泉州湾洛阳江河口潮滩表层沉积物中重金属赋存形态分析

Speciation of heavy metals in the tidal-flat surface sediment from Luoyang River estuary of Quanzhou Bay

对比3种重金属形态提取方法,其中稀HCl法提取率比EDTA法高,改进的BCR四步提取法提取率最高.用改进的BCR法分析泉州湾洛阳江河口潮间带沉积物中重金属的4种形态(弱酸溶态、可还原态、可氧化态和残渣态)的含量.结果表明,大部分金属元素(V、Cr、Co、Ni、Zn、Fe和Cd)主要以残渣态存在,Mn主要以弱酸溶态存在,Pb和Cu则以可还原态存在.各形态与其总量间的相关性分析结果表明,Fe受人类活动的影响相对较小,而Cr、Co、Ni、Pb、Cd和Cu的前三态与其总量之间呈现极显著的正相关,说明它们主要污染源来自人类活动.

By comparing the three extraction methods of the forms of heavy metals,the extraction rate of dilute HCl method was higher than the EDTA method,and the improved BCR four-step extraction method had the highest rate.The contents of the four forms of heavy metals（acid-soluble,reducible,oxidizable and residual） in the tidal-flat surface sediment from Luoyang River estuary of Quanzhou Bay were analyzed by modified BCR procedure.The results show that most of the elements（V,Cr,Co,Ni,Zn,Fe and Cd） present comparatively higher percentages in the residual fraction.Mn presents comparatively higher percentages in the acid extractable fraction,while Pb and Cu are relatively higher in the reductive fraction.By analyzing the correlation between the forms and the total contents of these elements,human activities have relatively little effect on the content of Fe,while the contents of the first three forms of Cr,Co,Ni,Pb,Cd and Cu show significantly positive correlation with the total contents.This suggests that the main source of pollution is from human activities.