摘要：Top soil (0-15cm) samples were collected from six wastes impacted soils and a Control within Akwa Ibom State, Nigeria and assessed for the total contents, different forms and bioavailability of iron (Fe), co pper (Cu), chromium (Cr) and zinc (Zn) in the area. Results obtained showed the following ranges (mg/kg) for total elements: 1052.10 – 1664.54 Fe; 1.165 – 9.862 Cu; 1.072 – 1.815 Cr and 29.411 – 51.412 Zn, the distribution of all the elements skewed to the right except Zn. These elements were also found to be below their minimum concentrations recommended by FAO/WHO, thus indicating their deficient status in the area. Speciation results revealed that all the essential elements examined existed mostly in the residual fraction thereby reducing their bioavailability in the study area. Bioavailability of these elements ranged as follows: 14.68 - 16.49% Fe; 8.75 – 21.18% Cu; 15.90 – 18.86% Cr and 17.26 – 19.43% Zn. These results show that copper was the most available element while iron was the least available. BCR speciation results also indicated mean percentage recovery of the elements as Fe (97 %); Cu (97%); Cr (86%) and Zn (98%). A standard reference material (SRM 2710a Montana 1 soil) was also analyzed for these elements and results obtained were in agreement with the ones in literature thereby validating results and speciation techniques used in this study. Generally, this research has observed that plants yield and fertility may be seriously affected by the scarcity of these essential elements within the study area.
