Zhang Hanyue, Yang Xiaomei, Wang Kai, Cui Jixiao, Ritsema Coen J, Yan Changrong, Liu Xuejun, Geissen Violette
State Key Laboratory of Nutrient Use and Management, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions of Ministry of Education, National Observation and Research Station of Agriculture Green Development (Quzhou, Hebei), China Agricultural University, Beijing, 100193, China; Soil Physics and Land Management Group, Wageningen University & Research, 6700 AA, Wageningen, the Netherlands.
Soil Physics and Land Management Group, Wageningen University & Research, 6700 AA, Wageningen, the Netherlands; College of Resources and Environmental Sciences, Northwest A&F University, 712100, Yangling, China.
Environ Pollut. 2025 Jan 1;364(Pt 1):125312. doi: 10.1016/j.envpol.2024.125312. Epub 2024 Nov 14.
The macroplastics (MaPs) and microplastics (MiPs) polluting agricultural soils raise great concerns. Unfortunately, scientists know little about the occurrence of MaPs/MiPs in soil among different farming systems. In this study, we analyzed MaPs/MiPs in soils (0-30 cm) collected from six different farming systems (wheat-maize rotations, cotton, vegetables, permanent orchards, greenhouses with and without mulching) in Quzhou county, the North China Plain, by using fluorescence microscope and micro-Fourier transform infrared spectroscopy. The results showed that the abundance of MaPs and MiPs ranged from 0.2 to 46.8 kg ha, and 4.1 × 10-3.7 × 10 items kg, respectively. The prominent colors of the MaPs were white and black. The predominant shape, size and chemical composition of soil MiPs were fragments (45-62%), <1 mm (98-99%), and polyethylene (38-43%), respectively. MaPs were mainly detected in the 0-10 cm soil layer. MiP abundance in the 0-10 cm soil layer was significantly higher than that in the 20-30 cm soil layers among different farming systems, except for the fields with wheat-maize rotations and permanent orchards (p < 0.05). Overall, cotton fields showed the highest MaP and MiP abundance, followed by vegetable fields and orchards. Redundancy analysis revealed that tillage practices and plastic film management greatly influence the size distribution of MiPs. A strong negative correlation between large-sized plastic fractions (0.2-1 mm) and tillage frequency was tested while the years of application of plastic films and the abundance of plastic residues showed a strong positive correlation with small-sized plastic fractions (<0.2 mm). Our findings conclude that agricultural mulch films are an important source of MaPs and MiPs in agricultural soil and distributions are strongly influenced by agricultural management practices and farming systems. Further studies should take farming systems and farming practices into account, thereby exploring the potential mechanisms of plastic fragmentation and granularization in agricultural soil.
