广东省典型花岗岩成土剖面元素垂向分布特征

Vertical distribution of some elements in typical weathering-soil profiles of granite in Guangdong Province

对广东省南部花岗岩广泛发育地区的两个花岗岩风化剖面进行部分主量元素和重金属元素含量变化的研究表明：研究区成土过程是Na、Mg、K、Ca持续风化淋失的过程,且风化程度较高,土壤剖面中重金属元素与主量元素含量的变化趋势一致。研究区两土壤剖面的淋溶作用较强,淋溶层深达200 cm,淀积层深度为100-300 cm。在淀积层内,随着Ca、K、Na、Mg等主量元素的新生矿物沉淀,As、Cd、Pb、Zn、Ni等元素也相对富集,是广东地区深层土壤As、Pb等元素含量高于表层土壤的可能成因之一。

Two granite weathering profiles developed paper. The concentrations of some major and heavy in the south of Guangdong Province were studied in this metal elements were determined by the ~tuthots. It can be concluded that the soil-forming process of the study area is a continual process of losing Na, Mg, K and Ca,the soil has been highly weathered, and the variation trend of heavy metal concentrations in two profiles is consistent with that of the major elements. It is also held that the eluviation of the two studied soil profiles is strong , the eluvial horizon has reached up to 200cm and the illuvial horizon is between 100 and 300cm in depth in the two soil profiles. In the illuvial horizon, with the precipitation of new minerals of the major elements （Ca, K, Na, Mg etc.）, the heavy metal elements （such as As, Cd, Pb, Zn and Ni ）are also relatively concentrated. These characteristics are of great significance in studying the cause of the phenomenon that the concentrations of As, Pb in deep soil are higher than those in top soil in Guangdong.