摘要
为研究典型喀斯特山地贵金属矿区耕地土壤重金属镉污染,及上附农作物的富集特征.选取遵义某Ni-Mo矿区为研究对象,采集了周边耕地土壤及农作物样品.采用ICP-MS检测其中Cd的含量,利用改进型连续提取法分步提取重金属形态,并评价土壤污染和农作物的富集水平.结果显示,研究区土壤Cd的平均含量为1.68 mg·kg-1,且在旱地和水田土壤中含量分别为1.57 mg·kg-1和2.16 mg·kg-1.残渣态是主要的存在形式,水田土壤酸溶态高于旱地.农作物中Cd的含量范围为0.022—1.276 mg·kg-1,其含量变异系数在0.19—0.73之间,属中高度变异.评价结果表明研究区耕地土壤普遍存在Cd的污染,不同耕地使用方式影响农作物对Cd积累.6种农作物对Cd的生物富集系数都小于1,其中主食类农作物的生物富集作用小于副食类;此外Cd在农作物辣椒中存在富集现象,在水稻中程度较低.
This work was trying to study the contamination of Cd in cultivated land soils and their enrichment characteristics by crops around a precious metals mining in typical karst mountainous area. An abandon Ni-Mo mining in Zunyi district was selected as research objective, and soil samples were collected from dry land and paddy field in study region. Simultaneity, crops samples were collected as well. ICP-MS was applied to test the content of Cd in samples, and speciation of heavy metals was analyzed via an improved continuous extraction method. Soil pollution level and bioconcentration degree were discussed. The results show that the average content of Cd in soils was 1.68 mg·kg-1, and the mean content in dry land and paddy field were 1.57 mg·kg-1 and 2.16 mg·kg-1, respectively. Residual form is the dominate form of Cd, and the acid-soluble fraction in paddy field was higher than that in dry land. The average content of Cd in crops were 0.022—1.276 mg·kg-1 and the coefficient of variation are between 0.19 and 0.73, it belonging to moderate to highly variable. The studied area was polluted by Cd universally, and discrepancies were observed between the accumulating characteristics of Cd in dry land and paddy field. The bioconcentration coefficient of Cd in six studied crops were less 1, and enrichment capacity of staple food crops was lower than that of non-stable food crops. Cd were tend to accumulated in pepper, and rice showed the lowest accumulating capacity among studied crops to Cd heavy metals.
作者
王兴富
黄先飞
胡继伟
吴先亮
姚世美
WANG Xingfu;HUANG Xianfei;HU Jiwei;WU Xianliang;YAO Shimei(School of Karst Science,Guizhou Normal University,Guiyang,550001,China;Guizhou Provincial Key Laboratory Information System of Mountainous Areas and Protection of Environment,Guizhou Normal University,Guiyang,550001,China)
出处
《环境化学》
CAS
CSCD
北大核心
2020年第7期1872-1882,共11页
Environmental Chemistry
基金
贵州省科学技术基金(黔科合基础[2019]1217)资助
作者简介
通讯联系人:王兴富,Tel:+8615285157623,E-mail:wang88xingfu@163.com
