Effect of particulate organic matter fractions on the distribution of heavy metals with aided phytostabilization at a zinc smelting waste slag site. (October 2019)

• Record Type: Journal Article
• Authors: Luo, Youfa; Wu, Yonggui; Shu, Jie; Wu, Zhixue
• Is Part Of: Environmental pollution. Volume 253(2019)
• Page Start: 330
• Page End: 341
• Publication Date: 2019-10
• Subjects: Particulate organic matter -- Heavy metals -- Interaction -- Zn smelting waste slag -- Aided phytostabilization; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2019.07.015
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Particulate organic matter (POM) significantly affects the distribution of heavy metals in contaminated soil. However, the effect of POM on the fate of heavy metals during in situ- aided phytostabilization of waste slag is unclear. The objective of this study was to investigate the distributions of heavy metals such as Cu, Pb, Zn, and Cd in the POM fractions at a zinc smelting waste slag site under in situ- aided phytostabilization after five years. The results showed that the litters and residues of four plants― Arundo donax, Broussonetia papyrifera, Cryptomeria fortunei, and Robinia pseudoacacia ―decomposed to form different POM size fractions. The percentage of the 0.05–0.25 mm POM size fraction was the highest, followed by the >1 mm and 0.5–1 mm POM size fractions, and that of the 0.25–0.5 mm POM size fraction was the lowest. The masses of POM derived from the four plants were in the following order: C. fortunei > B. papyrifera > A. donax > R. pseudoacacia . The contents, enrichment coefficients, and mass loads of heavy metals such as Cu, Pb, Zn, and Cd in the POM increased with decreasing POM size, and those in the 0.05–0.25 mm POM size fraction were the highest. The mass load of heavy metals in the POM occurred in the following order: Cu > Cd > Zn > Pb. The surfaces of the POM with coarser and smaller size fractions were smoother and rougher, respectively, and the smaller POM size fractions had larger specific surface areas. The main functional groups in the different POM size fractions were –COOH, –OH, CO, CC, C–H, Si–O, and –CH3 . The POM fractions played a significant role in determining the distribution of heavy metals in the revegetated waste slag. These findings have important implications for aided phytostabilization, which significantly influences the fate and speciation of heavy metals at the phytoremediation site. Graphical abstract: Image 10791 Highlights: POM fractions on heavy metal fate at a phytoremediation site was firstly studied. Heavy metal enrichment in the POM fractions increased with decreasing POM size. The 0.05–0.25 mm POM fractions had the highest adsorption capacity for metals. The kinds of functional groups in the different POM size fractions were similar. Abstract : Heavy metal distributions in different particulate organic matter size fractions significantly influenced the fate and speciation of heavy metals at a phytoremediation site.