Phytoremediation of crude oil contaminated soil using nut grass, Cyperus rotundus.

The aim of this study was to evaluate the efficacy of Cyperus rotundus (nut grass), that could be effective in phytoremediation of crude oil contaminated soil. A net house experiment was conducted with different concentrations (2.05, 4.08, 6.1, 8.15 and 10.2%) of crude oil-contaminated soil for 180 days. Plant growth, biomass, total oil and grease (TOG) degradation and microbial numbers were analyzed at different intervals i.e. 60,120 and 180 days in different percentages of crude oil contaminated soil. In presence of crude oil, plant biomass and heights reduced up to 26 and 21.9% respectively. Concerning TOG content in soil, C. rotundus could decrease up to 50.01, 46.1, 42.6, 38.8 and 32.6% in treatment I, II, III, IV and V respectively in vegetated pots during 180 days. In case of unvegetated pots, the reductions of TOG were 4.4, 5.6, 6.6, 7.6 and 9.6% in treatment A, B, C, D and E respectively. However, there was significant degradation (P = 0.05) of TOG in vegetated pots in comparison to unvegetated pots thereby proving the efficacy of this plant species for use in phytoremediation.