This study assessed the effect of sawmill effluents introduced into the soils and its impact on physiochemical and microbial composition of the soil. Topsoil samples were collected from two sawmilling sites at depths of 0m, 50m, 100m and 500m (which served as control). Physicochemical parameters such as pH, organic matter, organic carbon, and microbial composition of the soil within the milling sites were analyzed using standard methods. Soil pH values ranged from 5.04 – 6.90. The soil pH decreased with depth at both sites but became strongly acid at …m depths. The order of soil organic matter content was 0m, > 50m, > 100m > 500m. Soil organic matter in Okigwe sawmill site decreased from 4.36mg/kg in the 0m depth to 3.05mg/kg in 100m depth while the mean soil organic matter ranged from 0.86mg/kg to 2.32mg/kg in Ahiaeke site. However, mean values of organic matter across depths were significantly (p< 0.05) different from each other in both sites. ECEC of 17.96 and 10.10cmolkg-1 were obtained in the upper layer (0m) of the soils of the Ahiaeke and Okigwe sites, respectively. Although there was decrease in the ECEC values with increase in depth, the Okigwe site had higher ECEC values relative to the samples from Ahiaeke. The soil collected at 0m had more sodium (0.252mg/kg) than the sample obtained at 500m (0.174mg/kg) and 100m (0.131mg/kg) each. It could thus be inferred that the wood processing activity was impacting positively by providing sodium to the soil which is a very vital mineral pivotal for plant growth. Soil samples collected at a depth of 0m and 50m had 2.00mg/kg and 2.40mg/kg of magnesium respectively. The magnesium values obtained for soil collected at the various depths differed significantly (P<0.05) from the control samples. Nucleotide sequences of bacterial 16S rRNA gene fragments retrieved from bacterial isolates in this study were deposited in the GenBank nucleotide sequence database under accession nos. MK621199, MK621103, MK621201, MK640631, MK640622, MK640625, MK640623, MK640628, MK640630, MK621201, MK643270, MK621195, MK640785, MK640842 and MK640843 for the bacterial isolate whereas the fungal isolates were deposited with MK621199, MK621202, MK640642 and MK640638 (NCBI GenBank, www.ncbi.nlm.nih.gov). Bacterial isolates identified from the rhizosphere of soil based on the morphological and biochemical characteristics included Norcadia sp, Streptomyces sp, Rhodococcus sp and, Actinomyces sp. These are important species of microorganisms with potential for production of secondary metabolites useful in agriculture.

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