


Vol 49, No 11 (2016)
- Year: 2016
- Articles: 11
- URL: https://journals.rcsi.science/1064-2293/issue/view/13737
Genesis and Geography of Soils
Cartographic analysis of the distribution of saline soils in Russia depending on some climatic parameters
Abstract
The subdistrict zoning map distinguishes 27 subjects of the Russian Federation, 109 municipal districts, and 142 districts and subdistricts along the latitude line at 53°44′ N in Russia. Among them, soil salinization is observed in 13 subjects of the Russian Federation, 39 municipal districts, and 41 districts and subdistricts. The total length of the transect is 6354 m. The relationship between the distribution of saline soils and climatic parameters has been analyzed in the districts and subdistricts of the subdistrict zoning map. Information about soil salinity has been borrowed from the Soil Salinization Map of Russia (2003) and some regional salinization maps (Khakassia, Barguzin Depression). Climate is the main factor affecting the distribution of soil salinity. Among the analyzed climatic parameters, the Ivanov wetting coefficient (WC) best describes the relationship between climate and soil salinity. The share of saline soils in a district is inversely proportional to the WC value. The degrees of drainage and dissection of the area limit the effect of climate on soil salinity. It is proposed to subdivide the relief into three groups depending on the degree of dissection in order to correct the calculations of relationship between WC and soil salinity. With consideration for relief features, the relationship between soil salinity and WC is represented by a segment of the coordinate plane with WC as the ordinate and the share of saline soils as the abscissa. The segment is limited by two lines corresponding to the maximum and minimum soil salinities at given WC values. The use of the limiting equations allows predicting, with a high probability, the presence and distribution area of saline soils at a given latitude at 0.85 ≥ WC ≥ 0.5.



Factors and mechanisms of soil salinization under vineyards of southern Taman
Abstract
The spatial distribution of saline soils under vineyards in the south of Taman Peninsular is discussed. The Paleogene–Neogene clays of the Komendantskaya Mount serve as the source of salts. Vineyards were planted on an inclined plain at the foot of this mount. At present, their state on salt-affected soils worsens. In the upper part of the plain, solonchakous or deep-solonchakous slightly saline and nonsaline (within the upper 2 m) dark quasigley vertic soils (Vertisols) are formed. The salts are of the sulfate–sodium composition. Their vertical distribution has an eluvial pattern with a quick rise in the salt content from the surface layer to the depth of 50–100 cm and with a gradual increase in the salt content in the deeper layers. The absence of chlorides in the soils of flat areas within the slope attests to the predominance of lateral leaching of salts down the slope over their vertical leaching in the soil profiles. In the lower part of the slope, soil salinization mainly takes place in the hollow crossing the plain and the vineyard from the north to the south. In the middle part of the slope, nonsaline (to a depth of 2 m) agrohumus quasigley soils (Haplic Chernozems (Clayic, Aric, Stagnic)) are formed. Slight chloride–sulfate sodium salinization is only seen in the soils of the hollow, which contain fine-crystalline gypsum in the solid phase and display the accumulation of sodium chlorides in the middle part of the soil profile (in the 60–150-cm-thick layer). Heavy loamy agrochernozems with migrational and segregational forms of carbonates (Haplic Chernozems (Loamic, Aric, Pachic) are developed in the lower part of the slope; they are nonsaline to the depth of 2.5 m. In the area of transition from the humusquasigley soils to chernozems, specific horizons are formed in the hollow at the depth of more than 250 cm. Their soil solutions contain sodium, calcium, and magnesium chlorides against the background of the presence of fine-crystalline gypsum in the solid phase, which is typical of secondary salinization.



Automated updating of medium-scale soil maps
Abstract
An approach towards an automated updating of medium-scale soil maps via imitation of traditional mapping technologies is suggested. It is based on formulation of the rules of mapping in the form of classification trees for separating different soil cover patterns and on creation of the maps of soil-forming factors with the use of satellite data. Algorithms for mapping alluvial soils (Fluvisols), eroded (abraded), and anthropogenically transformed soils are presented. This approach was tested for the southern (Trans-Oka) part of Moscow oblast. The model for an automated soil mapping was realized using ILWIS software. The polygons of alluvial soils were mapped with a higher accuracy via the automated separation of floodplains according to the digital terrain model. The total area of alluvial soils shown on the medium-scale soil map decreased from 373 to 340 km2. Calculations of slope angles according to digital terrain models allowed us to localize soil cover patterns with participation of eroded soils with a higher accuracy; their area decreased insignificantly: from 791 to 781 km2. Anthropogenically transformed soils of building areas were mapped for the territory of Moscow oblast on the basis of satellite data for the first time. Their areas were delineated taking into account land use types and comprised 551 km2, i.e., 15.4% of the total area (3570 km2) of the Trans-Oka part of Moscow oblast.



