河台金矿矿山土壤-植物系统微量元素地球化学和生物地球化学特征

GEOCHEMICAL AND BIOGEOCHEMICAL CHARACTERISTICS OF TRACE ELEMENTS IN THE SOIL-PLANT SYSTEM IN THE HETAI GOLDFIELD,GUANGDONG PROVINCE

在广东省河台金矿矿山采取土壤、植物样品,并对其中的微量元素含量采用ICP-MS法测定,研究了金矿矿山土壤、植物的根、茎、叶微量元素地球化学和生物地球化学特征。结果表明:在成矿和表生地球化学过程中金矿土壤各层的微量元素发生迁移和分异,在表土层和心土层含量高于底土层;土壤各剖面层中Au及Au的伴生元素As、Hg、Cu、Pb明显高于背景对照区和中国土壤背景值;植物体内微量元素的含量特征受所处土壤环境影响,同时表现出每种植物独特的生物地球化学特征和对金矿环境的耐性机制;运用微量元素的生物吸收系数和生物转移系数表征植物对微量元素的吸收富集能力以及在各个器官的迁移状况。

The concentrations of trace elements in the soil-plant system taken from the Hetai goldfield in Guangdong Province were determined by the ICP-MS method and their geochemical characteristics were studied. Results showed that the trace elements in soil profiles have been transported and accumulated during the mineral formation and supergenic geochemical process. In the different layers of soils, the concentrations of trace elements in layer A and layer B are higher than in layer C. The concentra- tions of Au and Au-associated elements such As, Hg, Cu, Pb in the soil in the mineralized area are much higher than those in the surrounding regions. The distributions of trace elements in plants are influenced by soils and also have their individual biogeochemical characteristics. And different plant species display different tolerant mechanisms to the Au mineral surrounding. The biological absorption coefficients （BAC） and the biological transfer coefficients （BTC） indicate the differences in absorbency of trace elements in plants and their transportation in different plant organs.