[Fluorine speciation in soil and the remediation of fluorine contaminated soil]. / 土壤氟形态与氟污染土壤修复.

In China, fluoride pollution in soil is severe and poses a serious threat to human health and ecological security. However, how to control fluorine-contaminated soil has not received widespread attention. Here, we summarized fluorine speciation in soil and its main chemical reactions in water-soil system and reviewed the research progress on the remediation of fluorine-contaminated soils. Then, we proposed the focus of future research on fluorine-contaminated soil remediation. The aim of this review was providing the reference for the remediation of fluoride-contaminated soil. There are five forms of fluorine in soils, with the proportion of residual fluorine being over 90%. The reactions of fluorine in the soil solution mainly include precipitation-dissolution, complexation-dissociation, and adsorption-desorption. At present, the remediation technology of fluorine contaminated soil mainly focused on chemo-immobilization, chemical leaching, electrokinetic remediation, and phytoremediation. Clarifying the combined forms of fluorine in soil, screening functional microorga-nisms and plants, developing the combined remediation technology will be the focus of future research. Ultimately, on site fluorine-contaminated soil remediation could be implemented.

[Effects of Remedies on the Remediation of Typical Pb and Zn-contaminated soil in Huanjiang, Guangxi].

Due to the collapse of the Pb/Zn tailing dam of Huanjiang, Guangxi, the farmland along Huanjiang River are strongly acidic and heavy metal-contaminated, resulting in the loss of agricultural production. To explore some remedies and the migration of heavy metals in heavy metal contaminated-soil of Huanjiang, this study investigated the effects of different types of amendments (lime, calcium magnesium phosphate, organic fertilizer, polypropylene amide) on tested soils through soil leaching test. The results showed that T1 soil was severely acidified, reducing the pH of the soil layer to clean contact, while T2, T3, T4, T5 could significantly improve the contaminated soil pH, ranging from 2.7 to 3.2, 1.6 to 2.7 respectively. Compared with T1, in the contaminated soil at 0-20 cm, T2, T3, T4, T5 could effectively activate Pb and immobilize Zn. Compared with T1, in 20-60 cm clean soil, there was no significant differences in the effect of different treatments on DTPA-Pb and DTPA-Zn (P < 0.05). Compared with T1, T4 and T5 could provide good growing conditions for plants, which might provide technical support for future measurements such as bioremediation.