Study of soil salinization in agricultural areas within the irrigated perimeters of the Ouargla Region, Southeastern Algeria

The use of groundwater irrigation is essential for most crops in arid regions, where evaporation is high and rainfall is scarce and irregular. However, this practice can have long-term detrimental effects on water quality and promote the development of processes such as sodification, salinization, or alkalization of soils. This work was conducted in representative irrigated agricultural perimeters in the Ouargla region using groundwater. The objective of this study is to assess the impact of using this water for irrigation. In this context, a detailed diagnosis of the current situation of these perimeters was carried out through a sampling campaign and analysis of water and soil. The physical and soil characterization showed that the soil in the studied perimeters is sandy, indicating a filtering and draining soil with high permeability but low retention capacity. The soil is also low in organic matter. Chemical characterization of the soil indicates that the pH values for different samples are close to those of the irrigation water. Electrical conductivity (EC) ranges from 0.24 to 2.85 dS/m. Through this study, a salt transfer process between irrigation water and soil was observed. The qualitative study of water used for irrigation purposes shows that these resources have very excessive mineralization, expressed by electrical conductivity ranging from 4140 µS/m to 6520 µS/m. This conductivity poses a significant risk of alkalization.