海南岛西部地区砖红壤中稀土元素含量的空间分异特征

SPATIAL DISTRIBUTION OF REE ELEMENTS CONTENTS IN LATOSOL IN THE WESTERN PART OF THE HAINAN ISLAND

砖红壤是海南岛西部地区占地面积大、发育典型的地带性土壤,对区内不同砖红壤剖面稀土元素的组成特征及稀土元素含量的纵向变化规律进行研究发现,成土母质决定着土壤中稀土元素的最初含量,同一土壤剖面上下层土壤之间的稀土元素具有一定的继承性。砖红壤在形成发育过程中发生了轻稀土元素富集,且由深部至浅部,稀土元素总量逐步减少,而Ce也呈现出由负异常向正异常演化之趋势,土壤的淋溶作用是导致稀土元素发生纵向分异的主要原因。

Soil samples were collected from different latosol profiles in the western Hainan Province, and according to the contents of REE elements of these samples, compositions and laws of their spatial variation of the REE elements in latosol profiles were studied. Results showed that soil forming parent materials determine contents of primary REEs of the soils, and the LREEs accumulated during the formation and development of the latosol. The study also indicated that the total REEs increased with the depth of the soil profiles, but Ce turned from positive anomaly to negative anomaly, suggesting that leaching may be the main reason for variation of the vertical distribution of the REEs in the soils.