Water—Soluble Rare Earth Elements in Some Soils of China
摘要
Water-soluble rare earth elements(WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer, Results showed that the conents of WSREEs decreased from upper layer to lower layer of soils in the southern part of Chian with a high rainfall and low pH but increased for soils in the northern part of China with a low rainfall and relatively higher pH. Contents of WSREEs in soils were olwer than 100μg kg^-1 in most cases ,and varied greatly with both different soils and different layers of the same profile .The highest content was 2816.3μg kg^-1 but the lowest was 17.6μg kg^-1 only.The content of individual rare earth lement(REE) in the soil solution also varied greatly with the highest one ranging from 8.4 to 1373μg kg^-1 for Ce and the lowest one from 0.05 to 4.48μg kg^-1 for Lu.The sum of WSREEs in the first soil layers ranged from 121.5 to 345.6μg kg^-1.Great variaions existed among ratios of REEs in the first soil layers ranged from 121.5 to 345.6μg kg^-1.Great variations existed among ratios of REEs extracted with water to the total REEs of soils,ranging from 0.02×10^-3 to 13.2×0^-3 .But as the upper layer was consiered,the ratio showed only a small difference, ranging from 0.79×10^-3 to 1.69×10^-3.