Home – Home – Jornals – Contemporary Problems of Ecology 2004 number 3

A diverse natural variety of the bulk content of microelements due to differences in the genesis of sediments and the leading role of fine particles in them is discovered in the soils of West Siberia. Several natural soil-geochemical provinces and industrially polluted territories have been revealed, in which there is or can be imbalance of chemical elements in alimentary chains. A promising character of the use of relations between the bulk content of separate microelements for investigating the genesis of soil-forming rocks and soils is demonstrated.

The effect of genesis, grain size distribution, mineral composition, physicochemical and chemical properties of soil-forming rocks, climate, relief, and soil formation on the bulk content of microelements, regularities of their spatial and profile distribution in the solids of West Siberia is considered. The revealed regularities correspond to the general laws governing the formation of lithologic and lithochemical composition of sediments, and associations of chemical elements in them. A connection of microelements in the surface sediments of the South-East of the West Siberian Plane with the Altai-Sayan fold region is confirmed. It is noted that aeolian sedimentation and exogenous processes in Holocene could level the granulometric and microelement composition of the upper layer of soils, reduce their genetic differences and connection with soil-forming rocks.

The paper deals with the investigation of pool of viable microorganisms in habitats with an increased content of potentially toxic elements. The role of soils as a source of secondary contamination is demonstrated for the contacting media: the surface layer of the atmosphere, small water currents, phytocenoses with toxic microorganisms. The results of the recovery of urban environment involving microbial and plant agents are shown.

The features of soil salination are investigated depending on the relief, depth at which underground water occurs, lithologic structure, and composition of rocks. The resources of calcium carbonate in the illuvial carbonate horizon of the southern black soil are higher than its initial lithogenic content in the soil-forming rock by 20-25 kg/m². A negative balance of carbonates (20-60 kg/m²) is observed only in highly leached soil of close-mouthed micro-depressions. The zones of accumulation of carbonates and gypsum in the profile are strictly localized, they are always adjacent to each other, never overlap and never get disconnected. Eluvial-illuvial character of salt distribution over the profile in agreement with their solubility is an evidence of the leading role of atmospheric salts in the formation of the salt profile of autonomous salts.

Natural conditions of soil formation in the Ishym steppe are characterized and the main genetic characteristics of the southern black soil are described. A probable way is outlined for the development of soils of placore regions in watersheds in the South of the Ishym plain in view of changes in soil formation conditions during the Sartan cool age and in Holocene. The climatic factor is assumed to be governing for the evolution of placore soils.

The results of natural and land-improvement status of the soils of West Siberia allowed distinguishing the integral criteria of estimations of the land-improvement status of black soils: water permeability of the soil-earth (ameliorating) layer and sodostability of the plough-layer. The introduction of these criteria, as supplements to the generally accepted ones, into the methodology of land-improvement soil science allows one to reveal the ecological land-improvement potential of the black soil and to some extent predict their response to irrigation.

Two sources of mineral nutrition elements of swampy phythocenosis are considered: natural water arriving at a swamp, and soil subjected to swamping. The soil under swamping is determined as a leading source.

The problem of diagnostics and evaluation of the soil-forming potential of the industry-caused landscapes is discussed for the Kuznetsk Coal Basin as an example. Specific features of the top-soil composition and evolution of soils in these landscapes are analysed, their connection with the industry-related and natural factors, as well as with the conditions of soil formation, is determined. The soil-geographic, soil-genetic and mapping methods are proposed for the diagnostics and evaluation of the soil-ecological status of industry-caused landscapes.

The features of the accumulation of organic components at the initial, turf, and humus-accumulating stages of soil formation in technology-caused landscapes are investigated. Imbalance of the leading soil-forming processes (synthesis, accumulation and humification of the organic matter) is demonstrated. The factors having a negative effect on the intensity of their development are considered.

The spatial and functional-genetic features of the main soil combinations in the Baraba plain within the limits of its forest-steppe region are investigated. A morphogenetic characterization of formations comprising the structure of the top-soil is presented, along with the morphometric characterization of its component composition. Mechanisms of top-soil differentiation and the character of mass transfer from one its component to another are determined.

The paper deals with the problems of anthropogenic desertification in the southern regions of the Novosibirsk District. The joint effect of climatic factors (an increase in aridity) along with anthropogenic ones (ploughing up, pasture digression, etc.) is described, these factors being the reasons of ecological crisis of arid areas. Anthropogenic load on ecosystems caused activation of deflation processes both in ploughed soil and in natural forage acreages, expansion of the area of soil salinity, and a decrease in the biological variety of growth.

