Peat and bentonite amendments assisted soilless revegetation of oligotrophic and heavy metal contaminated nonferrous metallic tailing. (January 2022)

• Record Type: Journal Article
• Authors: Liu, Chenjing; Lin, Hai; He, Peidong; Li, Xiaoyin; Geng, Yuan; Tuerhong, Aminaimu; Dong, Yingbo
• Is Part Of: Chemosphere. Volume 287:Part 1(2022)
• Publication Date: 2022-01
• Subjects: Nutrient content -- Heavy metal bioavailability -- Rhizosphere microbial community -- Revegetation regulation -- Microecology; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.132101
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Soilless revegetation is a promising method for ecological restoration of nonferrous metallic tailings because of its low-cost and eco-friendliness. However, revegetation is difficult to construct in the tailings due to the high heavy metal concentration, poor water retention capacity and low fertility. In this study, soilless revegetation was successfully carried out by using peat and bentonite amendments. The results showed that amendment addition significantly increased the F.elata seed germination percentage, plant length and fresh biomass by 14.9%–24.3%, 48.9%–90.4% and 51.9%–88.1%, respectively. Such improvements probably referred to the variation of rhizosphere tailing microecological characteristics. Amendment addition dramatically improved tailing available NPK by 39.76–102.13%, 2.69–40.81% and 2.42–20.02%, respectively, and reduced pH from alkaline to relative neutral. Besides, heavy metal bioavailability was significantly decreased that the acid soluble fraction decreased by 1.7%–11.5%, resulting in the reduction of heavy metal concentration in F.elata plant. Amendments also increased the rhizosphere tailing microbial species richness and the relative abundance of ecologically beneficial genera including Arthrobacter, Altererythrobacter and Bacillus . This study not only provided a green and efficient method for remediation of oligotrophic and high heavy metal contaminated nonferrous metallic tailing, but also demonstrated relevant mechanisms of amendment on promoting soilless revegetation. Graphical abstract: Image 1 Highlights: Amendment addition significantly improved tailing soilless revegetation efficiency. Rhizosphere tailing nutrient content was increased in the presence of amendments. Heavy metal bioavailability in rhizosphere was decreased by amendment application. Microbial species richness and ecologically beneficial rhizobacteria were improved. Rhizosphere micro-ecology showed closely correlation with soilless revegetation.