Ecological and ameliorative assessment of soil salinization in the Shirvan plain of the Kura-Araz lowland, Azerbaijan

Abstract

The Kura-Araz Lowland is one of the most important agricultural regions of Azerbaijan and plays a significant role in crop production and national food security. This study evaluates the current ecological and ameliorative status of irrigated soils in the Kurdamir and Goychay districts of the Shirvan Plain. For the first time, a comparative assessment of irrigated soils was conducted in the villages of Sor-Sor in Kurdamir District and Chakhirli and Inca in Goychay District. The salinity dynamics of the past two years were examined using six representative soil sections established in characteristic landscape and agricultural areas. Soil samples were collected from depths of 0–25, 25–50, 50–75, 75–100, 100–150, and 150–200 cm and analyzed for physicochemical properties, salinity status, and productivity-related indicators, including exchangeable (absorbed) bases. The results indicate that the soils of both districts are predominantly heavy-textured, carbonate-rich throughout the soil profile, and alkaline in reaction. Soil pH ranged from 7.18 to 7.53 in Kurdamir and from 7.04 to 8.13 in Goychay. Salinity was identified as the principal soil constraint limiting agricultural productivity in both districts. Grain yields in Kurdamir ranged from 3.0 to 5.0 t ha⁻1, while cotton yields ranged from 2.8 to 3.0 t ha⁻1. In Goychay, grain productivity ranged from 3.0 to 3.2 t ha⁻1. The findings demonstrate that irrigation-induced salinization and associated soil degradation require systematic monitoring and improved irrigation and soil-management practices to maintain soil fertility, enhance agricultural productivity, and ensure the long-term sustainability of irrigated agriculture in the Shirvan Plain.