We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Discrepant responses of bacterial community and enzyme activities to conventional and biodegradable microplastics in paddy soil
Summary
Researchers compared the soil effects of conventional polypropylene microplastics versus biodegradable polylactic acid (PLA) microplastics in rice paddy soil over 41 days. Both types altered soil chemistry and bacterial communities, but they had different effects on enzyme activity, with PLA causing distinct changes to carbon and nitrogen cycling. This matters because biodegradable plastics, often assumed to be safer, still release microplastics that affect soil health and potentially food crops.
The prevalence of microplastics in soil ecosystems has raised concerns about their potential effects on soil properties. As promising alternatives to conventional plastics, biodegradable plastics have been increasingly applied in agricultural activities, which may release microplastics into the soil due to incomplete degradation. Compared to conventional microplastics, biodegradable microplastics in soil may induce different impacts on soil microbial properties, which have yet to be well studied. Through a 41-day microcosm experiment, we evaluated the differential effects of conventional (polypropylene, PP) and biodegradable (polylactic acid, PLA) microplastics on the geochemical properties, enzyme activities, and microbial community structure in paddy soil. Adding PLA or PP microplastics into soil significantly increased pH values and altered the contents of carbon and nitrogen nutrients. Exposure to microplastics significantly increased the activity of fluorescein diacetate hydrolase, but had varying effects on the activities of urease, sucrase, and alkaline phosphatase depending on microplastic types and doses. The addition of microplastics also influenced the structure of soil bacterial community, with Proteobacteria, Actinobacteriota, and Acidobacteriota being the dominant phyla. Significant differences in the genera of Pseudarthrobacter, Acidothermus, Bacillus, Aquisphaera, and Massilia were observed between treatments. Results of structural equation modeling (SEM) demonstrated that changes in soil carbon and nitrogen nutrients and pH values positively affected the bacterial community, while soil bacterial community as a whole exerted a negative impact on enzyme activities. FAPRPTAX analysis showed that the addition of microplastics altered the relative abundances of functional genes related to the metabolism of cellulose decomposition and ureolysis in paddy soil. Findings of this study clearly suggest that microplastic impacts on soil geochemical and microbial properties should be an integral part of future risk assessment and that to evaluate microplastic impacts, both the concentration and polymer type must be taken into account.
Sign in to start a discussion.
More Papers Like This
Discrepant soil microbial community and C cycling function responses to conventional and biodegradable microplastics
Scientists compared how conventional polyethylene and biodegradable polylactic acid microplastics affect soil microbial communities and carbon cycling. Researchers found that the two types of microplastics had markedly different effects, with biodegradable plastics causing more changes to microbial community structure and carbon-related gene activity. The study suggests that biodegradable plastics, while designed to be more environmentally friendly, may still significantly alter soil biology.
Effects of different microplastics on the physicochemical properties and microbial diversity of rice rhizosphere soil
Researchers compared how conventional polyethylene and biodegradable polylactic acid microplastics, both fresh and aged, affect rice paddy soil properties and microbial communities. They found that aged microplastics had stronger effects than fresh ones, altering soil pH, nutrient availability, and the composition of root-associated bacteria. The study warns that biodegradable plastics are not necessarily safer for soil health than conventional plastics, especially as they break down over time.
Insights into soil microbial assemblages and nitrogen cycling function responses to conventional and biodegradable microplastics
Researchers compared how biodegradable polylactic acid and conventional PVC microplastics affect soil bacteria and nitrogen cycling processes. They found that both types of microplastics altered microbial communities, but biodegradable plastics had distinct effects on nitrogen-processing bacteria and did not simply behave as a harmless alternative. The study suggests that switching to biodegradable plastics may change rather than eliminate the impact of microplastic contamination on soil health.
Biodegradable and conventional microplastics exhibit distinct microbiome, functionality, and metabolome changes in soil
Researchers compared the effects of conventional plastics (polyethylene and polystyrene) and biodegradable plastics (polylactide and polybutylene succinate) on soil microbial communities. They found that both types of microplastics significantly altered soil microbial composition, but biodegradable microplastics had a more pronounced impact on soil metabolic function and microbial activity than conventional ones.
Deciphering the effects of long-term exposure to conventional and biodegradable microplastics on the soil microbiome
This study compared how conventional and biodegradable microplastics affect soil microbes over long time periods and found that both types significantly changed soil microbial communities and disrupted carbon and nitrogen cycling after extended exposure. Biodegradable plastics, often marketed as eco-friendly, actually released more chemical byproducts than conventional plastics, which matters because these soil changes can affect the food we grow.