Bulletin of Nizhnevartovsk State University

Bacterial fertilizers are an effective technology for growing crops under saline conditions. The effect of biofertilizer (BF) based on biochar and halotolerant strain of growth-promoting rhizobacteria Pseudomonas sp. STF14 on the growth and some physiological and biochemical characteristics of salad mustard (Brassica juncea (L.) Czern, variety “Chastushka”) under salt stress caused by sodium chloride was assessed. Mustard plants were grown in pot-scale experiment for 21 days under natural conditions. The experiment included 4 treatments: control peat soil (PS); PS + BF (2.5%, v/v); PS + NaCl (80 mM); PS + BF (2.5%, v/v) + NaCl (80 mM). From the 7th day after planting the plants were watered with a salt solution twice a week. Adding BF increased the length and fresh biomass of mustard shoots compared to the control (by 23% on average), while NaCl treatment inhibited their growth. BF added separately or together with salt increased photosynthetic pigments. Separate application of BF and NaCl led to the malondialdehyde in mustard leaves increasing by 1.4 and 1.9 times, respectively compared to the control. However, when combined, malondialdehyde decreased by 1.6 times. Watering mustard plants with a saline solution increased the content of free proline by almost 5 times and Na⁺ by almost 7 times, while BF + NaCl significantly reduced their amount. Thus, the use of BF under salt stress conditions contributed to the improvement of mustard growth and increased its resistance to sodium chloride.

The object of the study was water samples, cultures of green microalgae Parachlorella kessleri U1 and Chlorella vulgaris I2, Maybalyk Lake (Astana). The aim and objectives of the study were to study the bioremediation potential of a consortium of two strains of microalgae Parachlorella kessleri U1 + Chlorella vulgaris I2 (hereinafter U1+I2) through the algolization of Lake Maibalyk according to microbiological and hydrochemical indicators. This lake is a large lake in Astana with fishery importance. The state of the reservoir is reflected in the state of the capital's air basin. A study of the water quality of Lake Maibalyk was conducted on the main morphometric, hydrochemical and hydrobiological indicators in May and June of 2020. To study the effect and determine the efficiency of using microalgae, preliminary biomass production and algolization of the U1 + I2 consortium were carried out. The introduction of a consortium of microalgae showed an improvement in the sanitary and microbiological indicators of the reservoir after just one month, due to its high antimicrobial properties and a decrease in such groups of bacteria as ammonifiers, coliforms, heterotrophic bacteria, coli group bacteria, pseudomonas, wax bacilli, staphylococcus, enterococci, enterobacteria, salmonella, fungi and yeast. After algolization for 30 days by the consortium I2+U1, an improvement was recorded not only in the organoleptic characteristics of water, but also in a number of hydrochemical parameters, including a decrease in COD, suspended solids, iron, SSAA and phosphates. . An increase in transparency, a decrease in water color and the absence of a specific odor were also noted. It was found that, although the content of BOD₅, nitrates, sulfates in the original sample did not exceed the MРC values, the introduction of microalgae had a positive effect on reducing the concentration of these substances, which significantly affected the quality of the water in the reservoir. The results obtained can serve as a basis for developing environmentally friendly biotechnologies to improve water quality. In the future, it is necessary to conduct studies in triplicate, which will increase the reliability and quality of the data obtained, which will allow more effective assessment of the state of the ecosystem of the reservoir and ensure the safety of water use.

The article presents a new assessment of the small mammal communities in the sub-taiga of the Iset-Pyshma interfluve (the Kurgan Oblast). It shows that the species composition, groups of common and dominant species, and indicators of the total abundance of insectivores and rodents are largely determined by the specificities of the animal recording method. The use of ditches with pitfalls or polyethylene guide fences is more effective than the use of trap-lines. A total of 19 small mammal species were recorded, including 18 that were captured using ditches with pitfalls or polyethylene fences, and 14 that were recorded using trap-lines. The common species group in the subtaiga included the common shrew, Laxmann's shrew, root vole, common vole, and field vole, while the dominant species were the common shrew, Laxmann's shrew, root vole, and common vole (recorded using ditches with pitfalls and polyethylene guides). In trap-line records, no common species were identified. In this case, common and abundant species were absent, and the dominant species were the common shrew and the herb wood mouse. The pattern of small mammal species ratios in the study areas in 2021 and 2024 was influenced by the different proportions of forested and open areas. Regardless of weather conditions in spring and summer of a particular year, small mammals were most densely concentrated in near-water and forested biotopes. Total abundance was lower in pine forests and open spaces. The faunistic composition of the small mammal population in the subtaiga of the South Trans-Ural region is European-Transpalaearctic, both in terms of species diversity and individual numbers. The proportion of Siberian and tundra-forest-steppe species is much smaller.

