For investigating salt composition, the collected soil samples in the Shirvan Plain underwent study for groundwater depth and its minerality and the soil’s granulometric composition. Soil analysis revealed a higher salt content and minerality of groundwater based on the groundwater depth and closeness to the surface. In the Shirvan Plain, the soils were considerably of sulfate type, although the amount of gypsum (CaSO₄2H₂O) exceeds 2.0% without covering a large area. The most common salt was sodium sulfate (Na₂SO₄) in slightly saline soils, sodium hydrogen carbonate (NaHCO₃), calcium sulfate (CaSO₄), and magnesium chloride (MgCl₂) in moderately saline soils, and Na₂SO₄, NaHCO₃, NaCl, and CaSO₄ in highly saline soils. The contents of NaCl, CaSO₄, Na₂SO₄ and magnesium sulfate (MgSO₄) were evident. The study further enunciated that soil salinization processes have covered a large area in the region with higher soil salt content and mineralization of groundwater. In the study area, salinization processes appeared more intense in areas where salt content was above 2.0% and the groundwater mineralization was higher than 30 g/l.

Keywords: Soil salinization, salt deposits, granulometric structures, groundwater mineralization

Key findings: In Azerbaijan, the Shirvan Plain and Ganja-Gazakh Massif sustain considerable effects from soil salinization. This article explores the key factors contributing to soil salinization in these regions, including groundwater salinity, soil characteristics, and human activities.