The influence of high-fluorine groundwater on surface soil fluorine levels and their FTIR characteristics

In order to detect the influence of fluorine-enriched water on surface soil (< 20 cm) fluoride levels, the groundwater and surface soil samples in Buzhuang Town, a typical drinking water fluorosis area, were sampled for the units of villages. The fluoride levels in groundwater and surface soils, and the soil FTIR were analyzed. The surface soil fluoride levels range from 492 to 711.7 mg/kg, which are higher than the average levels in neighboring areas (130-468 mg/kg), Shandong province, China, and the world. The fluoride levels of surface soils show positive correlations with groundwater fluorine levels, indicating that the surface soil fluoride levels were improved by drainage, irrigation, and other human activities. A parameter of I-intensity was designed to quantificationally estimate the amounts of functional groups. The surface soil fluoride levels are negatively correlated with soil Si-O-Si bonds and positively with soil organic matter. Thus, the substitution of groundwater F atom for the O atom of soil Si-O-Si bonds and the absorption of organic matter are the important dynamics of soil fluoride enrichment in irrigated area with high-fluorine groundwater. By this way, the enrichment dynamics and mechanisms of surface soil fluoride levels were revealed, and some scientific data are provided for the management and use of water and soil in high-fluorine groundwater areas.