Ecology, Environment and Conservation Paper

DOES CRUDE OIL AFFECT THE PH, MOISTURE AND ORGANIC MATTER CONTENT OF SOILS

K.L. Njoku, M.O. Akinola and B.O. Oboh

Abstract

This study investigated the changes in the levels of pH, moisture and organic matter contents of soil contaminated with crude oil for 105 days.The soil moisture content increased as the days of study increased and soil organic matter content decreased as the period of study increased.The effect of days of study on the pH diminished after day 63.A high positive correlation (p = 0.621) exists between the pH of the contaminated soil and the concentration of the crude oil added to the soil and the correlation between the pH of the contaminated soils and the days of sampling is low (p = 0.238).Although a high positive correlation (p = 0.767) exists between the concentration of crude oil added to the soil and the percentage organic matter content of the soil, a negative correlation (p = -0.237) exists between the percentage organic matter content of the soil and the days of sampling.The implication of the decrease on the organic matter content with the increase in the period of study is that the coagulation of the soil due to crude oil pollution reduces as the period of the exposure of soils to crude oil pollution increases.The low moisture levels of the polluted soil indicate that due to crude oil pollution less dissolved materials will be available for plant uptake and subsequent metabolism.The pH range observed in the study implies that crude oil pollutions makes the soil to acidic thereby increasing the toxicity of the soil. The increase in soil toxicity, the less availability of materials like nutrients and the high coagulation of soil particles due to crude oil pollution are the major causes of poor growth of plants in crude oil polluted soil.