was found. Its fractional composition was correlated with the predominant vegetation. With the increasing size of the nodules, the amount of products of lignin oxidation in the nodules decreased due to its mineralization. Drainage caused a deep transformation of lignin in the Fe-Mn nodules, especially in the coarse fractions of concretions. The mineralization of lignin aromatic compounds under aerobic conditions was accompanied by the significant increase in the share of phenol acids.  相似文献   

7.
An ordinary chernozem artificially contaminated with Zn and Pb salts and reclaimed by the addition of chalk and glauconite under pot experimental conditions has been analyzed. The fractional and group composition of the metal compounds in the soil extracts have been determined according to an original combined fractionation procedure. Coefficients characterizing the changes in the environmental status of the metals under the reclamation conditions have been proposed for describing the formation tendencies of the metal composition in the soils. These are the mobility coefficients (MCs) of the heavy metals (HMs) in the soils and the stability coefficients (SCs) of the soils for the HMs. They are calculated from the analysis of the fractional and group composition of the metal compounds. The MC characterizes the environmental vulnerability of soils to the impact of HMs; the SC characterizes the environmental sustainability of soils concerning the contamination with HMs. The obtained experimental data characterize the behavior features of Zn and Pb in the studied soils. An increase in the environmental hazard has been revealed at the contamination of soils with HMs, as well as its decrease at the application of the tested ameliorants. The participation of both strongly and loosely fixed HM fractions in the development of the HM mobility in the soils and the sustainability of the soils to their impact has been shown.  相似文献   

8.
The soil cover inside the walls of the New Jerusalem Monastery (in the city of Istra, Moscow region) has been completely transformed during the long history of anthropogenic loads on the local landscape. Specific anthropogenic soils have been formed from the technogenic deposits on the top and slopes of the monastery hill. These soils contain numerous artifacts; in their upper part, horizons with characteristic features of the modern humus-accumulative process have been developed. The major types of anthropogenic soils on the territory of the monastery—urbiagrostratozems, soddy urbistratozems, and soddy-calcareous urbistratified soils—have been described. The composition of technogenic deposits determines the shift of pH values towards the alkaline reaction, the high content of available phosphorus compounds, and the soil contamination with heavy metals. The post-alluvial gray-humus soils close in their morphology and chemical properties to the natural soils of the floodplain predominate in the soil cover of the park zone adjacent to the walls of the monastery in the Istra River valley.  相似文献   

9.
Eurasian Soil Science - A comparative analysis of the chemical composition and properties of water-soluble compounds of the soils on calcareous rocks, aboveground phytomass, and waters is performed...  相似文献   

10.
Specific features of organic matter, molecular composition and distribution of oxygen-containing nonspecific organic compounds (fatty acids, long-chain aliphatic alcohols, and ketones) were revealed in two peat soils on slopes of the Subpolar Urals: the eutrophic peat soil of the spring mire (Hemic Histosols) and the peat soil of a slope mire (Fibric Histosols). Compounds that can serve as molecular markers for some evolutionary stages of peats were determined for this area. Based on the data obtained, the most probable causes of differences in the composition of organic compounds in the peats studied were found to be the following: environmental conditions, water and mineral regime of bog, and differences in the composition of peat-forming plants.  相似文献   

11.
The relationship between organic P status of 4 soils, 20 microorganisms isolated from these soils (2 bacteria and 3 fungi for each soil) and 13 dominant plant species of typical natural ecosystems of these soils was evaluated. The soils used were represented by two pairs with different ratios of monoester and diester P, and of DNA and other diester P. A Dystric Podzoluvisol and an alpine Umbric Leptosol were characterized by a relatively high proportion of diester P including much DNA P, while a Calcic Chernozem and subalpine Umbric Leptosol had lower proportion of diesters containing relatively less DNA P. The proportions of P compounds in bacteria and plants were very similar on average, based on the monoester to diester P ratio and on the proportions of different diesters in alkaline extract, whereas fungi contained considerably higher proportions of monoesters and polyphosphates, and a higher proportion of phospholipids in the diester fraction. The results showed that the Porg composition of NaOH extracts from different soils was more similar to the composition of extracts from different groups of microorganisms. There was no clear correspondence between soil and microbial diester P proportion and composition. A high proportion of polyphosphate P including pyrophosphate P in soil extracts indicates a significant contribution of fungal P compounds in the soil while the monoester to diester P ratio, and DNA to non-DNA P ratio should be used with caution to interpret the origins of soil Porg. The relative contributions of microorganisms and plants to monoester and diester P in soils is only partially understood.  相似文献   

12.
The differentiation of the soils under study in terms of the bulk chemical composition of the solid phase was mainly manifested along the profile and decreased with depth, because it was primarily ensured by the different aspects of the biogenic accumulative processes. The bulk composition parameters of the solid phase were of higher information value for determining the type of soil horizon, and the composition of the water-soluble compounds (in water extracts and natural soil solutions) reflected the features characteristic of the soil type.  相似文献   

13.
Microbial composition is known, on similar soil types, to vary based on differing organic matter inputs, or stand composition. Fine-textured luvisolic soils, which dominate the upland boreal forests of Western Canada, support a canopy cover of aspen (Populus tremuloides Michx.), white spruce (Picea glauca (Moench) Voss) or a mixture of the two. These soils then reflect different belowground biogeochemical processing of organic matter. Novel, anthropogenic soils formed from a combination of peat litter and fine textured mineral soil, are now also a part of the landscape in the western boreal. This study set out to determine if a simple labeled compound (13C glucose) was processed differently by soils from the two dominant stand types (aspen and spruce) and from an anthropogenic (newly reclaimed) site. Results indicate that while all three soils rapidly incorporated and respired the labeled carbon, each maintained a distinct microbial community structure (as evidenced by phospholipid fatty acid analysis) throughout the 300 hour experiment. Therefore soils with different microbial communities from varied organic matter inputs decompose organic carbon by different processes, even in the case of simple labile compounds.  相似文献   

