Effect of Crude Oil on the Development of White Mangrove Seedlings (Avicennia germinans) in the Niger Delta, Nigeria

Crude oil is a complex hydrocarbon whose introduction into the environment may be hazardous to aquatic and human life, and consequently a threat to natural resources. The severity of the impact of crude oil depends on a variety of factors, including characteristics of the oil itself, natural conditions such as water temperature and weather, and the sensitivities of receiving or impinging biota. As a result, various biological resources such as mangrove seedlings have different sensitivities to oil spills. The long-term persistence of oil in the environment may cause defoliation and possibly death. Recruitment of seedlings into the oiled area may also be affected. This study is designed to evaluate the acute and chronic effects of crude oil (Bonny Light) on the growth performance of mangrove seedlings in the laboratory; monitoring critical plant growth attributes such as stem height and diameter, leaf length, width and numbers of leaves (leaf production), senescence, and seedling survival, for sixteen weeks. The study revealed that mangrove seedlings responded differently in growth attributes with varying treatment. Evidence of crude oil effects were remarkably demonstrated between control and acute (Wilcoxon sign - rank t-test (1.0) > P (0.29)(0.05) and chronic (Wilcoxon sign - rank, t-test (1.0) > P (0.47)(0.05) exposure. The critical growth response by mangrove seedlings as a result of the treatments was further explained by the cluster and correspondence analyses.