Organic content of all groups at the commencement of experiment of each of the first and third phase was not significantly different (P > 0.05), with average values of 1.70 ± 0.05% to 1.79 ± 0.07% ( Table 3) and 1.47 ± 0.02% to 1.56 ± 0.06% ( Table 4), respectively. A significant increase (P < 0.05) in organic matter was, however, observed at the end of the experiment in the first and third phase, with values of 4.13 ± 0.06% to 4.56 ± 0.07% and 4.17 ± 0.13% to 4.64 ± 0.04%, respectively.