Assessment of heavy metal enrichment factors and the degree of contamination in marine sediments from Tamaki Estuary, Auckland, New Zealand
Assessment of heavy metal enrichment factors and the degree of contamination in marine sediments from Tamaki Estuary, Auckland, New Zealand
复制标题
DOI：
10.1007/s10661-007-9678-2
复制
发表时间：
2008-01-01
影响因子：
3
通讯作者：
Parker, R. J.
中科院分区：
文献类型：
--
作者：
Abrahim, G. M. S.;Parker, R. J.
八个沉积物岩心回收玉木河口进行了分析，铜，铅，锌，镉使用向下取芯子样品。结果表明，在最上层0-10厘米的重金属浓度最高的一个显着的向上富集。评估海洋沉积物中的重金属污染需要了解人类活动前的金属浓度，以此作为比较测量值的参考。原始值的岩心沉积物确定从平坦的“基线”金属趋势明显较低的核心样品。详细审查了计算金属富集和污染因子的各种方法，并提出了计算污染程度的程序的修改和更强大的版本。修订后的程序允许纳入一系列灵活的污染物，包括各种有机物，污染程度以平均比率而不是绝对总和表示。归一化富集因子和修改后的污染程度的比较数据表明，玉木河口沉积物遭受了显着的系统性重金属污染的流域城市化。与基线值相比，最上层的沉积物显示，八个岩心和四种分析金属的平均富集程度为四倍。
Eight sediment cores recovered from Tamaki Estuary were analysed for Cu, Pb, Zn, and Cd using downward cored sub-samples. The results indicate a significant upward enrichment in heavy metals with the highest concentrations found in the uppermost 0-10 cm layer. Assessment of heavy metal pollution in marine sediments requires knowledge of pre-anthropogenic metal concentrations to act as a reference against which measured values can be compared. Pristine values for the cored sediments were determined from flat "base-line" metal trends evident in lower core samples. Various methods for calculating metal enrichment and contamination factors are reviewed in detail and a modified and more robust version of the procedure for calculating the degree of contamination is proposed. The revised procedure allows the incorporation of a flexible range of pollutants, including various organic species, and the degree of contamination is expressed as an average ratio rather than an absolute summation number. Comparative data for normalized enrichment factors and the modified degree of contamination show that Tamaki Estuary sediments have suffered significant systematic heavy metal contamination following catchment urbanization. Compared to baseline values the uppermost sediment layers show four-fold enrichment averaged across eight cores and four analysed metals.