Geochemistry of rare earth elements in soils under different land uses in a typical karst area, Guizhou Province, Southwest China

Understanding soil erosion processes under different land uses is important for predicting and controlling watershed soil losses, especially in karst areas. Five soil profiles and 55 soil samples were collected from soils that were under different land uses in a typical karst catchment, Southwest China. The total contents of rare earth elements (REE) are significantly lower (< 100 mg kg(-1)) than the average value of soils in China (181 mg kg(-1)). The enrichment degree of REE in heavy REE is much higher than that of light REE in all soil samples. A positive Ce anomaly (similar to 1.4) and a slightly negative Eu anomaly (similar to 0.95) were found. The enrichment and release of REE are partly controlled by pH, distribution of REE in bedrocks, contents, and adsorption ability of organic matters in weathering profiles.