The purpose of the study is to reveal the mechanisms of interaction of some acid ameliorants in the process of chemical reclamation of Sodic Solonetzes-Solonchaks (SSS). The experiments have been carried out within 2018-2020 under laboratory conditions using soil column techniques. 13 soil samples have been collected from Ararat valley, Republic of Armenia. These soils have a high alkaline reaction (pH 9.5-10.5), a sodium exchangeable percentage (ESP 44.5-74.0%) and electrical conductivity (EC 12.4-42.2 dS cm-1). It has been shown, that in the case of iron sulphate application the products of its hydrolysis promote soil dealkalization and improvement of soil physical properties due to creation of iron-clay complexes accumulated in the soil primarily in crystalline form (66-67 %). It has been revealed, that the penetration depth of 1% of sulphuric acid and iron sulphate solutions during the chemical reclamation is 8-12 cm, and the accumulation of gypsum in topsoil (0-12 cm) is observed. Due to the higher solubility of magnesium sulphate in the process of acidification, soil dealkalization and the increase of filtration rate of soil solutions (10-12 cm day-1) are watched. During the soil leaching process, the newly-formed gypsum plays a major role in further dealkalization process of soils and regulation of exchangeable Ca and Mg relation in optimal range. It is shown, that in the process of acidification, the pressure of the formed carbon dioxide gas (CDG) in the soil may reach up to 2.2 atm, in which the solubility of calcium and magnesium carbonate are increased, and the share of CDG in soil dealkalization process is in average 50%. The results obtained allow for the opportunity to recommend improvements of SSS chemical reclamation technology.

Every year the world's population moves more and more to cities. Today 56% of all people live in cities, the forecast for 2050 suggests an increase in this figure to 60%. Sustainability for urban development is critical, as it addresses such issues as water and air pollution, waste management and resource consumption. Green cities use environmentally friendly practices to promote the health of the urban environment and, as a result, improve the quality of life. Nature-based solutions represent an interdisciplinary issue, including the competencies of urban planners, landscape designers, engineers, hydrologists, ecologists, economists, etc. and are critically needed for climate change adaptation. The paper is focused on the role of blue-green infrastructure as key adaptation strategy for climate change. Innovative approaches and technologies as examples of the best urban management strategies promoting a more sustainable urban environment resistant to climate change will be presented and discussed.

This study aims to address the critical issue of water scarcity, which is being intensified by climate change and presents significant challenges to rain-fed agriculture, especially in arid regions. The research focuses on enhancing winter wheat grain yield productivity under rain-fed conditions through the utilization of locally produced, environmentally friendly hydrogel polymers. The methodology involved a field experiment conducted in the Spitak community, Armenia, from 2022 to 2023, covering an area of 630 m². Along with control groups, the study had 21 experimental treatments that used Aquasource and Van polymers in different ways, with and without nitrogen, phosphorus, and potassium (NPK) fertilizer. The findings indicated that the application of Aquasource and Van polymers at doses of 50-100 kg ha⁻¹ and 750-1000 kg ha⁻¹, respectively, without fertilizers significantly increased soil moisture absorption during the tillering and heading stages by 11.5-12.5% and 5.5-7.5%, compared to the controls. On the other hand, using these polymers with NPK fertilizer (N50P50K50 and N100P100K100) together made it harder for plants to absorb water, especially when more polymers were used. Soil moisture levels had a substantial impact on winter wheat grain yield metrics during these growth stages, demonstrating a strong correlation (R = 0.71-0.91). Enhanced moisture absorption resulting from polymer application led to a 22-24% increase in winter wheat grain yield. The practical implications of this study lie in its identification of key factors that influence winter wheat yield in rain-fed agriculture, particularly regarding locally sourced polymer dosage and application methods, both independently and in conjunction with fertilizers.

The purpose of the study is to cost-effective and environmentally friendly procedures for the condensation of waste generated from brandy production (distillery dreg) for agricultural use. The experiments were carried out between 2020–2022 under laboratory conditions. It has been shown that in order to reduce the significant cost of distillery dreg transportation, it is advisable to carry out its condensation by means of distillation. Laboratory studies and feasibility calculations revealed that distillery dreg may be condensed by up to five times, allowing for a corresponding reduction in transportation costs, while maintaining its quality indicators. It is suggested that the brandy alcohol distillation process be altered in a way that will allow for the production of condensed distillery dreg substance, with minimal additional energy expenditure and capital investment. The suggested method makes it possible to not only improve the ameliorative conditions of agricultural land, but also to address significant environmental protection issues.

Background: Enhancing productivity in rain-fed soils is crucial for sustainable agriculture. This study evaluates the potential of two newly synthesized water-absorbing polymers, Aquasource and Van, to improve soil water-physical properties and increase winter wheat yields in rain-fed areas. Methods: Laboratory and field experiments were conducted from 2021 to 2024. Laboratory experiments assessed the effects of polymer doses on hydraulic conductivity, maximum field moisture and water-holding capacity in soils with different textural compositions. Field experiments examined winter wheat yields in response to different doses of polymers and fertilizers, applied separately and in combination. Result: Aquasource (100-300 kg ha-1) and Van (1,000-2,000 kg ha-1) increased soil hydraulic conductivity by 20-47%. In light-clay soils, Aquasource (100-150 kg ha-1) and Van (1,000-1,500 kg ha-1) increased maximum field moisture by 8.4-8.6% and 8.0-10.5%, respectively. In heavy and medium loamy soils, the application of 300 kg ha-1 of Aquasource and 2,000 kg ha-1 of Van improved maximum field moisture by 5.0-6.5%. The optimal polymer doses, without fertilizers, were 50 kg ha-1 for Aquasource and 500 kg ha-1 for Van, resulting in a 21.5% and 38% increase in wheat yield, respectively. When combined with fertilizers, yields increased by 22.0-48.0%. These findings suggest that these polymers can significantly improve soil properties and enhance crop yields, promoting sustainability in rain-fed regions.