14.
Makarov  M. I.  Buzin  I. S.  Tiunov  A. V.  Malysheva  T. I.  Kadulin  M. S.  Koroleva  N. E. 《Eurasian Soil Science》2019,52(10):1195-1206
Eurasian Soil Science - The isotopic composition of nitrogen in soils and plants may be an indicator of transformation of its compounds and sources of N nutrition of plants. Natural 15N abundance...  相似文献   

15.
Natural and technogenic compounds of heavy metals in soils   总被引:1,自引:0,他引:1  
The existing geological classification of heavy metals (HMs) is not suitable for their characterization in soils. The carriers of HMs in soils differ from those in the lithosphere. These are clay minerals; iron oxides, whose composition varies between the background and urban soils; various manganese oxides; and different groups of organic substances. The mineral composition of HM carriers can vary significantly. The main iron oxides are ferrihydrite, goethite, feroxyhyte, and lepidocrocite in the background soils and technogenic magnetite in the urban soils. The different structures of manganese oxides determine their affinity for specific HMs. Metallic iron and green rust are very efficient in artificial geochemical barriers, although they act as strong reducers there. HM compounds strongly vary in soils because of the unstable conditions.  相似文献   

16.
The contents and distribution of water-soluble, exchangeable, and nonexchangeable forms of potassium have been studied in the profiles of sandy gleyic soddy-podzolic soils under forest, intensively used cropland, extensively used cropland, and a 20-year-old fallow. It is shown that soil cultivation leads to a rise in the concentration of mobile potassium compounds. The ratio between nonexchangeable and exchangeable forms of potassium also changes in the cultivated soil. Under the fallow, the restoration of this ratio to the values typical of the soil under natural forest cenoses takes place. Data on the mineralogical composition of the clay and colloidal fractions in the virgin and cultivated soils are presented.  相似文献   

17.
The content and composition of the lignin phenols in plants and soils of vertical natural zones were studied in the Northern Caucasus region and Northwestern Tien Shan. Three types of lignin transformation were revealed: steppe, forest, and meadow ones. It was shown that the degree of oxidation of the biopolymer during the transformation of organic matter increased when going from the living plant tissues to humic acids in surface and buried soils. The portion of lignin fragments remained unchanged during the biopolymer transformation in the following series: plant tissues-falloff-litter-soil-humic acids-buried humic acids. It was also shown that the biochemical composition of the plants had a decisive effect on the structure of the humic acids in the soils. The quantitative analysis of the lignin phenols and the 13C NMR spectroscopy proved that the lignin in higher plants was involved in the formation of specific compounds of soil humus, including aliphatic and aromatic molecular fragments. The first analysis of the lignin content and composition in buried soils of different ages was performed, and an increase in the degree of oxidation of the lignin structures was revealed in the soil chronoseries. It was proposed to use the proportions of lignin phenols in surface and buried soils as diagnostic criteria of the vegetation types in different epochs.  相似文献   

18.
Litter samples from peat podzolic (Stagnic Podzoluvisol) and soddy gley (Mollic Gleysol) soils differing in their chemical and physicochemical properties, geochemical conditions, and the character of soil microbial complexes were analyzed. The sampling was performed three times during the growing season: in May, August, and October. The contents of ammonium ions, soluble phenolic compounds, and flavans were determined in all the samples. The litters of the two soils differed in the contents of both ammonium ions and phenolic compounds. Distinct seasonal dynamics of ammonium and phenolic compounds were registered in the litter of the peat podzolic soil. The high negative correlation between the contents of ammonium ions and phenolic compounds was found for the samples collected in May.  相似文献   

19.
Differences in the chemical composition of soils developed from sorted sands of different origins are revealed. The iron-illuvial podzols on rich glaciofluvial and marine sands are characterized by well-pronounced Al-Fe-humus differentiation of the Si, Al, and Fe in the soil profile. These soils are relatively similar in their bulk elemental composition. The difference between them is seen in the degree of differentiation of the soil profiles; it is stronger in the soils developed from glaciofluvial deposits. This is particularly true with respect to the oxalate-soluble iron and aluminum hydroxides. The deposits derived from the red-colored Tersk sandstone and processed by the sea (in the coastal zone of the White Sea) have the poorest chemical composition. In the soils developed from them, the differentiation of oxalate-soluble compounds is slightly pronounced (for Fe) or completely absent (for Si and Al). These soils can be classified as podzolized ferruginous red-colored psammozems (within the order of poorly developed soils) with the following horizons: O-Ce-Cf-C. The Ce horizon has the features of podzolization, and the Cf horizon has some features attesting to the illuvial accumulation of Fe. The profile of these soils inherits a reddish tint from the parent material.  相似文献   

20.
The influence of different agricultural treatments on the contents of Cd, Zn, and Co in the organic matter and humic acids of soddy-podzolic and dark gray forest soils was studied in long-term field experiments. The use of gel chromatography proved the complicated molecular-weight composition of the humic acids in all the studied soils. The contents of heavy metals and their distribution by the molecular-weight fractions of humic acids were determined in the experimental soils and in the virgin podzolic soils. The complex nature of organomineral compounds of Cd and Zn with humic acids was shown by means of gel filtration. The thermodynamic stability of the organomineral complexes increased with the increasing weight of the initial molecular-weight fractions of humic acids.  相似文献   

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