Vol. 7, Issue 3, Part A (2025)

Plant and soil are major parts of terrestrial ecosystem, and variations in vegetation cover may alter the properties of soil, mostly the topsoil. Hence, this study investigated the influence of trees on soil physiochemical properties. The study was done in the forestry and wildlife arboretum of the University of Port Harcourt, Nigeria, and involved five tree species. Soil samples were gotten at two depths under the selected tree species, and their physiochemical properties were analyzed. Analysis of variance was performed on the data obtained, and the last significant difference at 5% was employed to separate the means. Results indicated that; sand particles ranged from 78%-81% at 0-15 cm depth, bulk density ranged from 1.29-1.70 gcm-3 at 0-15 cm depth and 1.59-1.75 gcm-3 at 15-30 cm depth, the maximum pH (5.6) was recorded under Gmelina arborea at 15-30 cm depth while the lowest pH (4.6) was recorded under Tectona grandis and Anona moricata at 15-30 cm depth respectively, the maximum total nitrogen (44.5 g/cmol) was recorded under Gmelina arborea and Irvingia gabonensis at 0-15 cm depth while its lowest value of 22.3 g/cmol was recorded under Anona moricata at 15-30cm depth, magnesium at 0-15 cm depth ranged from 2.15-3.30C mol kg-1 and 1.20-1.45C mol kg-1 at 15-30 cm depth, among others. It was concluded that selected tropical tree species in the Arboretum exerted some level of influence on soil physiochemical properties in the following decreasing order; Gmelina arborea > Nauclea dedirrichii > Tectona grandis > Irvingia gabonensis > Anona moricata.