Abstract

This study was undertaken to determine the concentrations of macro and micro elements in amaranth, roselle and kenaf as well as in their soils from six different agricultural fields in Aliero, Kebbi state, Nigeria. The highest values for the concentrations of P, Mg and Zn were observed in amaranth from site A; K, Fe and Mn from site D; Na from site E; Ca and Ni from site F; and Cu and Cd from site B. In roselle, the values for P was in samples from site C; K and Mn from site A; Na from site F; Ca, Mg and Fe from site D; and Cu, Ni and Pb from site E. Similarly, in kenaf, the values for P were in samples from site E; K, Fe, Zn and Pb from site D; Na and Ca from site F; Mg, Mn and Ni from site A; and Cu and Cd from site B. In soils of amaranth, the highest values for the concentrations of P, Na⁺ and K⁺ were in samples from site D; Mg²⁺, Ca²⁺ and Fe from site A; Zn and Mn from site E; and Ni and Cd from site C. In roselle, the values for P, K⁺, Mg²⁺, Fe and Cd were in samples from site D, Ca²⁺ from site A; Zn and Mn from site E; Na⁺ from site F; and Cu and Pb from site B. In kenaf, the values for P, Na⁺, K⁺, Mg²⁺ and Fe were in samples from site D; Ca²⁺, Ni and Pb from site C; and Zn, Cu, Mn and Cd from site E. Significant differences at a level of P<0.05 were observed in the concentration of the elements within each species of the vegetables and also within their soils. Difference in environment (site of collection) had effect on the concentration of the elements in both the vegetables and their soils. The trends observed for the elements in each species of the vegetables were different from what was observed in their soils. From the transfer factor values, the concentrations of the micro elements (except Zn and Cu) in the vegetables do not necessarily depend on their concentrations in the soil.     

Key words: Macro and micro elements, amaranth, roselle, kenaf, soils, transfer factor.