Ecological Footprint of Cassava Mill Effluent: Implications for Soil Microbiology and Physicochemical Integrity
Keywords:
Soil MicrobiologySoil Physicochemistry; Cassava Mill Effluent; Environmental Impact; Soil ContaminationAbstract
Background
Cassava processing generates large volumes of effluent that can significantly alter soil ecosystems. The discharge of untreated cassava mill effluent into the environment is a growing concern due to its potential to disrupt soil microbiological balance and physicochemical integrity.
Objectives
This study aimed to assess the ecological impact of cassava mill effluent on soil by evaluating changes in microbial diversity, abundance, and physicochemical properties, with a view to understanding the environmental and health implications of such contamination.
Methodology
Soil samples were collected from three sites (A–C), including areas impacted by cassava effluent. Microbial diversity and abundance were determined through culture-based isolation techniques. Bacterial and fungal isolates were identified and quantified. Physicochemical parameters such as pH, nitrogen, potassium, phosphorus, and heavy metal concentrations were also analyzed. Additionally, antibiotic susceptibility testing was performed on selected microbial isolates.
Results
Impacted soil showed an elevated bacterial count (7.8 × 10⁵ cfu/g) dominated by Bacillus sp. and Pseudomonas sp. (28.6%), while fungal growth was suppressed, with Penicillium sp. (27.2%) being the most prevalent among fungi. The physicochemical analysis revealed significant changes in soil chemistry, with increased nitrogen (797 mg/L), potassium (459 mg/L), and phosphorus (432 mg/L) levels. Heavy metals such as copper and iron were present in concentrations that may pose toxicity risks. Antibiotic testing indicated the presence of resistant strains, with Bacillus sp. showing resistance to several antibiotics, although Ciprofloxacin was most effective.
Conclusion
Cassava mill effluent enriches the soil with nutrients that stimulate bacterial growth but also leads to reduced fungal diversity, acidification, heavy metal accumulation, and the emergence of antibiotic-resistant microorganisms. These findings highlight the need for urgent and sustainable effluent management strategies to prevent long-term environmental degradation and protect public health.
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Data Availability Statement
Data available on request
