E. (Elisa) Pais Pellizzer

PhD thesis: Microbial bioremediation of petroleum hydrocarbons in soil microcosms (2025)

Petroleum contamination in soil is a serious environmental problem due to the toxic and long-lasting nature of oil-based compounds. As global oil production continues to grow, finding effective and sustainable ways to clean up polluted soils is more important than ever. One promising method is microbial bioremediation, which uses the natural ability of microorganisms to break down harmful substances. This study focused on improving our understanding of how microbes help clean petroleum-contaminated soils over longer periods, something that has been less explored in past research.
The research had three main goals: to develop a group of helpful microbes (a microbial consortium) for cleaning soil, to test different treatment strategies under controlled conditions, and to explore how microbial communities change over time during the clean-up process. Fungal species were selected for their ability to work well together. These fungi were applied in various treatments including natural processes, added nutrients, added microbes, and a combination of both.
The results showed that using both added nutrients and microbes was the most effective in breaking down harmful petroleum compounds and reducing soil toxicity. Over time, certain rare microbial species became more active, playing key roles in the clean-up process. The study also found that different microbes respond in unique ways depending on the treatment, revealing how complex and dynamic microbial communities are.
Overall, this research highlights the importance of understanding microbial behavior for improving bioremediation efforts and developing more effective and lasting solutions for polluted environments.