Evaluating and modeling the efficacy of Stipagrostis plumosa for the phytoremediation of petroleum compounds in crude oil-contaminated soil

ABSTRACT

This study focused on using Stipagrostis plumosa for phytoremediation to eliminate total petroleum hydrocarbons (TPHs) and heavy metals (HMs) like cadmium (Cd), chromium (Cr), lead (Pb), and nickel (Ni) from oil-contaminated soil. Conducted over six months at a field-scale without artificial pollutants, soil samples were analyzed using gas chromatography‒mass spectrometry (GC‒MS) for TPHs and inductively coupled plasma-optical emission spectroscopy (ICP‒OES) for HMs. Results after six months revealed that plots with plants had significantly higher average removal percentages for TPHs (61.45%), Cd (39.4%), Cr (46.1%), Pb (41.5%), and Ni (44.2%) compared to the control group (p <0.05). Increased microbial respiration and bacteria populations in planted plots indicated enhanced soil microbial growth. Kinetic rate models aligned well with the first-order kinetic rate model for all pollutants (R² >0.9). Overall, the study demonstrates that S. plumosa can effectively reduce TPHs and HMs in oil-contaminated soil, making it a promising option for pollutant absorption.

KEYWORDS:

• Heavy metals
• kinetic rate modeling
• hytoremediation
• Stipagrostis plumosa
• total petroleum hydrocarbons

Acknowledgements

The authors would like to express their sincere appreciation to Kashan University of Medical Sciences for their financial support. The authors confirm that the field studies on the plants were carried out according to the instructions of the “Iranian Forestry and Rangeland Research Institute”. We also follow the IUCN Policy Statement on Extinction-Risk Species Research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Bahador Nemati: Methodology, Conceptualization, Investigation, Writing – original draft. Hossein Akbari: Methodology, statistical analysis. Rouhullah Dehghani and Saeid Fallahizadeh: Methodology, Writing – review & editing. Gholamreza Mostafaii and Mohammad Mehdi Baneshi: Methodology, supervision, writing – review & editing.

Data availability statement

Data supporting the findings of this study are available from the corresponding author.

Ethical approval

All authors have read, understood, and have complied as applicable with the statement on “Ethical responsibilities of Authors” as found in the Instructions for Authors.

Additional information

Funding

This research was supported by Kashan University of Medical Sciences (KAUMS) in Iran, with grant number [400051] and ethics code “IR.KAUMS.MEDENT.REC.1400.063”.