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An attempt has been made to analyze the possibility to use nonequilibrium thermodynamics for the soil dynamic open systems’ treatment. Entropy change of such a system is expressed by the entropy sum produced within the system and the entropy coming from or going into the outer sphere.

In the steady state, dynamic soil‐formation processes occur within an organized structure and are characterized by stable parameters close to equilibrium. Accordingly, when examining soil, one can proceed from the conventional thermodynamic equilibrium. However, the matter of Onzager‐Prigozhin general phenomenological theory applicability to soil processes is more complicated. To study soil stability it is necessary to go beyond the limits of linear thermodynamics.  相似文献   
2.
Temporal changes of eroded soils in the southern Cis-Ural region (Republic of Bashkortostan) depending on their agricultural use during the period from 1975 to 2011 were studied. In the northern foreststeppe zone, the development of erosion processes was retarded upon the use of soil-saving management practices and grain-fallow-grass crop rotations. In slightly eroded light gray forest soils (Eutric Retisols (Cutanic)), the thickness of humus-accumulative horizons and the content of humus increased; the conversion of cropland into permanent fallow was found to be the most efficient measure to control soil erosion. In podzolized chernozems (Luvic Greyzemic Chernic Phaeozems) and typical chernozems (Haplic Chernozems) of the Cis-Ural steppe, the content of humus in the plow layer under grain-row crop rotation and classical soil management decreased, especially in moderately eroded soils. The development of water and wind erosion on slopes depended on the slope shape: the texture of soils at different degrees of erosion on slopes with free runoff became coarser by one gradation after 35 years; in the presence of linear obstacles in the lower part of slopes, the content of fine fractions in moderately and strongly eroded soils increased.  相似文献   
3.
Specific features of the horizontal and vertical distribution of uranium and thorium in soils and parent materials of the Southern Urals within the Bashkortostan Republic have been studied with the use of mass spectrometry with inductively coupled plasma. The dependence of distribution patterns of these elements on the local environmental conditions is shown. A scale for soil evaluation according to the concentrations of uranium and thorium (mg/kg) is suggested: the low level, up to 3; medium, up to 9; high, up to 15; and very high, above 15 mg/kg. On the basis of to this scale, the ecological state of the soils is evaluated, and the schematic geochemical map of the region is compiled. The territory of Bashkortostan is subdivided into two parts according to the contents of radioactive elements in soils: the western part with distinct accumulation of uranium and the eastern part with predominant thorium accumulation. This finding supports the charriage (thrust fault) nature of the fault zone of the Southern Urals. The vertical distribution patterns of uranium and thorium in soils of the region are of the same character. The dependence between the contents of these two elements and rare-earth elements has been established. The results of this study are applied for assessing the ecological state of soils in the region.  相似文献   
4.
Eurasian Soil Science - The results of the study of the properties of urban soils of the city of Sibay located in the mining region of the Republic of Bashkortostan are presented. A specific...  相似文献   
5.
A model is given for optimizing the structure of agricultural production at farmers’ farms in the Republic of Bashkortostan. The size of farmers’ farms making it possible to obtain maximum profit from producing plant and animal products are proposed for six zones of the republic.  相似文献   
6.
The soil cover of Tra-Tau and Yurak-Tau shikhans (monadnocks) has been examined. Leached and typical medium-deep chernozems are developed on colluvial fans on the footslopes and on the lower parts of slopes, whereas typical calcareous thin slightly and moderately gravelly chernozems are developed on the upper and medium parts of slopes. The leached and typical chernozems of the footslopes correspond to zonal soils of the adjacent plain areas, though they have some specific features related to the local topographic conditions. These soils are somewhat thinner than plain chernozems and are characterized by the perfect granular water-stable structure, the high content of humus of the humate type, the high content of exchangeable cations, strong acid-base buffering, and high enzymatic activity. These features predetermine their high tolerance towards technogenic impacts. The concentrations of highly hazardous substances of the first toxicity class (mercury, arsenic, lead, and cadmium) and of moderately hazardous substances of the second toxicity class (copper, zinc, and nickel), as well as the concentrations of low-hazardous elements (manganese and iron) in these soils do not exceed provisional maximum permissible concentrations of these substances in soils irrespectively of the slope aspect. No changes in the physicochemical and biological properties of the soils under the impact of technogenic loads from Sterlitamak industrial center have been identified.  相似文献   
7.
Eurasian Soil Science - The influence of ground fires of different ages on the morphological, hydrophysical, and physicochemical properties and on the humus status of dark gray soils (Luvic Retic...  相似文献   
8.
The contents and distribution patterns of alkali and alkaline earth metals in soils and rocks of the southern Cis-Ural region were studied. A database on the contents of these metals was developed, the soils were classified with respect to their provision with these metals, and corresponding schematic maps showing their distribution in soils of the region were compiled. It was found that the contents of these metals decrease from east to west (from the Yuryuzan–Aisk Piedmont Plain to the Ufa Plateau and to the Belebeevsk Upland), and their distribution patterns change. Among alkali metals, the highest accumulation in the soils is typical of potassium, sodium, and cesium; among alkaline earth metals, of strontium and barium.  相似文献   
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