Development and environmental implication of pedotransfer functions of Cd desorption rate coefficients in historically polluted soils. (February 2020)

• Record Type: Journal Article
• Authors: Lin, Zhongbing; Zou, Xingying; Zhang, Renduo; Nguyen, Christophe; Huang, Jiesheng; Wang, Kang; Wu, Jingwei; Huang, Shuang
• Is Part Of: Environmental pollution. Volume 257(2020)
• Publication Date: 2020-02
• Subjects: Cadmium -- Desorption rate coefficient -- Pedotransfer function -- Historical pollution; 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.2019.113602
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The desorption rate is an important factor determining cadmium (Cd) ecotoxicity and pollution remediation in soils. The pedotransfer functions (PTFs) of desorption rate coefficients of fresh Cd in soils have been developed in literature. We hypothesized that the aging of Cd pollution would alter Cd desorption process. Taking historically polluted soils as the object, this study aimed at testing the hypothesis and developing new PTFs of desorption rate coefficients for historical Cd. 15 d batch extraction experiments and 13 kinetic models were employed to define Cd desorption rate coefficients in 27 historically polluted soil samples. Compared with fresh Cd, the desorption rate coefficients of historical Cd were lower, and the break time of biphasic desorption processes was retarded to 3 d (4320 min). Different with the usual models for fresh Cd desorption (e.g. parabolic diffusion and two constant rate models), the best models to mimic the historical Cd desorption processes were the pseudo first order, logarithmic, Elovich, and simple Elovich models. The rate-limiting step controlling Cd desorption was changed from the intraparticle diffusion to the interface reaction with aging of pollution. New PTFs of desorption rate coefficients of historical Cd were established ( R 2 ≥ 0.71). Cd desorption rate coefficients increased with organic matter and clay contents, but decreased with oxalate extractable Fe content, solution pH, cation exchange capacity, and silt content. The key soil properties influencing desorption rate coefficients were not altered by the aging of pollution. The developed PTFs could guide us to adjusting the ecotoxicity and pollution remediation of Cd in historically polluted field soils. Graphical abstract: Image 1 Highlights: Historical Cd in soils were extracted and desorption processes were modelled. Pollution aging retarded break time of biphasic desorption process to 3 d. Interface reaction was the rate-limiting step in desorption of historical Cd. Pedotransfer functions of desorption rates of historical Cd were developed. Abstract : Interface reaction became the rate-limiting step in Cd desorption with aging of pollution. New pedotransfer functions of desorption rate coefficients of historical Cd were established.