The opportunities of the laser diffraction method in the assessment of the microstructure condition of the soil are shown on the samples of humus layers of the following soils (agro soddy-podzolic (Eutric Albic Retisol (Loamic, Aric, Cutanic, Ochric)), Moscow oblast; gray (Luvic Greyzemic Phaeozem), Tulskie zaseky; migration micellar chernozem (Haplic Chernozem (Loamic, Pachic)), Kursk oblast; ferralitic (Rhodic Ferralsol), Norfolk island). The ways of samples preparation to the analysis are considered: boiling, stirring (80 min-1) of the attenuated water suspensions, intense stirring (2500 min-1) of the water suspensions, mixing of the suspension by the glass stick. The assessment of the preliminary saturation of samples by the distillated water before the samples preparation is given. The assessment of possibility of the implementation of soil micro structure indices, developed on the basis of sedimentation methods was made. The impossibility of the implementation of Kachinskiy dispersion coefficient to the results obtained by the method of laser diffraction was shown. The intense stirring (2500 min-1) of the water suspensions during the 10 minutes is recommended as the standard method of the soil samples preparation for the further microagregate analysis by the method of laser difraction. Such a way of soil samples preparation doesn’t lead to the modification of the properties of the solid body and provides the stability of the results. The results of the microagregate analysis by the method of laser diffraction, presented by the even distribution of particles by the size are characterized by the high informativity. The correlation of different ways of soil samples preparation along with the high accuracy of the method allow us to reveal the specificities of microstructure soil organization.

The rheological properties of two profile`s horizons of soddy-podzolic and agro soddy-podzolic soil were studied by the amplitude sweep test on a rheometer MCR-302 (Anton Paar, Austria) on samples of natural structure (pastes) and disturbed structure (monoliths). Curves of the elasticity and viscosity modules determine the linear viscoelasticity range (LVE-range) of soil pastes and monoliths, the elastic modulus in linear viscoelasticity range as a characteristic of strength of structural bonds, the transition from viscoelastic to viscous behavior-the intersection of the elasticity and viscosity modules. It is established that the LVE-range of monolithic samples is more than paste samples, they are characterized by stronger structural bonds in the linear viscoelastic range; however, the destruction of structure in monolithic samples occurs at lower deformation values than in paste samples. The differentiation of the rheological parameter values of the upper part of profile of soddy-podzolic soil is caused by the large content of organic matter in the humus horizon and the facilitation of the soil texture in the eluvial horizon. The strength of structural bonds of the samples of the lower horizons of soddy-podzolic and agro soddy-podzolic soils differ insignificantly.

The assessment of the microbial biomass structure in the soil samples from A and C horizons, stored at the temperature of +5 and -70°С was conducted by a luminescence method. For the samples from the humus layer a significant decrease of biomass during the cryostorage was revealed. However, in the sample from the mineral layer at the same storage conditions such a decrease occurred in a lesser degree. The decrease of fungi mycelium length was observed in the sample, which was stored at the temperature -70°С. Also, the decrease of the number of fungi spores with large diameter ( d > 5 mkm) and the absence of the largest spores ( d > 7 mkm) was observed. The mycelium length of the pure culture of Cadophora novi-eboraci fungi was a bit decreased after the storage of samples at +5°С. Under conditions of negative temperatures (-18 and -80ºС) the mycelium length was decreased by 28% during the first days, and by 32% on the 14-th day of the incubation. The data obtained stipulate that the storage of samples under conditions of negative temperatures leads to the decrease of biomass and number of microorganisms within the soil. Therefore, it is not recommended to store soil samples under conditions of negative temperatures if it is planned to assess the structure of microbial biomass by the direct method of luminescent microscopy.

