Manganese Release Kinetics In Some Calcareous Soils From The Sulaimani Governorate In Iraqi Kurdistan Region

Abstract

This study was carried out in the Sulaimani Governorate, Iraqi Kurdistan Region, to estimate manganese release kinetics in five calcareous soils including (Sharazor, Qaradagh, Bazian, Mawat, and Surdash). The highest amount of Mn release during 48 hours was least in soil Surdash (64.00 mg kg-1), while Soil Mawat exhibited the highest release (541.82 mg kg-1). The value of first order release rate constant (k1) from first order differed from 0.076 to 0.102 with a mean of (0.091 h-1). The mean values of the rate constant (a and b) from the power function model were (2.128 mg Mn kg -1(h-1)b and 0.916 mg Mn kg-1)−1) respectively varied widely with the five soil. The value of second order release constant (k2) from second order model, varied from (-0.012) to (-0.005) with a mean of (-0.008 mg Mn kg-1)-1. The first order, power function, and second order were the best-fitted model used to describe Mn release process very well in the investigated soils.