Abuja Journal of Agriculture and Environment (AJAE)

DISTRIBUTION OF SOME METALLIC MICRONUTRIENTS (COPPER, ZINC, IRON AND MANGANESE) ALONG TWO TOPOSEQUENCES SITUATED IN AN ALFISOL IN ABUJA, SOUTHERN GUINEA SAVANNA ZONE OF NIGERIA
Author(s): Barnabas, I.M., Wapa, J.M. and Olowookere, B.T.
Volume/Issue: Volume 1 , Issue 2 (2021)

ABSTRACT:

Micronutrients are essential nutrients required by plants in small quantities. A study was carried out to examine the distribution and availability of Cu, Zn, Fe and Mn in the soil along two opposite toposequences dissected by a seasonal stream in the teaching and research farm of University of Abuja. On each side of the toposequences, three profile pits were dug (upper, middle and lower slope positions). Samples were collected and analysed routinely as well as for some micronutrients. The extractable micronutrients were extracted following standard procedures and read using AAS (UNICAM 969 Model). The results showed that soil texture was generally sandy loam at the surface and sandy clay loam, clay loam and clay in the sub surface horizons. Soil pH was strongly acidic at the surface (5.2 – 5.8) and very strongly to strongly acidic (4.8 – 5.8)in the subsurface horizons. EC was rated low to high (0.050 – 1.00 dSm). Soil organic matter was high at the surface and in the composite samples (1.11 to 2.28 g/kg). TN was low to moderate (0.149 to 0.320 g/kg),available P was equally low to moderate (12.25 to 38.50 mg/kg). All the micronutrients were very high. Mn(62.13 – 172.72 mgkg-1), Fe (42.80 – 321.30 mgkg-1) and Zn (3.16 – 25.42 mgkg-1) were rated as being very high in terms of their abundance in the soil. Cu was low to moderate (1.57 – 3.35 mgkg-1). It was considered that there was no basis for further application of any of these micronutrients to the soils. Also, the use of fertilizers with acidic residual effects should be done with caution not to increase the soil acidity and thus boost the abundance of these micronutrients to toxic levels.

KEYWORDS:

Metallic, Alfiols, Guinea, Savanna, Abuja, Nigeria