Recent advances in the research on effects of micro/nanoplastics on carbon conversion and carbon cycle: A review

Massive production and spread application of plastics have led to the accumulation of numerous plastics in the global environment so that the proportion of carbon storage in these polymers also increases. Carbon cycle is of fundamental significance to global climate change and human survival and development. With the continuous increase of microplastics, undoubtedly, there carbons will continue to be introduced into the global carbon cycle. In this paper, the impact of microplastics on microorganisms involved in carbon transformation is reviewed. Micro/nanoplastics affect carbon conversion and carbon cycle by interfering with biological fixation of CO2, microbial structure and community, functional enzymes activity, the expression of related genes, and the change of local environment. Micro/nanoplastic abundance, concentration and size could significantly lead to difference in carbon conversion. In addition, plastic pollution can further affect the blue carbon ecosystem reduce its ability to store CO2 and marine carbon fixation capacity. Nevertheless, problematically, limited information is seriously insufficient in understanding the relevant mechanisms. Accordingly, it is required to further explore the effect of micro/nanoplastics and derived organic carbon on carbon cycle under multiple impacts. Under the influence of global change, migration and transformation of these carbon substances may cause new ecological and envi-ronmental problems. Additionally, the relationship between plastic pollution and blue carbon ecosystem and global climate change should be timely established. This work provides a better perspective for the follow-up study of the impact of micro/nanoplastics on carbon cycle.

Automated summary

Mass production and widespread use of plastics have led to the accumulation of plastics in the environment, increasing the proportion of carbon storage in these polymers. Microplastics affect carbon conversion and cycle by interfering with biological fixation of CO2, microbial structure and community, functional enzyme activity, gene expression, and local environment. Plastic pollution can also impact the blue carbon ecosystem and its ability to store CO2 and fix marine carbon. However, limited information is available to fully understand the mechanisms involved. Further research is needed to explore the effects of microplastics and derived organic carbon on the carbon cycle under multiple impacts. The relationship between plastic pollution, blue carbon ecosystem, and global climate change should also be established in a timely manner. This work provides a valuable perspective for future studies on the impact of microplastics on the carbon cycle.