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Pollution and over-exploitation of groundwater aquifers in Kabul Province have led to deteriorated water quality and decreased quantity. In its turn, these have caused elevation of physical, chemical, and biological contaminant concentrations in the province’s groundwater beyond national and international drinking water quality standards. The article describes the outcomes of a pilot photovoltaic reverse osmosis (PV-RO) system for drinking water treatment in Qala-e-Gulbaz Village, Kabul Province, Afghanistan. The main system’s components include PV solar panels, three dosing pumps, two alternative current pumps, two alternative-to-direct-current inverters, sand and carbon filters, two sediment filters, one ultra-violet filter, two water flow meters, and a complete water supply distribution system. The study was assisted by the Danish Committee for Aid to Afghan Refugees (DACAAR) ground monitoring well (GMW) system; quality analysis of different physical, chemical, and biological parameters of raw and filtered water samples; measuring filtered water and wastewater flow rates; determining associated limitations and pressures; as well as valuating different related expenses during cost per capita calculations. Water quality testing has shown the system’s removal efficiency of 97% for salinity, 97% for total dissolved solids, above 90% for other chemicals (anions & cations), 65.52% for turbidity, and 100% for bacteria. The plant’s mean quantity efficiency has amounted to 50%. The study highlights certain key challenges including high initial cost, significant wastewater volume, and need for professional operators leading to high operational and maintenance expenditures, with the initial system’s cost per capita of USD79.54. Therefore, under the condition of optimizing efficiency, improving wastewater management, reducing original costs, implementing training programs, and developing the necessary policy framework PV-RO water treatment systems represent a viable alternative.

Soil salinity in Central Asia negatively impacts soil structure, leading to degradation and reduced water infiltration. This not only hampers agricultural productivity but also makes the land less suitable for construction due to its high susceptibility to deformation. Environmentally friendly materials like biochar, a carbon-rich substance, show promise in reducing the deformation of saline soils. However, the mechanisms behind its effectiveness are not yet fully understood. This study aims to analyse saline clays’ dispersion and sedimentation behaviour under varying pore water salinity levels (0 % to 10%). A biochar content of 5 % was selected as it is found to be optimum for plant growth and erosion resistance. It was found from the study that the biochar increases the aggregation of soil particles and enhances flocculation, improving soil dispersion characteristics. Biochar facilitates soil particle aggregation by increasing the cation exchange capacity. At higher pore water salinity levels (5% and 10%), the sedimentation behaviour of biochar-treated soil particles deviates from expectations, showing slower sedimentation rates and lower sedimentation heights. This is because the sodium ions are adsorbed by biochar, reducing salt’s effect on dispersion and sedimentation. The results demonstrate that biochar effectively enhances the stability of saline soils and, hence, has a potential use for ground improvement in the Central Asian region.

Работа посвящена проблемам отсутствия частного инвестирования в развитие водно-энергетического комплекса Центральной Азии. Проанализированы результаты экономического развития стран Центральной Азии в период с 2000 по 2021 год. Изучены проблемы, существующие в данной отрасли, причины, которые могут оказать негативное воздействие на экономическое развитие центральноазиатского региона, а также определены точки роста экономики данных стран. Рассмотрено воздействие Афганистана на обеспечение водой стран, находящихся в низовьях реки Амударьи. Установлено, что в странах Центральной Азии инвестиции в развитие водно-энергетического сектора происходит в основном за счет государственных источников.