Impact of the different sources of mulch on soil chemical properties of an Ultisol in Umudike, South East Nigeria

This research was conducted at the Teaching and Research Farm of Abia State University Umudike, to evaluate the impact of different sources of mulch on soil chemical properties of an Ultisol in Umudike, South East Nigeria. The experiment comprised of five (5) treatments namely, Control = 0t/ha, R1 – Ricemill waste 10/ha, R2 - Ricemill waste 15/ha, S1 - Sawdust =10t/ha, S2 - Sawdust = 15t/ha. The experiment was laid out in a Randomized Complete Block Design (RCBD) with the treatments replicated three (3) times to give a total of fifteen (15) plots. Raw data obtained was analyzed using analysis of variance (ANOVA) and significant means were separated using Fisher least significant difference (F-LSD) at probability level of (P<0.05). The results obtained showed that total exchangeable acidity significantly (P<0.05) reduced in mulched plots compared to the control. Soil pH, available phosphorous, total nitrogen, organic carbon and exchangeable cations of mulched plots were significantly (P<0.05) higher than the control. Similarly, Effective cation exchange capacity (ECEC), percentage base saturation and C: N ratio was significantly (P<0.05) higher when compared with the control. Sawdust application at the rate of 15t/ha significantly (P<0.05) increased pH, organic carbon, available phosphorous, effective cation exchange capacity (ECEC), percentage base saturation and C: N ratio compared to control and ricemill at 15t/ha. However, Ricemill waste at 10t/ha and 15t/ha significantly (P<0.05) increased soil total nitrogen and sodium (Na) content compared to control and sawdust at different rates. Ricemill waste and sawdust mulch positively influenced soil chemical properties and could be recommended for enhancement of soil chemical properties in Umudike South East Nigeia.