A Study on the Effects of Cassava Processing Wastes on the Soil Environment of a Local Cassava Mill

Abstract

This study examines the effects of cassava processing wastes on the soil environment of a local cassava mill in Ekiadolor, Ovia North East Local Government Area of Edo State, Nigeria. Microbial, physicochemical and mineral compositions of fresh cassava effluent, cassava effluent from waste pit, soil around the cassava mill (soil 1) and soil samples 100 m away from the mill (the control, soil 2) were determined. Soil 2 had the highest microbial count of 3.52 × 10 5 cfu/ml. The microbial species isolated included Klebsiella aerogenes, Bacillus subtilis, Lactobacillus plantarum, Staphylococcus aureus, Lactobacillus delbrueckii, Fusarium solani, Aspergillus niger and Saccharomyces cerevisiae. The occurrence of the isolated microorganisms was lowest in soil 1 with 37.5%. Fresh cassava effluent was the most acidic with pH 3.2 and cassava effluent from waste pit had the highest cyanide content of 53.52 mg/l. The mineral contents (Ca, Mg, Na and K) of the fresh cassava effluent, effluent from waste pit and soil 1 were significantly lower (p<0.05) than the control. The heavy metals (Fe, Zn, Mn, Al, Pb and Cu) were significantly higher in soil 1 when compared with soil 2. Nitrate and phosphate contents were high in all the samples except the control. The continuous disposal of the cassava processing wastes in the soil environment around the mill and into a waste pit has reduced the soil quality leading to environmental degradation.

Geoelectrical and Physicochemical Characterization of Groundwater Contamination around a Cassava Processing Factory in Ogbomoso, Southwestern Nigeria

“…The rise in the cultivation of cassava to meet the huge global demand for domestic, industrial and export purposes has led to increase in the need for cassava processing and subsequent location of numerous cassava processing factories [1]. The cassava processing industry provides employment and revenue for 30% of Nigeria's informal sector [2].…”

Untitled

“…Cassava wastewater has been observed to be highly acidic, with pH as low as 2.6 (Izah et al 2017). Also, Obueh and Odesiri-Eruteyan (2016) reported the pH of fermenting cassava to be between 5.5 and 6.3. Cassava wastewater may therefore influence the acidity of soils when large amounts are added to the soil.…”

Utilization of cassava peel waste as an organic fertilizer to build a sustainable cassava production center

“…According to Sriyana and Nasita 2019, the percentage of outer skin waste is 0.5-2% of the total weight of fresh cassava and 8-15% of inner skin waste. The process of decomposition of cassava peel waste is very disturbing to the environment because it creates an unpleasant odor, has the potential to release methane gas so that it pollutes the air and becomes a breeding ground for plant-disturbing organisms or human health (Obueh and Odesiri-Eruteyan 2016;Aisien and Aisien 2020;Yuhanna et al 2021).…”