The aim of the study is to determine the main patterns of physical development (PD) of students of a northern university. The objectives included collecting data on somatic and physiometric parameters of first-year students of Nizhnevartovsk State University (young men and young women aged 17–18 years), retrospective analysis of the indicators obtained during annual examinations since 2003 (cumulative total: 1285 young women and 1065 young men). The study used standard methods for assessing the level of physical development and functional capabilities of the body. Statistical data processing was carried out using the Microsoft Excel, Statistica 10.0 software package. As a result of the analysis, the following features of PD were revealed: from 2003 to 2024, young men and young women showed an increase in somatometric indicators, such as body length and weight, which corresponds to the secular trend of increasing these parameters. Along with this, a decrease in muscle strength of the leading hand is noted in both young men and young women. A linear trend of decreasing vital capacity of the lungs is observed, correlating with the chest circumference indicators, which signals a negative trend in the decline in the functional capabilities of the respiratory system of the younger generation. A significant deterioration in strength capabilities among students in 2020 may be a consequence of a decrease in the level of physical activity during the COVID-19 pandemic. The results of the study emphasize the importance of continuous monitoring of the physical development of students and the use of comprehensive measures to maintain health and increase the physical activity of student youth.

The regional geochemical characteristics of the soil cover of the “Siberian Uvaly” natural park’s territory have been revealed. The comparative analysis of the background soils properties in Siberian Uvals (Podzol Arenic Turbic, Histosols Gelic and Fluvisols) and technogenic surface formations (TSF) constructed at oil and gas production fields was conducted. The chemical properties of the main types of soils were studied using traditional analytical methods of environmental monitoring: reaction of the medium, content of organic matter, mobile phosphorus compounds, content of the main salinizing sulfates and chloride ions in the water extract. Concentrations of mobile forms of some heavy metals (Pb, Ni, Cr, Cu and Mn) and the content of petroleum products in the main types of soils of the study area were also determined. Regional peculiarities of the geochemical background of the natural park were identified: increased content of oil products, manganese and zinc in organogenic horizons of natural background soils, located within the territory of specially protected natural areas, which act as a kind of reserve for maintaining the natural environment in its natural state. The presence of saline substances in the area may be a consequence of sea salt being transported by southern winds and with deposited on the uplands of the Siberian Uvaly. It could also be due permafrost processes in the process, which release salt from marine sediments. Oil and gas companies can use the research results to compare the initial contamination of licensed areas with background indicators when planning field development. Intensive oil and gas development of territories, accompanied by the impact on geosystems, requires systematic monitoring of the environment.

This article presents an analytical review of scientific studies focusing on the issue of microplastic pollution in freshwater bodies in Russia. The study examines in detail the primary sources of microplastic particles entering aquatic environments, including domestic and industrial wastewater, rainwater runoff, urban dust, and diffuse sources such as the decomposition of plastic waste in landfills and natural environments. Special attention is given to the methods of collecting water and sediment samples employed by various research groups. Contemporary approaches to microplastic detection and identification are described, including visual methods using optical and electron microscopy, Fourier-transform infrared (FTIR) spectroscopy, and Raman spectroscopy. The review presents data on the impact of microplastics on biological organisms and ecosystems, including disruptions in trophic networks and impairments in the functioning of the endocrine, reproductive, and immune systems. Aspects of the mechanical and toxicological effects of microplastics are considered, as well as the processes of contaminant sorption onto their surfaces. The conclusion highlights the need for further standardization of research methodologies and additional investigations to gain a deeper understanding of the extent of microplastic distribution in freshwater ecosystems, particularly in regions with insufficient empirical data. The importance of developing comprehensive strategies to minimize microplastic pollution in freshwaters is emphasized.