Microplastics could be a threat to plants in terrestrial systems directly or indirectly

• Published in: Environmental pollution (1987) Vol. 267; p. 115653
• Main Authors: Khalid, Noreen, Aqeel, Muhammad, Noman, Ali
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2020
• Subjects: Ecosystem; Emerging pollutant; Microplastic uptake; Microplastics; Phytotoxicity; Plastics; Soil; Soil Pollutants - analysis; Sorbed chemicals; Microplastic uptake; Phytotoxicity; Sorbed chemicals; Emerging pollutant
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2020.115653

Microplastics (MPs) are an emerging threat to ecosystem functioning and biota. The major sources of MPs are terrestrial and agricultural lands. But their fate, concentration in the terrestrial environment, and effects on soil and biota are poorly understood. There is a growing body of concern about the adverse effects of MPs on soil-dwelling organisms such as microbes in mycorrhizae and earthworms that mediate essential ecosystem services. Environmental concentrations and effects of MPs are considered to increase with increasing trend of its global production. MPs in the soil could directly impact plants through blocking the seed pore, limiting the uptake of water and nutrient through roots, aggregation, and accumulation in the root, shoot, and leaves. However, MPs can also indirectly impact plants by affecting soil physicochemical characteristics, soil-dwelling microbes, and fauna. An affected soil could impact plant community structure and perhaps primary production. In this article, we have assessed the potential direct and indirect impacts of MPs on plants. We have discussed both the positive and negative impacts of MPs on plants in terrestrial systems based on currently available limited literature on this topic and our hypothetical understandings. We have summarized the most current progress in this regard highlighting the future directions on microplastic research in terrestrial systems. [Display omitted] •Microplastics alter the physicochemical properties of the soil.•Altered soil structure could impact plant community composition.•Microplastics could cause toxicity in plants directly through uptake via roots.•Microplastics could impact nutrient cycling by altering the C: N ratio of the soil.•The thermal properties of microplastics could create a microclimate in the root zone in the soil. Microplastics could impact plants directly through uptake from the soil or indirectly by modifying soil structure or growth patterns of soil-dwelling organisms.