Objective This study aimed to clarify the content levels and influencing factors of medium elements in soils within tobacco-growing areas of Jiangxi Province, in order to provide a basis for rational fertilization of tobacco.

Method Sixty-nine topsoil samples were collected from 6 predominant soil types in typical tobacco-growing regions, Jiangxi Province. Key physicochemical properties of each soil type were measured, and the characteristics of exchangeable Ca, Mg, and available S were analyzed through grading classification and redundancy analysis (RDA).

Result The exchangeable Ca and Mg contents in various soil types of tobacco-growing regions were severely deficient, with average values of 1.29 cmol(+) kg⁻¹ and 0.28 cmol(+) kg⁻¹. Among different soil types, the contents of exchangeable Ca ranged from 0.43 to 4.42 cmol(+) kg⁻¹, while the contents of exchangeable Mg fluctuated from 0.11 to 0.98 cmol(+) kg⁻¹. Only 16.67% of the content of exchangeable Ca and 8.33% of the content of exchangeable Mg in purple clay paddy soils met the moderate thresholds of 4 cmol(+) kg⁻¹ (Ca) and 0.8 cmol(+) kg⁻¹ (Mg), whereas all other soil types fell below these critical levels. The average content of soil available S was 16.76 mg kg⁻¹, indicating a moderate level, but 39.61% of sampling sites were classified as extremely deficient or deficient. The coefficients of variation (CV) for available S across soil types ranged from 33.09% to 57.23%. RDA results indicated that the variation in exchangeable Ca and Mg was mainly driven by pH and cation exchange capacity (CEC), whereas soil type exerted an indirect influence by altering these two factors. Soil available S content exhibited positive correlations with organic matter and clay content. This variation was primarily attributed to parent material, with alluvial sandy loam paddy soils (derived from fluvo-aquic soil) exhibiting significantly lower clay content compared to other soil types. Soil physical properties primarily influence medium element content by improving soil pore structure, which consequently affects related soil parameters.

Conclusion Amendments such as calcium magnesium phosphate fertilizer or slaked lime can be applied to alleviate the widespread deficiency of exchangeable Ca and Mg. Organic fertilizer application can assist in improving granitic sandy loam paddy soils. Amendments such as potassium sulfate can be used in the available S-deficient area. Organic fertilizer application can also aid improvement in purple clay paddy soils and granitic sandy loam paddy soils.