Phytoremediation of soil contaminated with weathered petroleum hydrocarbons by applying mineral fertilization, an anionic surfactant, or hydrocarbonoclastic bacteria

Abstract

This study evaluated the effect of the application of mineral fertilization (F), the anionic surfactant Triton X-100 (TX100), or the inoculation with a hydrocarbooclastic bacterial consortium (BCons) on the growth of Clitoria ternatea during the phytoremediation of a Gleysol contaminated with weathered petroleum hydrocarbons (39,000 mg kg⁻¹ WPH) collected from La Venta, Tabasco (Mexico). The experiment consisted of a completely randomized design with seven treatments and four replications each under greenhouse conditions. The application of F (biostimulation) increased plant growth and biomass production; in contrast, TX100 only favored root biomass (11%) but significantly favored WPH degradation. Bioaugmentation with BCons did not show significant effects on plant growth. Nevertheless, the combination of biostimulation with bioaugmentation (BCons + F, BCons + TX100, and BCons + F+TX100) enhanced plant growth, hydrocarbonoclastic bacteria population, and WPH degradation when compared to treatments with the single application of bioaugmentation (BCons) or biostimulation (F).

NOVELTY STATEMENT

Application of mineral fertilization and commercial surfactant favored root biomass and degradation of weathered petroleum hydrocarbons (WPH). The reintroduction of hydrocarbonoclastic and surfactant-producer bacteria did not enhance plant growth but significantly contributed on WPH degradation from a chronically contaminated soil.

Keywords:

• Bioaugmentation
• biostimulation
• chronically contaminated soil

Acknowledgments

Special thanks to the National Council of Science and Techology (CONACYT) Mexico, for financial support to G. M-G during his PhD graduate program. Authors thank comments and suggestions provided by two anonymous reviewers, by which the manuscript was improved.

Author contributions

Authors contributed equally on the revision and preparation of the present manuscript. The corresponding and first author designed the work plan and preparation of manuscript. First author conducted the experiments as part of his graduate program. Remining authors contribute on facilitating either soil experimental samples, defining the application of surfactant, performing analytical procedures for WPH, or advising on standardization of microbial techniques.