长江三角洲地区土壤重金属生物有效性的研究--以江苏昆山市为例  

BIOAVAILABILITY OF SOIL HEAVY METALS IN THE YANGTZE RIVER DELTA——A CASE STUDY OF KUNSHAN CITY IN JIANGSU PROVINCE

作　　者：钟晓兰[1] 周生路[2] 李江涛[2] 赵其国[3] 廖启林[4] 

机构地区：[1]华南农业大学信息学院,广州510642 [2]南京大学地理与海洋科学学院,南京210093 [3]中国科学院南京土壤研究所,南京210008 [4]江苏省地质调查研究院,南京210018

出　　处：《土壤学报》2008年第2期240-248,共9页Acta Pedologica Sinica

基　　金：国家重点基础研究发展规划项目(2002CB410810);国土资源部中国地质调查局与江苏省人民政府合作项目“江苏省国土生态地球化学调查”项目(20031230008)资助

摘　　要：土壤重金属的生物有效性是指土壤重金属在生物体内吸收、积累或毒性程度。以昆山市为典型区,对长江三角洲地区土壤重金属的生物有效性进行研究。结果表明,有效态Cd含量较高,生物有效性达63.8%。不同功能区重金属的生物有效性差异较大,Cd、Cu、Ni、Pb、Co以冶金电镀区最高,Cr以化工区最高,Zn以菜地区最高。不同土壤类型中Cd、Cr、Cu、Pb、Zn的生物有效性均表现为乌栅土>青泥土>黄泥土。不同母质发育的土壤上重金属生物有效性则表现为江海沉积物最高,湖相沉积物最低,且成土母质对土壤重金属的生物有效性的影响程度要大于土壤类型。随着剖面层次的下降,重金属有效态含量和生物有效性逐渐减小。植物中的重金属含量与土壤中相应的重金属的生物有效态含量显著正相关。Zn和Cd的富集系数最高,潜在风险最大。综合分析各重金属元素在土壤中的总量、生物有效性及植物中的含量,发现重金属Cd的污染最大,它将严重威胁农产品安全和地下水质量。Bioavailability of soil heavy metals refers to the degree of absorption and accumulation of soil heavy metals by organisms and toxicity to organisms. Kunshan City, typical of the Yangtze River Delta, was chosen as case for study on hioavallability of soil heavy metals. A total of 126 soil samples were collected and analyzed. Results show that available Cd ranked first in concentration, and its bioavailability reached up to 63.75 %. Significant differences were observed in bioavailability of heavy metals between different function zones, Cd, Cu, Ni, Ph and Co were the highest in the smelting and plating industry zone, Cr in the chemical industry zone and Zn in the vegetable production zone. Differences in bioavailability of Cd, Cr, Cu, Ph and Zn were also found between soil types, which were in a decreasing order of Wushan soil 〉 Qingni Soil 〉 Huangni Soil, as well as between soils of different parent materials which were lined in an order of fluvial and marine sediment 〉 lacustrine sediment. It was also found that the effect of soil forming parent materials was greater than that of soil type on the hioavailability, and that the hioavallability and contents of available heavy metals declined with the depth in soil profile. Marked positive correlation existed between concentrations of heavy metals in rapeseed and concentrations of hioavailahle heavy metals in the soil. Zn and Cd showed the highest enrichment coefficient, posing the highest potential risk. Analysis of total concentrations ＆ hioavailability of soil heavy metals and their total concentration in plant revealed that Cd was the dominant pollutant that threatens safety of agricultural production and groundwater.

关 键 词：长江三角洲 土壤重金属 生物有效性 功能区 植物 

分 类 号：X53[环境科学与工程—环境工程]