A 120-day soil incubation experiment was conducted to investigate the effects of rice husk biochar on soil properties and cadmium(Cd)immobilization in polypropylene micro-/macroplastics and Cd co-contaminated soils. The results showed that biochar addition significantly improved soil pH in the co-contaminated soils compared to the control group. It also considerably increased the content of dissolved organic carbon in soils co-contaminated by 7% plastics and Cd. In addition, biochar promoted the conversion of Cd from the active form into relatively stable form in the particulate organic matter and mineral fractions, effectively reducing both the bioavailable Cd content and the proportion of DTPA-extractable Cd(DTPA-Cd)in the co-contaminated soils. Specifically, biochar reduced the bioavailable Cd content by 7.58%~19.71% and the DTPA-Cd proportion by 20.23%~30.83% in microplastics and Cd co-contaminated soils. For macroplastics and Cd co-contaminated soils, the corresponding reductions were 23.80%~28.19%and 21.63%~22.74%, respectively. Notably, the concentration of microplastics was positively correlated with the content of bioavailable Cd, while the concentration of macroplastics showed no significant effect on it. The findings demonstrated that rice husk biochar effectively alleviated the adverse effects of the plastics and Cd co-contamination through improving soil properties, mediating the migration and transformation of Cd among soil solid fractions, as well as adsorbing and immobilizing Cd.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |