Modelling the Influence of Incorporating Inorganic Fertilizer on the Recovery Pattern of two Agricultural Soils after Load Application

Abstract.

The effect of inorganic matter incorporated into sandy loam and sandy clay loam soils before compaction on their recovery pattern was studied in the Department of Agricultural and Environmental Resources Engineering, University of Maiduguri. The two soil textures were collected from the top 20 cm of the soil profile from the University of Maiduguri Research Farm and near Coca-Cola Bottling Company, both in Maiduguri. The inorganic matter used for the study was NPK fertilizer. The organic matter content of each of the two soil textures was found to be 0.64% for sandy loam soil and 0.71% for sandy clay loam soil. The organic matter content was thereafter raised to 0, 2, 4, 6, and 8% by weight using the NPK fertilizer. The soil-inorganic matter mixtures were compacted at three different moisture levels of 0, 12 and 18%. The loads used for compaction were equivalent static pressure of proctor hammer blow of 25 blows. Soil bulk density, penetration resistance and level of recovery of the soil-inorganic matter mixtures were measured after compaction. Compaction resulted in increased bulk density and penetration resistance. The incorporation of inorganic matter into the soils led to an increase in soil bulk density and penetration resistance irrespective of the load imposed on the soils. After compaction, more recovery was observed in the sandy loam soil than the sandy clay loam soil.