Micro/nanoplastics (MNPs), plastic particles and fibers with sizes ranging from nanometers (≥ 1 nm) to micrometers (≤ 5 mm) have become emerging environmental pollutants and are widely distributed across various ecosystems worldwide. These tiny plastic particles not only pose a threat to marine ecosystems, but also present new challenges to terrestrial ecosystems. However, research on terrestrial MNPs lagged behind marine studies.
In a study published in Trends in Plant Science, researchers from Xishuangbanna Tropical Botanical Garden of the Chinese Academy of Sciences and collaborators tried to fill in the knowledge gap of the uncertainty about the effects of MNPs on multi-trophic biological interactions and ecosystem functions, especially on plants and aboveground-underground (AG-BG) food webs.
Researchers presented an overview of MNPs ingestion, bioaccumulation, and their ecotoxicological endpoints on plants and the associated key AG-BG biota across trophic levels.
They found that MNPs are widely present in terrestrial ecosystems. MNPs bioaccumulate across plants and the associated AG-BG biota, causing ecotoxicological effects at multiple trophic levels. Once absorbed by plants, they interact with herbivores, pollinators, and mycorrhiza. MNPs transfer across trophic levels through multiple potential pathways, and may affect biodiversity patterns, ecosystem processes, and ecosystem multifunctionality.
Researchers then proposed key trophic and non-trophic MNPs transfer pathway within and between the AG-BG food webs, including leaves-herbivores, flowers-pollinators, prey-predators, roots-arbuscular mycorrhiza fungi, roots-herbivores, leaf litter-decomposers, AG litter-BG decomposers, BG prey-AG predators, BG larvae-AG adults.
Besides, they suggested that studies on terrestrial ecosystems are urgently needed to fully assess the ecological impacts of MNPs and to develop strategies for mitigating their effects on plants and their interconnected food webs.
