Ion leaching patterns in agricultural soils: insights from ion chromatographic data

The content and behavior of inorganic ions in soil play a critical role in determining soil quality, fertility, and suitability for agricultural applications. Nutrient leaching from agricultural soils is a major environmental concern, as it affects both soil fertility and groundwater quality. Accurate assessment of these components requires reliable and precise analytical methods, with ion chromatography emerging as a highly sensitive, selective, and precise technique for ion analysis in complex soil matrices. This study aimed to evaluate the leaching patterns of major inorganic ions in agricultural soils using ion chromatography. Experiments were conducted with soil samples from the University of Agricultural Sciences and Veterinary Medicine, and leachate samples were collected after rainfall events. Ion chromatographic analysis was performed using a Shimadzu two-channel instrument with non-suppressed conductivity detection, employing Allsep Anion 7u and Universal Cation 7u columns; this configuration enabled the simultaneous determination of five major anions (chloride, nitrite, nitrate, phosphate, and sulfate) and five major cations (potassium, sodium, ammonium, calcium, and magnesium) in under 20 minutes. The proposed method significantly enhances laboratory efficiency by minimizing both sample preparation and analysis time while allowing for the efficient, simultaneous analysis of multiple ions in a single run. This simple and rapid approach is well suited not only for soil quality assessments but also for broader environmental monitoring efforts, supporting the effective management of diffuse pollution sources.