We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Synergistic Effects of Earthworms and Plants on Chromium Removal from Acidic and Alkaline Soils: Biological Responses and Implications
Summary
Not relevant to microplastics — this study examines how earthworms and plants work together to remove chromium from contaminated soils, testing bioremediation effectiveness across different soil acidities and pollution levels.
Soil heavy metal pollution has become one of the major environmental issues of global concern and solving this problem is a major scientific and technological need for today's socio-economic development. Environmentally friendly bioremediation methods are currently the most commonly used for soil heavy metal pollution remediation. Via controlled experiments, the removal characteristics of chromium from contaminated soil were studied using earthworms (Eisenia fetida and Pheretima guillelmi) and plants (ryegrass and maize) at different chromium concentrations (15 mg/kg and 50 mg/kg) in acidic and alkaline soils. The effects of chromium contamination on biomass, chromium bioaccumulation, and earthworm gut microbial communities were also analyzed. The results showed that E. fetida had a relatively stronger ability to remove chromium from acidic and alkaline soil than P. guillelmi, and ryegrass had a significantly better ability to remove chromium from acidic and alkaline soil than maize. The combined use of E. fetida and ryegrass showed the best effect of removing chromium from contaminated soils, wih the highest removal rate (63.23%) in acidic soil at low Cr concentrations. After soil ingestion by earthworms, the content of stable chromium (residual and oxidizable forms) in the soil decreased significantly, while the content of active chromium (acid-extractable and reducible forms) increased significantly, thus promoting the enrichment of chromium in plants. The diversity in gut bacterial communities in earthworms decreased significantly following the ingestion of chromium-polluted soil, and their composition differences were significantly correlated with soil acidity and alkalinity. Bacillales, Chryseobacterium, and Citrobacter may have strong abilities to resist chromium and enhance chromium activity in acidic and alkaline soils. There was also a significant correlation between changes in enzyme activity in earthworms and their gut bacterial communities. The bacterial communities, including Pseudomonas and Verminephrobacter, were closely related to the bioavailability of chromium in soil and the degree of chromium stress in earthworms. This study provides insights into the differences in bioremediation for chromium-contaminated soils with different properties and its biological responses.
Sign in to start a discussion.
More Papers Like This
Microbial synergies in phytoremediation: A comprehensive review
Not relevant to microplastics — this is a review of how soil microorganisms (bacteria, fungi) assist plants in removing pollutants like heavy metals and hydrocarbons through phytoremediation; while the study addresses environmental contamination broadly, it does not examine microplastic pollution or its effects.
Impacts of microplastics and heavy metals on the earthworm Eisenia fetida and on soil organic carbon, nitrogen, and phosphorus
Researchers found that co-contamination by polypropylene microplastics and heavy metals (Cu, Cr, Zn) had synergistic adverse effects on earthworms and soil quality, reducing organic carbon and nitrogen levels more than either contaminant alone.
Ecological adaptation of earthworms for coping with plant polyphenols, heavy metals, and microplastics in the soil: A review
This review examines how earthworms cope with and help remediate soil pollutants including heavy metals, microplastics, and plant polyphenols. Researchers describe how earthworms use specialized gut metabolites and elevated antioxidant enzyme activity to neutralize toxic compounds, and can serve as biofilters that accumulate and transform these pollutants. The findings support the wider use of earthworm-based bioremediation as a strategy for restoring contaminated soils.
A Systematic Review on Earthworms in Soil Bioremediation
This systematic review found that earthworm-based bioremediation (vermiremediation), alone or combined with phytoremediation and bioaugmentation, effectively reduces soil contamination from heavy metals, pesticides, and hydrocarbons. The research is relevant to microplastics because earthworms interact extensively with soil microplastics, potentially fragmenting them further while also being harmed by plastic particle ingestion.
Potential strategies for bioremediation of microplastic contaminated soil
Researchers reviewed emerging bioremediation strategies for removing microplastics from contaminated soil, highlighting the roles of plants, root-zone microbes, soil animals like earthworms, and specialized bacteria and fungi that can use enzymes to break down plastic polymers into harmless compounds. While genetic engineering of microbes shows promise for accelerating degradation, the review notes that real-world application at scale still requires significant research and development.