INFLUENCE OF CASSAVA MILL EFFLUENTS ON SOIL MICROBIAL COMMUNITY

ABSTRACT The effects of cassava mill effluents on soil microbial community were evaluated by determining the total heterotrophic bacterial count of the impacted and unimpacted soil samples. Soil samples were collected from sites polluted with cassava mill effluents and also from sites unimpacted with cassava mill effluents which served as control. Standard bacteriological were used in evaluating the soil samples for viable microbial counts. The total heterotrophic bacterial count ranged from 3.x10* - 3.3 x10'Cfu/ml. Enumeration from soil impacted with cassava mill effluent for THB counts are lower (3.4x10* Cfu/g) compared to the control (2.0x10*). The total coliform count which ranged from (2.4x103 - 2.3x10ª Cfu/g) and i t i s also lower compared to control. The result o f the total fungal count also showed that the count from impacted soil sample (4.6x102 t o 1.4x10' cfu/g) where lower when compared to the counts from unimpacted samples (2.0x10*cfu/g). The microbial species isolated includes: Lactobacillus (28.6%), Staphylococcus spp (19%), Micrococcus spp (14.3%), Escherichia coli (14.3%), Bacillus spp (4.8%), Klesiella spp (4.8%), Salmonella spp (4.8%). Lactobacillus (28.6%) recorded the highest percentage occurrence, with Bacillus spp., Klebsiella sp and Salmonella spp presenting the joint lowest value of 4.8%. The fungal isolates are Aspergillus spp., Fusarium spp., Mucor sp., and Saccharomyces spp. This result indicates that the continuous disposal of the cassava mill effluent i n to the soil environment around the mill reduces soil microbial population .