Soil Physics
Microtomographic analysis of pore space in a virgin soddy-podzolic soil
Abstract
The method of X-ray microtomography was applied to study pore space of a virgin soddy-podzolic soil at the natural soil water content. The morphometric parameters of the pores of more than 100 μm in diameter were determined in the vertically oriented undisturbed soil monoliths (d = 3 cm, h = 3–4 cm) from the genetic horizons of the most differentiated part of the soil profile (the AY, AEL, EL, BEL, BT1, and BТ2 horizons). A tendency for the horizontal orientation of these pores was found in all the horizons, except for the humus (AY) horizon. Isolated vesicular pores of different sizes were abundant in the eluvial part of the profile. Numerous recent and relict phytogenic channels were found in the intraped mass of the BT2 horizon. Differently directed interfaces of structural units in the soil horizons were visualized. Cluster analysis was applied to estimate differences between the genetic horizons with respect to their textures, aggregate sizes, and shapes of pores as seen in vertical two-dimensional X-ray images.



Application of the CIE-L*a*b* system to characterize soil color
Abstract
Identification and classification of many soils are based on their color characteristics. The main soil pigments are humus providing a dark color to soil, as well as hematite αFe2O3 and other Fe(III) (hydr)oxides coloring the soil in red and yellow. The soil classification is possible only upon the quantitative color assessment, the CIE-L*a*b* system being the most convenient, as it represents a versatile color space in Cartesian coordinates. The indices of lightness L*, redness a*, and yellowness b* may serve as quantitative characteristics of soils in tundra and taiga zones. The difference in redness a* and yellowness b* may be used in identifying the type of predominating Fe-pigment in soils. The humus content may be determined according to the soil lightness, and the accuracy in its quantitative determination increases when the humus type is considered, as the humate humus is darker than the fulvate humus.



Agricultural Chemistry
Humus and nitrogen in soddy-podzolic soils of different agricultural lands in Perm region
Abstract
Heavy loamy soddy-podzolic soils (Eutric Albic Retisols (Abruptic, Loamic, Cutanic)) under a mixed forest, a grass–herb meadow, a perennial legume crop (fodder galega, Galéga orientalis), and an eightcourse crop rotation (treatment without fertilization) have been characterized by the main fertility parameters. Differences have been revealed in the contents of humus and essential nutrients in the 0- to 20- and 20- to 40-cm layers of soils of the studied agricultural lands. The medium acid reaction and the high content of ash elements and nitrogen in stubble–root residues of legume grasses favor the accumulation of humic acids in the humus of soil under fodder galega; the CHA/CFA ratio is 0.95 in the 0- to 20-cm layer and 0.81 in the 20- to 40-cm layer (under forest, 0.61 and 0.41, respectively). The nitrogen pool in the upper horizon of the studied soddy-podzolic soil includes 61–76% nonhydrolyzable nitrogen and 17–25% difficultly hydrolyzable nitrogen. The content of easily hydrolyzable nitrogen varies depending on the type of agricultural land from 6% in the soil under mixed forest to 10% under crop rotation; the content of mineral nitrogen varies from 0.9 to 1.9%, respectively. The long-term use of plowland in crop rotation and the cultivation of perennial legume crop have increased the content of hydrolyzable nitrogen forms but have not changed the proportions of nitrogen fractions characteristic of this soil type.



The influence of spruce on acidity and nutrient content in soils of Northern Taiga dwarf shrub–green moss spruce forests
Abstract
Presently, among the works considering the influence of forest trees on soil properties, the idea that spruce (Picea abies) promotes the acidification of soils predominates. The aim of this work is to assess the effects of spruce trees of different ages and Kraft classes on the acidity and content of available nutrient compounds in the soils under boreal dwarf shrub–green moss spruce forests by the example of forest soils in the Kola Peninsula. The soils are typical iron-illuvial podzols (Albic Rustic Podzols (Arenic)). Three probable ways of developing soils under spruce forests with the moss–dwarf shrub ground cover are considered. The soils under windfall–soil complexes of flat mesodepressions present the initial status. The acidity of organic soil horizons from the initial stage of mesodepression overgrowth to the formation of adult trees changed nonlinearly: the soil acidity reached its maximum under the 30–40-year-old trees and decreased under the trees older than 100 years. The contents of nitrogen and available nutrients increased. The acidity of the mineral soil horizons under the trees at the ages of 110–135 and 190–220 years was comparable, but higher than that under the 30–40-year-old trees. The differences in the strength and trends of the trees’ effect on the soils are explained by the age of spruce trees and their belonging to different Kraft classes.



