Movement of potassium in an Ustochrept soil profile in a long-term fertilizer experiment

Abstract

SummaryDownward movement of potassium (K) was studied in the soil profiles of a longterm fertilizer experiment. The distribution of different forms of K and the percentage K saturation of the CEC of soil, at various depths of the differentially treated plots, indicated that applied K moved down to 75 cm depth in the high-K plots after nine cycles of a maize-wheat-cow peas crop rotation. However, movement of K was not noticed in plots not given K fertilizers. Plant uptake of K far exceeded the amounts of applied K. Application of K fertilizer reduced the release of K from the non-exchangeable reserves. Forms of K and the percentage K saturation of the CEC of soils were significantly correlated.