0
Article Tier 2 Environmental Sources Sign in to save

Mixing effect of polylactic acid microplastic and straw residue on soil property and ecological function

Chemosphere 2019 377 citations

AI summary Read the abstract

A pot experiment examined effects of polylactic acid (biodegradable) microplastics and straw residue on soil microbial communities and carbon/nitrogen dynamics, finding that PLA MPs had minimal effect on bacterial diversity but interacted with carbon availability to alter microbial function. The results suggest biodegradable microplastics are not ecologically neutral in soil ecosystems.

Polymers

Microplastics have become a contaminant of increasing concern in soils. Although biodegradable plastics were considered as alternatives of traditional plastics, some evidence showed that biodegradable plastics might produce more microplastics. Until now, the effect of biodegradable microplastics on soil functions and processes, as well as microbial communities is uncertain. Based on high throughput sequencing, enzymatic activity assay and dynamic analysis of soil carbon and nitrogen, we investigated the effects of biodegradable polylactic acid microplastics (PLA MPs) on soil microbiota and related ecological processes under conditions of high or low carbon content. The results showed that PLA MPs had no significant effect on the overall diversity and composition of bacterial communities or related ecosystem functions and processes. However, co-occurrence network analysis revealed that PLA MPs impacted the interactions between constituent species, which might have legacy effect on soil bacterial communities and functions. Our data also revealed that PLA MPs could trade off the priming effect of carbon source. Our results provided an integrated picture in understanding the effects of PLA MPs on soil microbes, properties and ecological functions, which will help to further understand the effects of MPs on terrestrial ecosystems.

More Papers Like This

Article Tier 2

Aging of biodegradable plastics alters soil aggregate stability and organic carbon through shifts in microbial community composition

AI summary Read the abstract

Researchers examined how polylactic acid (PLA) drinking straw fragments at varying concentrations alter soil aggregate stability, organic carbon, and microbial communities, finding that moderate concentrations initially boosted aggregate stability and microbial diversity before higher concentrations caused decline, while PLA degradation enriched potentially pathogenic bacteria.

Article Tier 2

Effects of biodegradable microplastics and straw addition on soil greenhouse gas emissions

AI summary Read the abstract

Researchers tested how biodegradable microplastics made from polylactic acid (PLA) affect greenhouse gas emissions from soil, both with and without added crop straw. They found that high concentrations of PLA microplastics significantly increased carbon dioxide emissions while decreasing nitrous oxide emissions, suggesting that even biodegradable alternatives to conventional plastic mulch films can meaningfully alter soil chemistry and gas cycles.

Article Tier 2

Biodegradable microplastics decreased plant-derived and increased microbial-derived carbon formation in soil: a two-year field trial

AI summary Read the abstract

A two-year field experiment compared the effects of conventional (polypropylene) and biodegradable (polylactic acid, PLA) microplastics on soil carbon cycling in agricultural soil. Researchers found that while neither plastic type changed total soil carbon levels, PLA microplastics significantly reduced plant-derived carbon (lignin) by 32% while boosting microbial-derived carbon, suggesting that "biodegradable" plastics still meaningfully alter soil biology and chemistry. This matters because it challenges the assumption that biodegradable plastics are environmentally benign once they break down in farmland.

Article Tier 2

Response of peanut plant and soil N-fixing bacterial communities to conventional and biodegradable microplastics

AI summary Read the abstract

Researchers tested how conventional plastics (polyethylene and polystyrene) and a biodegradable plastic (polylactic acid) affect peanut plant growth and nitrogen-fixing soil bacteria. They found that while none of the plastics reduced plant biomass, the biodegradable PLA at high doses dramatically altered soil nitrogen levels and bacterial community composition. The study suggests that biodegradable plastics may not be as harmless to agricultural soil ecosystems as commonly assumed.

Article Tier 2

Insights into soil microbial assemblages and nitrogen cycling function responses to conventional and biodegradable microplastics

AI summary Read the abstract

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.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper