Soil carbon cycling mediated by microplastics: Formation, mineralization, and sequestration

Microplastic pollution has emerged as one of the most pressing threats to global ecosystems, exerting adverse effects on terrestrial and marine ecosystems, biodiversity, and human health. Furthermore, microplastic contamination in terrestrial ecosystems poses a risk of destabilizing significant soil carbon stocks, which is crucial for mitigating climate change. Microplastics present in soil can directly participate in the carbon cycle or indirectly impact the physicochemical properties and microbial communities, thereby affecting the soil organic carbon process. This article elucidates the effects of microplastics on soil organic carbon pools through their impacts on the determination of soil organic carbon and their role in the formation, mineralization, and sequestration of organic carbon mediated by microplastics. The potential in-depth mechanisms were explored. Further studies are needed on the precise identification of microplastic source carbon, elucidation of the key microbial mechanisms involved in carbon processes, and examination of the carbon cycle process under the influence of multiple factors. © 2024 Chinese Academy of Sciences. All rights reserved.