摘要
在广东省河台金矿矿山采取岩石、土壤、植物样品,并对其中的稀土元素含量采用ICP-MS法测定,研究了金矿矿山岩石、土壤、植物的根、茎、叶稀土元素含量分布和迁移积聚特征。结果表明:在金矿区稀土元素在岩石、土壤、植物样品中含量均高于背景对照区。在成矿和表生地球化学过程中金矿土壤各层的稀土元素发生迁移和分异,在表土层和心土层含量高于底土层和成土母岩;矿山土壤各剖面层轻重稀土发生分异,轻稀土富集,重稀土相对贫乏,且均有不同程度的Eu亏损和Ce的负异常。蕨类植物芒萁(Dicranopteris dichotoma)表现极强的积累富集稀土元素能力。稀土元素在植株体内的分布规律不同,对于芒萁而言:叶>根>茎,而马尾松(Pinas massoniana)为:根>叶>茎。金矿区植物稀土元素地球化学和生物地球化学异常反映出所在金矿特殊成矿地质背景以及生境的地球化学特点。稀土元素的生物吸收系数和生物转移系数表征出植物对稀土元素的吸收富集能力以及在各个器官的迁移状况,金矿区各植物体形成对金矿环境不同的适应机制和各自独特的稀土元素生物地球化学特征。
Rocks, soils and plants in the Hetai goldfield in Guangdong province were collected for analysis of rare earth elements （REEs） by inductively coupled plasma-mass spectrometry （ICP-MS）. The distribution patterns and transportation characteristics of REEs in rocks, soils and plants （root, stem and leaf） were studied. The results show that the abundances of REEs in rocks, soils and plants in the goldfield region are much higher than those in the surrounding areas. REEs in soil profiles have been transported and accumulated during the mineral formation and supergenic geochemistry process. In a soil profile of the goldfield, REE concentrations are higher in A and B horizons than those in C horizon and parent rock. Differentiations between light REEs and heavy REEs occur revealing that heavy REEs are relatively less available,and also displaying some extent of negative Eu and Ce anomaly in the soils. A fern named Dicranopteris dichotoma shows a strong accumulation capacity for REEs. The distribution of REEs among main organs of plants differs considerably. In Dicranopteris dichotoma and Pinus massoniana total REES concentrations decrease in the order： leaf 〉 root 〉 stem, root 〉 leaf 〉stem, respectively. The strong REEs geochemical and biogeochemical anomalies of plants in the goldfield are respond to the geological setting of ore-forming processes and the geochemical characteristics of their habitats. The parameters of the biological absorption coefficients （BAC） and the biological transfer coefficients （BTC） indicate the differences of rare earth elements absorbency in plants and the transportation in the different plant organs. Plants of different genera growing in the goldfield have been forming different tolerant mechanisms responsible to gold mineralization and displaying their individual REEs biogeochemical characteristics .
出处
《生态环境》
CSCD
北大核心
2008年第1期350-356,共7页
Ecology and Environmnet
基金
中科院创新项目(KZCX3-SW-152)
国家基金重点项目(40331009
40672121)
广东省自然科学基金项目(06025464
04201163)
关键词
稀土元素
土壤
植物
河台金矿
分布
迁移
rare earth elements
soil
plant
distribution
transportation
