African Journal of Biotechnology

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Yield of maize (Manoma spp) affected by automobile oil waste and compost manure

PI Ezeaku, BO Egbemba


The study is aimed at evaluating the effects of compost manure on the remediation of automobile oil waste polluted soils, and on the yield parameters (plant height, leave surface and dry matter weight) of maize (Manoma spp). Analyses of soil samples of contaminated and uncontaminated sites collected with core samplers at 10 cm depth and auger samplers at two depths (surface, 0 – 20 cm; subsurface, 20 – 40 cm) were examined for chemical and physical properties, including poly aromatic hydrocarbons. Polluted soils were biotreated for testing maize in a greenhouse. Soil physical and chemical properties decreased with depth and were significantly (P<0.05) affected by contamination. Decreases in soil poly aromatic carbon from original concentration were observed. Phyto-assessment showed that maize seedlings bio-accumulated heavy metals in polluted soils, which made their survival rate marginal relative to those grown in uncontaminated soils. Soil amendment with compost manure significantly (P<0.05) improved soil properties and maize yield variables. Ecological risk factor (HQ>1) of heavy metals (for example; Zn, Cu, Mn) was high for maize cultivation. Paradigm approach emphasizing sustainable biological soil systems management is desired. Particularly, bioremediation of oil polluted soils using organic materials, and siting of mechanic villages several kilometers away from major land uses (residential houses, farm lands, and usable water bodies) are important for protecting the soil resources for agricultural purposes, and to ensuring environmental sanity and sustainability.

Keywords: Automobile oil wastes, phytotoxicity, soil amendment, poly aromatic carbons

African Journal of Biotechnology, Vol 13(11), 1250-1256
AJOL African Journals Online