Background and Objective: Earthworms are important in soil formation. They maintain soil structure and fertility and can be used as indicators to evaluate various changes and impacts. Therefore, the present study was developed to investigate the effects of diesel pollutant on the population and survival of the earthworm species E.fetida in the co-vermicomposting process.
Materials and Methods: This experimental study was conducted over 90 days to investigate the effects of diesel concentration on the survival of E.fetida in the co-vermicomposting process. One kilogram of soil contaminated with diesel, vermicompost, and raw activated sludge was added to each reactor in a ratio of 0.25:0.35:1. 10. Additionally, 20 adult E. fetida were added to the reactors with diesel concentrations of 10 and 30 g/L after the adaptation process.
Results: The survival of earthworms and the formation of cocoons in reactor number 3 were higher than in other reactors. Additionally, the amount of diesel removal in reactor number 3 (diesel concentration: 10 g/kg dried soil +20 E.fetida) was higher (70.5%) compared to the other reactors.
Conclusion: The results of the study showed that earthworm reproduction is more sensitive than survival or weight change to higher concentrations of diesel-contaminated soil. The presence of petroleum compounds in the soil is harmful for the growth of E.fetida, and its acute effects on the production of earthworm cocoons were observed.
