Oxidative removal of fluorescent components from soil DOM and its effect on heavy metals around abandoned mining areas

In this study, the oxidation stability of SOM and soil dissolved organic matter (DOM) for four soils around the mining area in Western  China, including grassland (GR), forest land (FR), farmland soil (FA), and mining area soil (MA), was investigated. The oxidation effect of fluorescent DOM (FDOM) was determined by using synchronous fluorescence spectroscopy (SFS). The results showed that the oxidation stability of SOM for four so ils follows the order: MA >  GR >  FR >  FA. Protein-like fluorescence (A2) is dominant in soil DOM, more than 96% of which were more easily degraded. As the wavelength increases, FDOM components become more difficult to oxidize. Second derivative, two-dimensional correlation spectroscopy (2D-COS) and 1/n power transformation can identi fy more FDOM components, protein-like materials can be preferential removal by the oxidation process, followed by humic-like substances. The oxidation process increased the release of Cr, Cu, Zn, Pb and Fe in FA soil. Therefore, the oxidation stability of SOM and FDOM can affect the immobilization a nd release of HMs, and this work provides scientific guidance for remediation of soil HMs around abandoned mining areas.
Source: Environmental Geochemistry and Health - Category: Environmental Health Source Type: research