Effect of Drying–Rewetting cycles on the metal adsorption and tolerance of natural biofilms. (1st February 2023)

• Record Type: Journal Article
• Authors: Xie, Shanshan; Wang, Wenwen; Li, Nihong; Wen, Chen; Zhu, Shijun; Luo, Xia
• Is Part Of: Journal of environmental management. Volume 327(2023)
• Publication Date: 2023-02-01
• Subjects: Drying-rewetting cycles -- Biofilm -- Heavy metal -- Adsorption -- Tolerance; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2022.116922
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Drying–rewetting (D-RW) cycles can induce changes in biofilms by forcing the microbial community to tolerate and adapt to environmental pressure. Existing studies have mostly focused on the impact of D-RW cycles on the microbial community structure, and little attention has been paid to how D-RW cycles may change the biofilm tolerance and adsorption of heavy metals. We experimentally evaluated the effect of repeated D-RW cycles on the Cd 2+ and Pb 2+ adsorption and tolerance of biofilms. The equilibrium adsorption capacity of the biofilm decreased as the number of D-RW cycles was increased, which was attributed to a change in affinity between the biofilm and metal ions. For a binary metal system, the D-RW cycles affected the competitive adsorption of Cd 2+ and Pb 2+ by the biofilm. A synergistic effect was observed with one and three D-RW cycles, while an antagonistic effect was observed for the control film and five D-RW cycles. The tolerance of the biofilm to Cd 2+ and Pb 2+ increased with the number of D-RW cycles. The stress from the D-RW cycles may have increased the relative abundance of drought-tolerant bacteria, which altered the biofilm functions and thus indirectly affected the heavy metal adsorption capacity. Graphical abstract: Image 1 Highlights: The drying-rewetting cycles affected competitive adsorption of Cd 2+ and Pb 2+ by biofilm. Drying-rewetting cycles forced the microbial community to adapt environmental pressure. The stress from the drying-rewetting cycles indirectly affected metal adsorption capacity.