DETERMINATION OF THE CONTENTS AND DISTRIBUTION CHARACTERISTICS OF REEIN NATURAL PLANTS BY NAA

The concentration of 8 REEs (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in 17 species of plants and their host soil, which were collected front a ra re earth ore area located in the south of China, have been determined by INAA. The chondritic normalized REE patterns for different parts of plants (e.g., leaf, stem and root) and their host soils were studied. The results showed that the concentration levels of REE for most plan ts in the sampling area were elevated. particularly, the leaves of the fern (Dicranopteris dichotoma) contain extremely high concentration o f the total REE (675-3358 mu g/g). Generally, these REE distribution p atterns in every part of plants were very similar and reflected the ch aracteristics of their host soils. However, the chondritic normalized REE patterns in some plants relative to the host soil revealed obvious fractionation, such as the depletion of the heavy REE (for fern, Citr us reticulata and Brassia campestris), the heavy REE enrichment (for C amellia sinensis, Camellia oleifera and Ziziphus) and the Ce positive anomaly (for Gardenia jasminoides).