We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Effects of different microplastics on the physicochemical properties and microbial diversity of rice rhizosphere soil
Summary
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.
Biodegradable plastics, as alternatives to conventional waste plastics, are increasingly applied across various fields. However, the ecological risks associated with the widespread use of biodegradable plastics remain unclear. Additionally, biodegradable plastics tend to age in the environment, leading to changes in their physicochemical properties. The ecological risks brought by the aging of microplastics have also been scarcely studied. In this study, we selected conventional microplastics (PE-MPs), biodegradable microplastics (PLA-MPs), and aged biodegradable microplastics (aging-PLA-MPs) to explore their effects on the rhizosphere soil environment of rice. The results showed that microplastics reduced the soil N and P content, with PE slightly increasing the DOC content, while PLA and aging-PLA significantly increased DOC by 21.13 and 24.04%, respectively. Microplastics also decreased soil enzyme activity, with aging-PLA having a somewhat stimulatory effect on enzyme activity compared to PLA. Furthermore, microplastics reduced the soil bacterial diversity index and altered the community structure of dominant bacterial species, with DOC content and FDA hydrolase being the main factors influencing the soil bacterial community. Bacteria were most sensitive to PLA, and the stability of the bacterial microbial network structure decreased, although aging reduced the negative impact of PLA on the bacterial community. This study contributes to our understanding of the ecological risks posed by biodegradable plastics and their aging processes on the environment.