Degradation, Rehabilitation, and Conservation of Soils
Cadastral valuation of lands polluted with radionuclides
Abstract
The major method to correct the cadastral value of land for contamination with radionuclides is to reduce it by the sum of expenses necessary for land remediation and for special measures ensuring the obtaining of agricultural and forestry products satisfying safety norms. Lands contaminated with radionuclides and used in agriculture and forestry are often removed from the system of land taxation. In this case, their cadastral value becomes an excessive element of the state cadaster of real estate. An approach toward cadastral valuation of such lands suggested by the authors assumes the creation of a system of compensation payments as the main source of financing of land rehabilitation and soil conservation measures. An original system of calculation of such payments has been tested for radioactively contaminated lands in Plavsk district of Tula oblast. It is argued that compensation payments for radioactively contaminated agrocenoses should be higher than those for natural cenoses.



Alternative technologies for remediation of technogenic barrens in the Kola Subarctic
Abstract
The efficiency of remediation of technogenic barrens under the reduction of air pollutant emissions from the Severonikel smelter in the Kola Subarctic is determined largely by the soil state and the technology applied. The covering of the contaminated soils with artificially made material based on organomineral substrates and the following liming and fertilization promoted a sharp and long-term reduction of acidity, decrease in the biological availability of heavy metals, increase in the supply with nutrients, and improvement of the life state of willow and birch plantations. The effect of economically more profitable chemo–phytostabilization is short-term; it requires constant maintenance. Under the current production and a high level of soil contamination, repeated measures are required to optimize the soil reaction, supply with nutrients, and to correct the availability of heavy metals in the soils based on the results of continuous monitoring



Changes of the content of oil products in the oil-polluted peat soil of a high-moor bog in a field experiment with application of lime and fertilizers
Abstract
A field model experiment on stimulating the activity of native oil microorganisms–decomposers was performed on an oil-polluted area in a high-moor bog under its total flooding in the northern taiga (Western Siberia). For two summer months, the doses of lime and nitrogen, phosphorus, and potassium fertilizers applied have caused a decrease in the oil products (OP) content by 54% relative to their initial amount. The decrease of the OP content in the soil profiles was nonuniform, and at the depth of 30–50 cm it was accompanied by the acidification of peat. The stimulation of the activity of aboriginal microorganisms by applying lime and mineral fertilizers led to the development of migration processes with the participation of oil and products of its transformation. These processes differed from those in the soil without application of lime and fertilizers. An original technology of applying lime and fertilizers providing minimal disturbances the upper 50-cm peat layer is suggested.



Accumulation of polycyclic aromatic hydrocarbons in soils and plants of the tundra zone under the impact of coal-mining industry
Abstract
Thirteen polycyclic aromatic hydrocarbon (PAH) compounds were identified in organic horizons of tundra surface-gleyed soils ( Histic Stagnosols (Gelistagnic) and plants. The total content of PAHs in contaminated soils exceeded the background values by three times. Concentrations of low-molecular weight hydrocarbons in soils at different distances from the coalmines were relatively stable. Concentrations of highmolecular weight hydrocarbons had a distinct maximum at a distance of about 0.5 km from the source of emission. The increased values of correlation coefficients were found between PAH concentrations in organic soil horizons, plants, and coal of the Vorkutinskaya mine. Mostly low-molecular weight structures predominated in the organic soil horizons and in the studied plant species. The maximum capacity for the biological accumulation of PAHs was displayed by Pleurozium schreberi and the minimum capacity was displayed by Vaccinium myrtillus. Mosses and lichens actively absorbed polyarenes from the surface; most of the PAHs were transported into the plants. This phenomenon was not observed for Vaccinium myrtillus Concentrations of PAHs on the surface and in plant tissues decreased with an increase in the distance from the mine. Distribution of polyarenes in plant organs was nonuniform. Insignificant excess of concentration of polyarenes was found in dead part of Pleurozium schreberi in comparison with its living part. The accumulation of polyarenes in the leaves of Vaccinium myrtillus was higher than that in its stems and roots.