The environmental role of sulphur-containing compounds originated from industrial activities is considered. The priority sulphur-containing atmospheric pollutant is sulphurous anhydride (sulphur dioxide) which is emitted by many industrial facilities. When present in the air in concentrations above the maximum permissible level, this compound is hazardous for living organisms and can cause their death. Expansion of sulphur dioxide in the atmosphere is of local character. The major part of this compound is deposited on the underlying surface near the sources (at a distance of 0,5-5 km) together with gaseous and solid emissions. Only aerosol compounds are included into long-range transport thus forming the background concentrations in the atmosphere. For sulphur dioxide, the soil serves as a geochemical barrier in which this compound is substantially or fully mitigated, depending on the buffer properties of the soil, as well as on the properties of the corresponding products in emissions. The sink of man-caused sulphur dioxide in the regions where the natural sulphur content of the soil is low causes enrichment of the soil compensating for the deficiency of this nutritive element in plants.

The parameters of soil fertility are reported for the application of fertilizers and cultivation under different soil and climatic conditions. The influence of the leading anthropogenic factors on the changes in the parameters of nitrogen conditions in soil, on the assimilation of nitrogen in plants and on the productivity of plants is demonstrated. A schematic of the main fluxes of nitrogen is presented and the ways to adjustment of nitrogen nutrition in agricultural ecosystems are outlined.

An estimation of the potassium status of zonal soils of West Siberia is presented, the content of total potassium and its forms in the main types of soils is shown. The parameters of the soil potassium diagnostics are reported. The changes in the potassium status of soils in agricultural ecosystems are investigated. The features of transformations of potassium forms in soils are considered.

On the basis of the fractional composition data, the changes in the reserves of mineral phosphates are shown and the transformation of superphosphate and phosphorite powder in the soils of different extent of washing is considered. It is revealed that erosion processes result in a decrease in phosphate-mobilizing activity and in the content of phosphorus-containing compounds most available for plants, while the phosphate capacity of the soil increases.

A comparative estimation of the long-fallow and old-arable grey forest soil with respect to granulometric composition, total content of organic matter and humic acids, total and nitrate nitrogen, mobile phosphorus and potassium compounds is presented. Changes in arable soil with respect to a 40-year  fallow land are the evidence of its degradation as a result of agricultural tenure of many years.

The transect in the mountain forest-steppe of Tuva including petrophyte steppe, meadow vegetation and forest illustrates a gradual transformation of the grass litter into the forest one. Smooth changes in the properties of plant residues and the formation of stratified profile of the litter occur in the sequence of phytocenoses from petrophyte steppe to larch forest. On the basis of the established features of the structural arrangement and stratification of the profile of litter, we assume that the grass subjacent layer, similarly to the forest subjacent layer, is the organogenic soil horizon.

Some heuristic possibilities of the symmetry analysis with respect to the investigation of the system properties of soils are considered. In particular, interconnections between thermodynamic characteristics of the soil moisture and structural parameters of the solid phase of soil samples are analyzed. It is demonstrated that the notions of soil moisture and potential admit the possibility of generalization in the investigation of the combined action of different factors.

The results of calculations of the properties of various soils of the South of West Siberia over their probabilistic statistical distributions are presented. It is demonstrated that the statistical entropy of the properties can serve as one of the systemic criteria of the evolution and dynamics of top soil under natural and anthropogenic processes. It is established that the entropy of humus content of soil within one zone depends on the grain size distribution. It is proved that deflation, ploughing and irrigation decrease the entropy of humus content, while soil-protecting agriculture increases it.

It was shown that the reclamation of industrial barren, resulting from the long-term heavy metal pollution of a zonal forest ecosystem by aerial wastes of Monchegorsk mining factory, led to the substantial increase in metabolic activity and shifts in the physiological profile of the bacterial community in the upper soil horizon, despite very high concentrations of nickel and copper. These changes were due to the input of readily available organic substrates with litter and rhizodeposition of the grass plant used to revegetate the barren site. However, the size of the bacterial community (numbers and biomass) was most likely negatively affected by the high soil concentrations of heavy metals. Thus the recovered metabolic diversity of the bacterial community under revegetation with azonal grass species, capable to sustain plant cover and primary production for several years on soil with very high heavy metals concentrations, is very important for the recovery of soil processes in particular and ecosystem as a whole.