STABILITY AND HYDROLOGICAL MODIFICATIONS IN A TILLED SOIL UNDER SELECTED ORGANIC AMENDMENTS IN SOUTH-EASTERN NIGERIA

A 36 months study was carried out in Nsukka, south-eastern Nigeria to determine the effect of organic amendment on the stability and hydrological properties of a tilled fragile Ultisol. The experiment was of a Randomized Complete Block Design (RCBD) with three (3) organic amendments and a control replicated thrice. The soil amendments were comprised of Palm Oil Mill Effluent (PE), Palm Bunch Refuse (PR), Cassava Peels (CS) at 12 Mg/ha and No Amendment/control (NA). Results indicated that organic amendment of tilled plots significantly increased the stability of wet and dry soil aggregates compared to soil aggregates in unamended plots. The amendment of tilled soils led to increased saturated hydraulic conductivity, water sorptivity, transmissivity, steady-state infiltration rate, cumulative infiltration after 90 minutes, time to attain steady-state infiltration and water retention. However, the general trend shows that highest values were obtained when soils were under PE and CS amendments, with values in PE treated soils showing relative increment of more than 100 % compared to control.