Microplastics in Agricultural Soils: Transport Pathways, Environmental Fate, Soil-Microbe Interactions, and Ecological Implications
摘要
Microplastics (MPs) have emerged as a significant global public health concern, drawing increasing attention in recent years due to their profound impact on terrestrial ecosystems, marine life, and public health. The increasing detection of MPs in agricultural soils poses significant environmental and human health risks due to their small size, persistence, and potential to accumulate in food webs and biomagnify across trophic levels. This review synthesizes existing literature on the sources and distribution of MPs in agricultural soils and examines their multifaceted effects on soil properties, crop yield, food chain transfer, antimicrobial resistance, and human health. We critically evaluate existing MP monitoring and analytical methods and discuss microbial bio-weathering processes mediated by bacteria and fungi, that impact MP fate in soils. Evidence indicates that MP exposure can alter the physical, chemical, and microbial characteristics of farmland, resulting in positive, negative, or negligible effects on crop production, depending on MP types, size, shape, and concentration. Agricultural soils receive MPs and plastic debris from diverse point and nonpoint sources, that degrade into progressively smaller fragments and particles, and environmental weathering processes further accelerate fragmentation. Finally, we propose future research and management priorities for MP-contaminated agricultural systems to improve understanding and mitigate MP accumulation, supporting more sustainable and resilient agro-ecosystems.
Graphical Abstract