Phytoremediation of crude oil-contaminated sediment using Suaeda heteroptera enhanced by Nereis succinea and oil-degrading bacteria

NOVELTY STATEMENTOur study attempted to investigate the stimulatory effect of a promising phytoremediation strategy consisting of Suaeda heteroptera (S. heteroptera), Nereis succinea (N. succinea), and oil-degrading bacteria for cleaning up TPH in spiked sediment. Planting S. heteroptera can greatly increase sediment TPH removal, and its removal was enhanced greater after inoculation with oil-degrading bacteria and/or N. succinea. Moreover, the promising phytoremediation strategy developed in the current work can serve as an efficient, novel approach to removal TPH in sediment/soil. In our opinions, these findings provide insights into the assessment of their ecological risks in the environments that are of interest to broad readership of International Journal of Phytoremediation. A 150-day experiment was performed to investigate the stimulatory effect of a promising phytoremediation strategy consisting of Suaeda heteroptera (S. heteroptera), Nereis succinea (N. succinea), and oil-degrading bacteria for cleaning up total petroleum hydrocarbons (TPHs) in spiked sediment. Inoculation with oil-degrading bacteria and/or N. succinea increased plant yield and TPH accumulation in S. heteroptera plants. The highest TPH dissipation (40.5%) was obtained in the combination treatment, i.e., S. heteroptera + oil-degrading bacteria + N. succinea, in which the sediment TPH concentration decreased from an initial value of 3955 to 2355 mg/kg in 150 days. BAF, BCF, and TF confirmed the role of N. succinea and oil-degrading bacteria in the amelioration and translocation of TPHs. In addition, TPH toxicity of S. heteroptera was alleviated by N. succinea and oil-degrading bacteria addition through the reduction of oxidative stress. Therefore, S. heteroptera could be used for cleaning up oil-contaminated sediment, particularly in the presence of oil-degrading bacteria + N. succinea. Field studies on oil-degrading bacteria + N. succinea may provide new insights on the rehabilitation and restoration of sediments contaminated by TPHs.

Automated summary

This study investigated the stimulatory effect of a promising phytoremediation strategy on the cleanup of TPH-contaminated sediment. The results showed that planting S. heteroptera can effectively remove TPH from sediment, and this removal is enhanced by the addition of oil-degrading bacteria and/or N. succinea. Furthermore, the presence of N. succinea and oil-degrading bacteria can alleviate the TPH toxicity of S. heteroptera.