ASSESSMENT OF SOIL QUALITY IMPROVEMENT UNDER TEAK AND ALBIZIA

Abstract

This study was conducted to assess the quality of soil in terms of soil nutrients and other physico-chemical properties under Tectona grandis and Albizia lebbeck plantations. Systematic sampling was used to collect soil samples diagonally at eight spots in each plantation and their adjacent non-tree fields as controls. The samples were collected from soil depth of 0 to 20 cm in both plantations and controls and analyzed for pH, % of Organic carbon (O-C), % of Nitrogen (N), available Phosphorus (P) and Bulk density (Db). The study revealed that the mean levels of N, O-C and P under the T. grandis plantation were higher than its control plot. However, there was no significant difference in the level of N except for the O-C and P. Also, the pH and Db under the T. grandis were lower than its control plot but there was no significant difference between them. There was significant difference in the levels of N, O-C and P under the A. lebbeck plantation and its control plot. The N, O-C and P were higher under the A. lebbeck plantation compared to its control plot. The pH and Db were lower under the A. lebbeck plantation compared to its control plot. However, the differences were not significant. In general, A. lebbeck added more N and O-C to the soil compared to T. grandis. Also, the T. grandis added more P to the soil when compared to the A. lebbeck; however, the difference was not significant. It is therefore, recommended that A. lebbeck and T. grandis should be used for agro forestry practices particularly, where the soil needs some level of improvement in nitrogen and phosphorus respectively.