TITLE:
Phytoremediation of Crude Oil Contaminated Soil with Axonopus compressus in the Niger Delta Region of Nigeria
AUTHORS:
Efe Sunday Ighovie, Elenwo Ephram Ikechukwu
KEYWORDS:
Axonopus sp.; Phytoremediation; Crude Oil; Impacted Soil
JOURNAL NAME:
Natural Resources,
Vol.5 No.2,
February
14,
2014
ABSTRACT:
The study assessed the effectiveness of carpet grass (Axonopus compressus) in the phytoremediation management of oil impacted soil in Ubeji and Alesa Eleme communities of Niger Delta region of Nigeria. To achieve this, the study employed an experimental research design that involved the use of Axonopus compressus in the management of oil-impacted soil sites of Ubeji and Alesa Eleme. This experiment lasted for four months’ period (one planting season). Axonopus sp. was used for the treatment of the crude oil impacted sites. Laboratory analysis of the soil samples was conducted to determine the effect of phytoremediation on hydrocarbon, acidity, organic matter and moisture loss in oil impacted sites. The study revealed that the use of Axonopus sp. resulted in 66% loss of hydrocarbon from crude oil-impacted soils of Ubeji and Alesa Eleme. However, there is no significant difference in crude oil loss in the soils of Ubeji and Alesa Eleme as a result of Axonopus sp. This could be ascribed to the similarities in soil properties and climate type of the Niger Delta region of Nigeria. It also showed that the growth of Axonopus sp. in the crude oil-impacted soils of Ubeji and Alesa Eleme has reduced the acidity of hydrocarbon content in soils (4.46 - 6.87 pH in Ubeji and 4.66 - 6.86 pH in Alesa Eleme) from the first day to the 90th days of experiment, and thereafter there was stabilization at the 4th month. This indicates that acidity in soil increases (lower pH) with increase in the concentration of crude oil in soils. However, the adoption of Axonopus sp. in hydrocarbon-impacted soils has increased the pH of soils, and enhanced the accumulation of organic matter and moisture content in oil-impacted soils of Ubeji and Alesa Eleme. The implication of the findings is that Axonopus sp. has the tenacity to phytoremediate hydrocarbon concentration in soil effectively in any geographical region of the world; as such, it is recommended for adoption by oil companies, government and non-governmental organization agency for the remediation of oil spill sites.