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The article provides materials on the natural restoration of land cover in the territory occupied by the waste storage facility of the pulp and paper industry. The article contains information on the level of soil fertility formed on this territory as a result of decomposition of organic waste over 25 years. The composition of the phytocenosis is presented. The article provides materials on the ecological state of the studied object, and also considers the technological operations of reclamation of an authorized landfill in the areas of forestry and recreational land use, taking into account the ecosystem formed at the storage facility.

Purpose. To study magnesium status of patients having paroxysmal atrial fibrillation (AF) based on the use of an integrated clinical and laboratory approach. Methods. A prospective cohort study included 58 patients of the cardiology department of New Hospital Medical Association. The main group consisted of 32 patients having frequently recurring paroxysmal AF, the control group consisted of 26 patients without paroxysmal rhythm disturbance. The clinical status, Holter ECG monitoring data, the test results for magnesium deficiency (MD) clinical evidence, laboratory evidence of calcium, magnesium in blood plasma and formed elements, magnesium in whole blood, free fatty acids (FFA) and osmolality in blood plasma were assessed. Results. The score obtained when assessing MD clinical evidence was significantly higher in the main group patients compared with the control group (16.5 (11÷21) vs. 13 (8÷15), p

A description of five mathematical models of the water-retention capacity of soil is given, taking into account the hysteresis phenomena. A computational experiment was carried out with these models using data on sandy soil. The experiment consisted of: (i) tuning of the models (parameter identification) by the method of dot-approximation of experimental data on the main drying and wetting branches of the hysteresis loop using an optimizing algorithm; (ii) the predictive calculation of the scanning branches of the hysteresis loop; (iii) a comparison of the errors in tuning results and the predictive calculation using the Williams-Kloot criteria. The commensurate and sufficiently low errors in the adjustment of the models have been achieved. The differences in the calculation of the scanning hysteresis branches are revealed. The practical significance of the mathematical models presented is to ensure the calculation of precision irrigation rates. The application of such rates in irrigation farming will help to prevent excess moisture from flowing beyond the root layer of the soil under the influence of gravity and, thus, to minimize the losses (unproductive consumption) of irrigation water, fertilizers, meliorants and plant protection products, and also reduce the risk of groundwater contamination with agrochemicals and eutrophication of water bodies.

This paper is dedicated to the Gulf of Cheboksary. The gulf has an important recreational and decorative function. It has been an integral part of the urban landscape for several decades. There is an eutrophication process, accompanied by the development of blue-green algae and the appearance of an odour in early spring, despite the water quality improvement measures. Measures that will improve the water exchange in the Gulf are proposed in this paper. Problems with the sanitary condition of the water body can occur without taking these measures. Therefore, the theme of this research is quite urgent.