The occurrence of microplastic in Mu Us Sand Land soils in northwest China: Different soil types, vegetation cover and restoration years

Microplastic (MP) pollution in terrestrial ecosystems has aroused great concern. However, little is known regarding the distribution of MPs in Sand Land soils and their associated destinies. We investigated the MPs pollution in different areas, different vegetation cover and restoration years in Mu Us Sand Land soils. The results clearly showed that the soils of Mu Us Sand Land contain a relatively higher MPs abundance. The significant differences of MPs abundance were demonstrated among soil from sand, grassland and woodland, which the total MP abundance of sand soil was higher than that of grassland and woodland. The distribution of MP size in the woodland area primarily from 0 to 0.50 mm, which is significantly higher than that other areas. In addition, the highest concentration of MP collected was found at Salix tree (ST), followed by Poplar tree (PT) and Chinese pine (CP), while the lowest concentration was at Pinus sylvestris (PSs) and Jujube tree (JT). It is worth noting that the abundance of MPs decreases with restoration years increased, whether it is PT or PSs. We speculate that the tree disturbance in the sampling area might affect the distribution of microplastics and then be conducive to plastic fragmentation.

Automated summary

The investigation revealed a relatively high abundance of microplastics in Mu Us Sand Land soils, with the woodland area showing a higher concentration of microplastics in the size range of 0 to 0.50 mm. Different tree species exhibited variations in microplastic accumulation, and the abundance of microplastics decreased with increasing restoration years.