Phytoremediation of Diesel Oil Polluted Soil by Fluted Pumpkin (Telfairia Occidentalis Hook F.) in Uyo, Niger Delta Region, Nigeria

摘要

Phytoremediation is an emerging technology for cleaning contaminated soils. In this study, the effect of fluted pumpkin (Telfaira occidentalis Hook F.) on the degradation of petroleum hydrocarbon in a diesel oil contaminated soil was investigated. Fluted pumpkin seeds were planted in each treatment (0.00, 1.11, 1.59, 2.50 and 3.06%) for a period of 18 weeks. The following parameters were determined: germination percentage, length of vine, number of leaves per vine, leaf yield and the dry weight of leaves and vines on the 3rd, 6th, 9th, 12th and 15th weeks after planting (WAP). Total petroleum hydrocarbon (TPH) was determined on the 2nd and 18th weeks after oil pollution (WAOP). Total bacterial and fungal counts were determined on the 3rd, 6th, 9th, 12th, 15th and 18th WAOP. The results demonstrated that diesel affected soil depressed seed germination. Length of vine and number of leaves per vine were observed to increase from 3rd to 15th WAOP. Leaf yield increased from 3rd to 9th WAOP and thereafter declined from 12th to 15th WAOP. The results further revealed reduction in dry matter of leaves as concentration of oil increases, whereas dry weight of vines increased with increasing oil pollution. The result also demonstrated that fluted pumpkin stimulated total bacterial and fungal number. Total petroleum hydrocarbon (TPH) removal in the polluted soil was observed to be 86.53, 94.38, 92.80 and 92.97% in 1.11, 1.59, 2.50 and 3.06% concentration respectively. Thus, fluted pumpkin has proved to be efficient for removal of TPH from oil-contaminated soil. Keywords: Phytoremediation, diesel oil, fluted pumpkin, contaminated soils, petroleum hydrocarbon