Fig 1.
Scanning electron micrographs of polystyrene nanoplastics.
Table 1.
Original physicochemical properties of soil.
Table 2.
Experimental treatment design.
Fig 2.
Individual and combined effects of PS-NPs and Cd stress on S. alfredii growth.
a): Fresh and Dry weights; b): Plant height and Root length.C1 and C2 respectively represented the concentration of Cd (0.6 and 4 mg·kg-1), and N1 and N2 respectively represented the concentration of PS-NPs (100 and 1000 mg·kg-1). Different letters indicate significant differences (P < 0.05).
Fig 3.
Individual and combined effects of PS-NPs and Cd on antioxidant enzyme activities and MDA content in S. alfredii.
(a): SOD: superoxide dismutase; (b): POD: peroxidase; (c): CAT: catalase; (d): MDA: malondialdehyde. PS-NPs: polystyrene nanoplastic; Cd: cadmium.C1 and C2 respectively represented the concentration of Cd (0.6 and 4 mg·kg-1), and N1 and N2 respectively represented the concentration of PS-NPs (100 and 1000 mg·kg-1). Different letters indicate significant differences in the results; the same letters indicate non-significant differences in the results (P < 0.05).
Fig 4.
Individual and combined effects of PS-NPs and Cd on Cd chelation (GSH, NPT and PCs) in S. alfredii leaves.
GSH: glutathione; NPT: nonprotein thiol; PCs: phytochelatins. PS-NPs: polystyrene nanoplastic; Cd: cadmium.C1 and C2 respectively represented the concentration of Cd (0.6 and 4 mg·kg-1), and N1 and N2 respectively represented the concentration of PS-NPs (100 and 1000 mg·kg-1). Different letters indicate significant differences in the results; the same letters indicate non-significant differences in the results (P < 0.05).
Fig 5.
Individual and combined effects of PS-NPs and Cd stress on Cd and trace element contents in S. alfredii.
(a): Cd content (mg·kg-1); (b): Zn content (mg·kg-1); (c): Cu content (mg·kg-1); (d): Mn content (mg·kg-1). PS-NPs: polystyrene nanoplastic; Cd: cadmium.C1 and C2 respectively represented the concentration of Cd (0.6 and 4 mg·kg-1), and N1 and N2 respectively represented the concentration of PS-NPs (100 and 1000 mg·kg-1). Different letters indicate significant differences in the results; the same letters indicate non-significant differences in the results (P < 0.05).
Fig 6.
Individual and combined effects of PS-NPs and Cd stress on Cd speciation contents in soil.
PS-NPs: polystyrene nanoplastic; Cd: cadmium.C1 and C2 respectively represented the concentration of Cd (0.6 and 4 mg·kg-1), and N1 and N2 respectively represented the concentration of PS-NPs (100 and 1000 mg·kg-1). Different letters indicate significant differences in the results; the same letters indicate non-significant differences in the results (P < 0.05).