Biodegradable microplastics aging processes accelerated by returning straw in paddy soil

• Published in: The Science of the total environment 2024-10, Vol.945, p.173930, Article 173930
• Main Authors: Huang, Junxia, Feng, Yanfang, Xie, Huifang, Liu, Xiaobo, Zhang, Qiang, Wang, Bingyu, Xing, Baoshan
• Format: Article
• Language: English
• Subjects: Aging process; agricultural management; Agriculture - methods; biodegradability; Biodegradable microplastics; Biodegradation, Environmental; biofilm; dissolved organic matter; environment; enzyme activity; hydrophilicity; microplastics; Microplastics - analysis; organic fertilizers; Oryza; Paddy soil; paddy soils; peptidase K; plastic film; Polyesters; polylactic acid; roughness; sewage sludge; Soil - chemistry; soil bacteria; Soil Microbiology; Soil Pollutants - analysis; soil water; straw; Straw return
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.173930

Biodegradable microplastics (MPs) have been released into agricultural soils and inevitably undergo various aging processes. Straw return is a popular agricultural management strategy in many countries. However, the effect of straw return on the aging process of biodegradable MPs in flooded paddy soil, which is crucial for studying the characteristics, fate, and environmental implications of biodegradable MPs, remains unclear. Here, we constructed a 180-day microcosm incubation to elucidate the aging mechanism of polylactic acid (PLA)-MPs in straw-enriched paddy soil. This study elucidated that the prominent aging characteristic of PLA-MPs occurred in the straw-enriched paddy soil, accompanied by increased chrominance (76.64–182.3 %), hydrophilicity (2.92–22.07 %), roughness (33.12–58.01 %), and biofilm formation (42.12–100.3 %) for the PLA-MPs, especially with 2 % (w/w) straw return treatment (P