Heavy Metal (Cr, Mn, Fe) Contents in Soils from the Mada Rice Fields in Kedah, MalaysiaAuthor(s): Nasser Alrawiq, J. Khairiah, M. T. Latif and B. S. Ismail
The aim of the present study was to investigate the heavy metal (Cr, Mn, and Fe) contents in paddy soils of the Muda Agricultural Development Authority (MADA) in the state of Kedah, Malaysia. The study was conducted in fields using two different types of irrigation water namely, recycled (RCL) and non-recycled (N-RCL) water. The heavy metals in the soil were extracted using “the sequential extraction method”. The heavy metals were extracted from the four different soil fractions using different reagents. The results showed that the concentration of heavy metals in the studied area was in the following decreasing order: Fe > Mn > Cr. The total Fe concentration in the areas supplied with RCL water ranged from 21256.895 mg/Kg to 26915.28 mg/Kg, whereas in the areas with N-RCL water Fe concentration ranged from 16090.196 mg/Kg to 18420.457 mg/Kg. It was found that the total Mn concentrations in the areas supplied with RCL water ranged from 31.948 mg/Kg to 44.444 mg/Kg, whereas in areas with the N-RCL water, it ranged from 27.673 mg/Kg to 33.260 mg/Kg. The total Cr concentration in the areas supplied with the N-RCL water, it ranged from 14.595 mg/Kg to 19.073 mg/Kg. The results also showed that the heavy metals in the paddy soil fractions were concentrated mainly in the RR fraction. However, Mn was found to be at the highest level in the ELFE fraction. Fe was generally found to have the highest concentration in the RR fraction.