Journal of Biology and Nature

Research was carried out in a study site in Port Harcourt, Rivers State to investigate the effect of Leaf-litter and Hydrogen peroxide as agents of amendment in crude oil polluted soils. The experiment was arranged in a Block Design with various levels of crude oil pollution. The experiment had 14 treatments and 5 replicates viz.T1:100 ml Crude Oil (C/O) + 100 ml Hydrogen peroxide (H₂O₂), T2:100 ml C/O + 100 g Leaf litter (l/l), T3:200 ml C/O + 200 ml H₂O₂, T4:200 ml C/O + 200 g l/l, T5:300 ml C/O + 300 ml H₂O₂, T6:300 ml C/O + 300 g l/l, T7:400 ml C/O +400 ml H₂O₂, T8:400 ml C/O + 400 g l/l, T9:500 ml C/O + 500 ml H₂O₂, T10:500 ml C/O + 500 g l/l, T11:no pollution + 500 ml H₂O₂, T12:no pollution + 500 g l/l, T13:500 ml C/O + no amendment and T14: (no pollution+no amendment) control. A total of 70 experimental bags of 10kg capacity were filled with 10kg soil and polluted with C/O at different levels, organic and inorganic materials were applied at 1 month interval after pollution for 4 months. Soil samples were analysed for the physico-chemical properties for six times; before, after pollution, 1 month after amendment for 4 months. Results of soil analysis showed very high levels of Total Hydrocarbon Content (THC) with values for T9 (501.16, 500.94, 500.54, 422.2), T10 (501.52, 500.9, 500.94, 415.4) and T13 (500.0, 509.0, 480.0, 430.0, 190.0) had the highest total hydrocarbon content in month 1, 2 and 3. Values reorded for T9 and T10 showed no significant difference. However, T1 (151.32, 151.06, 151.02, 145.62, 125.36) and T2 (151.66, 150.4, 150.7, 128.72, 124.96) had the least THC in all the months. THC greatly reduced at 4 months in all the treatments which could be due to amendments and natural environmental factors.TPH increased in all the treatments according to the various levels of pollution with T9, T10 and T13 recording the highest values (22.2-23.1) compared to the values of the other treatments T1-T8 (1.5-15.3). T11, T12 and T14 (control) recorded the least TPH values in all the treatments (0.00- 0.5). TPH values greatly reduced on 4 months after remediation (1.2-1.5). The result showed that TPH reduced in the soil upon the introduction of both leaf litter and hydrogen peroxide as amendments to the polluted soil. From the results as shown below, CEC increased on all the petroleum hydrocarbon contaminated soils upon introduction (463-655) with T9, T10, and T13 having the highest CEC upon simulation of pollution (651, 655 and 637) respectively an indication that the addition of these amendments reduced the cation exchange capacity.