Effect of root exudates on the release, surface property, colloidal stability, and phytotoxicity of dissolved black carbon

Ecotoxicology and Environmental Safety

Baoshan Xing¹  Yaru Han²  Zhenyu Wang²  Shiguo Gu²  Fei Lian³ 

[1] Correspondence to: School of Environment and Civil Engineering, Jiangnan University, Lihu road 1800, Wuxi 214122, China.;Institute of Environmental Processes and Pollution Control, and School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China;School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China;

关键词: Dissolved black carbon;    Root exudates;    Physicochemical property;    Colloidal stability;    Free radicals;    Phytotoxicity;   

DOI  :  

来源: DOAJ

【 摘 要 】

In this study, the release of dissolved black carbon (DBC) from bulk-BC, its surface properties, colloidal stability, and oxidative stress to rice seedlings in the presence and absence of rice root exudates were compared. The bulk-BCs were prepared at 550 °C and derived from wood chips and pig manure, respectively. The release of DBC from bulk-BC was significantly enhanced (20.19–23.63%) by the introduction of root exudates, where low molecular weight organic acids played a dominating role in the dissociation of DBC from carbon skeleton. The surface properties of DBC were greatly modified by root exudates including decreases in the surface area (18.13%) and mineral contents (43.90–69.57%). The O-containing groups and graphitization were also enhanced by 11.46% and 18.65%, respectively. Meanwhile, the presence of root exudates not only reduced the colloidal stability of DBC but also lowered the intensity of free radicals (19.44–22.22%) in DBC. Consequently, the oxidative stress of DBC to rice seedlings was significantly (p < 0.05) alleviated, evidenced by reduced antioxidative enzyme activities (5.67–29.25%) and soluble protein content (15.75–46.79%) in rice plants. These results indicate that the interaction between DBC and root exudates could remarkably modify the surface properties and reactivity of DBC, which has profound implications for understanding the behavior and functions of DBC in the environment.

【 授权许可】

Unknown