Pollution Status of Selected Agricultural Farmlands in Zaria, Kaduna State, Nigeria

Abstract

The pollution status of agricultural farmland soils of Basawa, Galma, Kubanni
and Kufena in Zaria, Kaduna state, Nigeria were assessed. The samples were
collected in the dry season, digested with aqua regia and analyzed for heavy
metals using atomic absorption spectrophotometer (AAS). Physicochemical
parameter (pH, soil texture, organic matter, moisture content and electrical
conductivity) were also determined. The physicochemical parameters indicated
that pH ranged from 6.20 to 6.90, electric conductivity ranged from 0.150 to
0.600dcm. Organic matter contents ranged from 1.19 to 3.29 %, % sand (%)
ranged from 42 to 62, % clay ranged from 8 to 20 and % silt ranged 30 to 40 for
all the soils obtained from the farmlands. The textural classes of Basawa and
Galma are loam and that up Kubanni and Kufaina ware sandy loam. The result
were that the concentrations of metals in the soil ranged from 0.05 to 2.03mg/kg
for Cd; 3.98 to 43.75mg/kg for Cu; 5.85 to 33.35mg/kg for Pb and 1.95 to 6.55
mg/kg for Cr. The geoaccumulation indices (Igeo) showed that of all the metals
studied, Cadmium in Basawa farmland soil sample was the major pollutant
being moderately to highly polluted (2.1699 mg/Kg)