Physical and ionic characteristics in water soluble fraction (WSF) of Olomoro well-head crude oil before and after exposure to Azolla africana Desv.

The values of ionic and physical characteristics at 25, 50 and 100% water soluble fraction (WSF) of Olomoro well-head crude oil before and after exposure to Azolla africana were investigated. The WSFvalues before and after exposure to the plants showed that more ions were available after the introduction of the test plant. The increases in ionic and physical characteristics following introduction to A. africana to WSF decreased the population of the macrophyte. These changes are signs of leakage of ions from the plant cells as a result of ionic stress and thus degradation of the plants. Statistical analysis showed significant difference in heavy metal contents between WSF concentrations of Olomoro crude oil at 0.05% probability. Reduction in NO3 -, Mg++ (100%), Cl- (100%) and V ions in the growth medium (WSF) after exposure to the macrophyte was observed. This indicates uptake of these ions. The results also showed accumulation of Mg at 25 and 100% WSF in the plant tissue after exposure