SURVIVAL AND EARLY GROWTH OF SOME SELECTED TREE SPECIES ON CRUDE OIL POLLUTED SOIL FOR PHYTOREMEDIATION

Abstract

This study was carried out to examine survival and early growth of some selected plants on crude oil polluted soil for phytoremediation. Five tree species at seedling stage were used to assess their potential for phytoremediation. The tested species are J. curcas, A. auriculiformis, Delonix regia and Cassia siamea. Crude oil polluted soil samples were randomly collected from the Atlantic coastline area of Abereke town in Ilaje local government, an oil producing area of Ondo State at two different depths (0 – 15 and 15 – 30 cm) using 8.5 cm diameter soil auger. Composite samples were collected into polythene bags, properly labeled and then transported to the nursery site in Akure, Ondo State. Five different sowing media were prepared and filled into 2 by 3 cm size polythene bags containing different treatments. The soil samples were subjected to laboratory analyses to determine their physical and chemical properties. The germinated seedlings were transplanted three weeks after sowing to the sowing media which constituted the experimental treatments. This was done by carefully removing the seedlings and transplanted in polypots containing the growing media at five replicates. Watering was carried out twice a day (early in the morning and late in the evening) till the end of the experiment (3 months). The physical and chemical characteristics of the sampled crude oil polluted soil at the two depths were found to be higher at the 15 to 30 cm with exception of Ca, clay and silt. The effects of growth media on growth parameter of J. curcas had it values ranged from 0.00 – 20.08 cm, 0.00 – 1.14 cm, 0.00 – 99.78 cm2 and 0.00 – 5.00 for height, collar diameter, leaf area and leaf number respectively. The effects of