第11卷第4期 2016年12月
doi:10.3969/j.issn.1007-1903.2016.04.011
域市地翼 URBANGEOLOG)
Vo1.11 No.4 December，2016
土壤元素异常成因研究及生态风险评价
胡省英，黄丹，邓凯文，杨力，李迪
（北京市地质勘察技术院，北京102218）
摘要：山区岩石与水系沉积物，对山前平原土壤物质组成具有控制作用。土壕地球化学调查，查明北京某地区土壤存在着大面积同心图状的辐、铜、错等多金属元素异常。研究表明，西北侧山区分布着种类繁多的岩浆岩、变质与沉积岩，但与山前土填具有高度正相关的元素组含特征的主要是燕山期中酸性岩蒙杂岩体，而且杂岩体周动及其下游的 BY沟水系沉积物中的多金属元素也呈现出明显的高背景含量特征。同时，错同位素组成亦指示山前平原土壤铅与山区岩浆岩铅、沉积岩铝具有一致的物质来源，从而证实山前土境多金属元景异常主要来源于山区岩浆杂岩体。由于山
关键词：元素并常；土壤；岩石；水系沉积物；籍同住素；生态风险
中图分类号：S153；S662.1
文献标识码：A
文章编号：1007-1903（2016）04-0059-07
TheElementAbnormalGeneticResearchofsoil andItsEcologicalRisk
Assessment
HUShengying,HUANGDan,DENGKaiwen,YANGLi,LIDi
(Beijing Institute of Geo-exploration and Technology; Beijing /02218)
Abstract: Soil materials in piedmont plain are controlled by rocks and stream sediments in mountain areas. Soil geochemical survey shows that there are wide ranges of concentric cirele of multi metal element abnormality such as Cd, Cu, Pb and so on in a region of Beijing, where the magmatic rocks, sedimentary rocks and metamorphic rocks are wide distributed. Of them, the Yanshanian intermediate acidic magmatic complexes' elements are high positively correlated with piedmont plain soil. There are high content characteristics of multi-elements obviously in stream sediments of the magmatic complexes and its downstream sediments of Baiyang valley. Lead isotope composition supports that lead in soil has consistent source of material with lead in mountain magmatic and sedimentary rocks. So it is proved that the multi metal element abnormalities in piedmont plain are mainly derived from magmatic complexes. Because of the alkaline soil and cultivated land crops, the ecological risk of multi-metal elements soil in piedmont plain to the growth of crops is low.
Keywords: Element abnormality; Soil; Rock; River sediment; Lead isotope; Ecological risk
0前言
山前平原土壤元素的空间分布与广大平原区明
显不同，更多地反映出山区岩石与水系沉积物的地球化学特征，亦即山前平原土壤与水系沉积物、岩石之间存在着密切的因果关系。据近十几年对北京
基金课题：中心城区和昌平一马池口地区土壤重金属赋存形态研究（京地[201436号）
作者简介：胡省莫（1962-），女，高工，主要从事土壤，若石地球化学研究工作。E-mail；hushengringbj@163.com