The influx of rare-earth elements into the soil is associated with ecological risks. The absence of regulatory standards for these elements in the environment makes it necessary to assess their impact on the biota. The use of biotests may be helpful not only in revealing potential integral toxicity according to the changes in growth indices, but also in characterizing the impact of the studied agent on the genetic apparatus of test object cells. In this study we used the test system with bulb onion ( Allium cepa L.) to сharacterize integral phytotoxicity, and also cyto- and genotoxicity of lanthanum and cerium chlorides. The following lanthanum concentrations were tested: 0 (control), 2, 5, 10, 30 and 50 mg/l. A significant decrease in the proportion of dividing cells (mitotic index) for all of the investigated concentrations of lanthanum was shown, and cerium was found to decrease mitotic index at concentrations 5 mg/l and higher. The frequency of mitosis pathologies was significantly higher compared to the control group for lanthanum and cerium at concentration 50 mg/l, which suggests possible genotoxicity of these rare earth elements. The decrease in mitotic index was accompanied by inhibited onion root elongation in biotests with both lanthanum and cerium.

The experience of space images use for creation of land use map for the terriotory of the Svetloyar irrigation system and neighboring households is considered. The investigation territory is located in the north-west area on the right bank part of Kaspian lowland (Volgograd oblast). The land use map reflects the actual conditions of the object and contains the information about the fields under different crops and mixed-age laylands. In order to determine the mixed age layland, the field data were used, which allowed us to reveal the vegetation composition, which varies due to the age of layland. Space images also reflect this specificity. The creation of land use map is a necessary stage of soil-saline map creation. The complex analysis of data obtained on the basis of space images, recognaissance operations and field works, meliorative cadasters, land use map allowed us to assess the actual conditions in the investigation region. We also revealed the following: at the present slightly more than 50% of irrigated lands are used, 86% of them are occupied by winter wheat, and the rest of the area is under the forage grasses. The other half of lands is presented by mixed age laylands. During the crop cultivation preirrigation and drop irrigation was used. As a result the ground water level decreased below the 5 m almost everywhere.

Classification of surface bodies on technogenic parent materials is rather disputable. On one hand, the technogenic surface bodies (TSB) are predecessors of soils, on the other hand - they are made by humans, hence, differ of the natural soils by their origin. In the Russian soil classification system (versions of 2004 and 2008), the TSBs are subdivided by the kinds of human activities responsible for their formation. Moreover, the taxonomy of TSBs is a separate system beyond the soil classification, and the names of its objects are artificial and deliberately cumbersome in order to emphasize their “non-soil” essence. This system was invented by Valentin Tonkonogov, and it comprises two hierarchical levels, namely, groups and subgroups. In accordance with this system, an attempt was made to classify TSBs on coal dumps and iron ore mine tailings located in two landscape zones: forest-steppe and aspen-fir taiga in Kemerovo oblast. A third taxonomic level - “triba” - is proposed, with chemical and morphological properties of technogenic materials as differentiating criteria.

The issues of improving land relations, rational land use and adaptation to climate are considered as the basic directions of the development strategy of the agro-industrial complex, discussed and supported by the Presidium of the RAS (18.04.2017). It is emphasized that the main determinant of a successful solution of all problems in modern land use management in Russia are measures to protect the soil cover, an adequate assessment of its condition and a fundamental change in land relations that the Federal Land Service should resolve. The consequences of the inconsistent implementation of land reform in the post-Soviet period, the main negative outcome of which are the latifundism of large agroholdings and companies, are shown. The resource potential of the modern land fund of the country is estimated to be one third less than the pre-perestroika one. The main direction in the development of agroproduction is modernization, intensification, development of land reclamation and chemicalization, which will allow us to reach, at a minimum, the average world yield level (3.5 tons / ha). The risks associated with the proposed land expansion (plowing) of land withdrawn from circulation, including marginal and badlands, are discussed. Examples of micromorphological indication of soil degradation and uncertainty associated with the detection of the results of modern space images analysis are shown. The necessity of actualization of information on soil degradation and assessment of suitability (favorability) for active agricultural production is substantiated.