Impact of reclamation practices on the content and qualitative composition of exchangeable base cations of the solonetz soil

Abstract

This paper shows the impact of long-term reclamation practices on the content and qualitative composition of exchangeable base cations of the solonetz soil. Based on the results of field visits and laboratory analyses, chemical and agrotechnical reclamation practices (phosphogypsum application 25 t ha-1 or 50 t ha-1, drainage pipes distance 20 m, trenching 50 cm, fertilization, soil tillage and cropping) have been applied to the solonetz soil. Analyses of cation exchange capacity (CEC) have shown that calcium (Ca+2) and sodium (Na+) cations prevailed over magnesium (Mg+2) and potassium (K+) cations in the soil exchange complex in all variants and all depths. Comparisons among variants and soil layers have shown that the contents of individual exchangeable base cations varied significantly (P ≤ 0.05). The highest changes in exchangeable calcium content were achieved to the depth of 30 cm, in both treated variants, and these changes were still higher in the variant with 50 t ha-1 of phosphogypsum. The content of exchangeable Na+ decreased by 43 % to 71% in variant I and by 23% to 64% in variant II in comparison with the control variant. The application of the reclamation practices caused changes in the composition and proportions of cations in the layers of the solonetz soil to the depth of 50 cm. When compared with CEC in the control variant, the exchangeable sodium percentage (ESP) in the treated variants decreased by 6% to 15% after fifteen years.