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Plant-soil interactions play crucial roles in facilitating invasion success, although their underlying mechanisms remain unclear particularly in tropical forest ecosystems. In this study, microbial composition, soil physicochemical properties and arbuscular mycorrhiza colonization in the root zones of two invasive species (Broussonetia papyrifera and Cedrela odorata) and two co-occurring native species (Celtis mildbraedii and Trichilia prieuriana) were compared to elucidate their roles in the spread of these invaders in the Opro River Forest Reserve in Ghana. A total of 80 plants, 80 soil cores (0-10 cm depth) and 80 fine lateral root samples were collected from 20 randomly distributed plots (50 m ×50 m each) established within the reserve for analysis. Microbial composition and arbuscular mycorrhizal colonization of the fine root samples were determined using culturing technique and microscopic examination of root fragment respectively. Results revealed no significant differences in soil microbial composition and bacteria biomass among the plant species except Aspergillus ochraceous which was found only under B. papyrifera. However, fungal load in the root zone of C. odorata was higher than those of T. prieuriana and C. mildbraedii, but comparable to that of B. papyrifera. There were no consistent effects of plant invasion on soil physicochemical properties and frequency of mycorrhizal colonization. B. papyrifera had the highest ammonification rate and intensity of arbuscular mycorrhizal colonization. These findings suggest B. papyrifera alter the soil environment differently from co-occurring plants to invade, impact and dominate in a tropical forest ecosystem.