Biodegradable polylactic acid microplastics rewire the soil food web by impeding amoebae predation.

Polylactic acid microplastics significantly disrupt soil amoebae behavior and microbial networks, impairing their ecological functions and soil health indicators.

• Why it matters: Understanding the ecological impacts of biodegradable plastics like PLA is crucial as their use increases, yet their effects during degradation are poorly characterized, risking soil ecosystem stability.
• What they did: Researchers co-cultured soil amoebae with PLA microplastics and observed particle-size-dependent changes in microbial communities, amoebae avoidance behavior, and fitness costs, including reduced spore production.
• The result: Findings reveal that PLA microplastics alter soil microbial interactions and amoebae development, highlighting their potential as bioindicators and exposing ecological trade-offs in biodegradable plastic adoption.