EFFECTS OF CASSAVA EFFLUENT ON SOIL MICRO ORGANISMS

EFFECTS OF CASSAVA EFFLUENT ON SOIL MICRO ORGANISMS

CHAPTER ONE

• Introduction
  • Background of the study

There have been increases in environmental awareness and concern about pollution for many years now. Almost any substance present either in excess or less in the wrong source in environment at the wrong time causes pollution. Soil formation is the result of the combined action of weathering and colonization of geological material by microbes (Willey et al, 2008) soil has many layers, with the topsoil being the most productive the biological component of the topsoil consist mainly of soil organisms especially microorganisms which are key players in the cycling of nitrogen, sulphur and phosphorus and decomposition of organic residues. They affect nutrient and carbon cycling on global scale (Bunning and Jimenez, 2003). The topsoil receives the greatest impact from pollutants

One common human activity that may result to environmental degradation is cassava processing activities are now extensively carried out in many rural and urban centres in Nigeria and elsewhere. Cassava (Manihot esculenta) and its waste water have been reported to be toxic and poisonous (Okezie and Koikowski, 1983). The toxicity of cassava and its waste water is basically associated with its pH and cyanide content. Cassava waste water has been observed to be highly acidic with pH as low as 2 – 6 (ESCAP, 1992).

Cassava waste water nay therefore influence the acidity of soil when large amounts are added to the soil. It is reported that when soil PH is too acidic, plants cannot utilize Nitrogen Sulphur and Phosphorus and other nutrients (Spector, 2001). Soil pollution by this cassava effluent causes imbalance in soil flora and fauna, which leads to reduction in soil fertility. This is mostly because microorganism which are involved in all nutrient cycling are destroyed. Much waste from cassava mills are generated which are usually discharged on land or into water bodies indiscriminately and this in turn affects the biota (Olorunfemi et al., 2008).

1.2     Statement of the Problem

There has been great upsurge in the production and utilization of cassava in the past few years. This has led to establishments milling engines in most environments with the consequence of an extensive ecological pollution associated with the effluent discharge. This could lead to a reduction in the soil fertility, by causing imbalance in the soil microorganism that play key role in fixing soil fertility, which in turn could lead to reduction in food supply and of course causing health problem through the accumulation of the cassava cyanide which is toxic to human. Hence, fermenting cassava effluent calls for the establishment of laws to guide the discharge of cassava waste generated.

1.3     Scope and Limitation of the study

The design of this project work is to evaluate and assessing the effect of cassava effluent on soil microorganisms. Due to time, instrument and financial constraint, this research project work is limited to soil bacteria only.

1.4     Objective of the study

The design of this project is to:

• Assess cassava effluent pollution soil
• Isolate bacteria and fungi from cassava effluent polluted soil
• Identify and characterize bacteria and fungi isolate from the soil sample