Tolerance and survival of native plants exposed to petroleum hydrocarbon-containing sludge: First step in phytoremediation

Abstract

Suitable plant species required to initially facilitate a phytoremediation process for any pollutant should be established to avoid pollutant toxicity to plants leading to inefficient phytoremediation process. The goal of this study was to search for native plants (Pennisetum purpureum, Cyperus surinamensis and Phragmites karka) that can tolerate and survive in sludge containing total petroleum hydrocarbon. Each plant species was planted in pots at a density of three plants in each pot containing 3 kg petroleum sludge. As for plant control, each plant species was planted in garden soil. Control contaminant contained petroleum sludge without plants. All pots were watered in an alternate day to ensure constant humidity during the observation period. This study was performed in a greenhouse over a period of 15 days. At the end of the exposure period, all three and two plants of P. purpureum and C. surinamensis died, respectively, with dried stalk and leaf. While P. karka ended up with one dead plant. The survival percentages were 0%, 33.3% and 66.7% for P. purpureum, C. surinamensis and P. karka, respectively, at the end of 15-day exposure period. As a conclusion, P. karka achieved the highest plant survival in the phytoremediation process of hydrocarbon based on the number of withered plants resulting in P. karka as a promising candidate for phytoremediation agent.