Land-Use Types Regulate Se:Cd Ratios of Natural Seleniferous Soil Derived from Different Parent Materials in Subtropical Hilly Areas

As natural selenium (Se)-rich soil in China is generally characterized by a high geological background of cadmium (Cd), the safe utilization such seleniferous remains challenge. The accumulating evidence shows that threshold value Se:Cd ratio determinant regulating Cd accumulation plants. However, factors modulating soil’s selenium-enriched regions are not well understood. Here, comprehensive study aimed at quantitatively analyzing effects land-use types, parent-material and properties on distribution influencing Se, Cd, ratios. According to land use 77 samples were collected Yuanzhou District, typical naturally area subtropical hilly area. results suggested that, compared with quaternary red clays (qrc), Se content soils derived from river lake sediments (rls) weathered acidic crystalline rocks (wacr) decreased 5.81%–19.75%, while quartzite (wq)-derived was increased significantly. an orchard significantly reduced paddy field. A redundancy analysis (RDA) revealed SOM, Total K, P affected changes contents. In addition, type had most significant effect ratio, regression coefficient −0.6999 analyzed binary logistic model (p < 0.05). Furthermore, pH K critical controlling ratio. indicated selenium-rich mainly regulated types. Therefore, it feasible measure regulate using agronomic practices, pH, for background.