珠江口沉积物中痕量金属富集研究

由相关系数和主成份分析 ,选择铁和铝作为沉积物中痕量金属浓度的均一化元素 .沉积层面中金属浓度超过线性基线模型的 95 %预测上限被视为富集 .结果表明 ,珠江口沉积物中金属富集主要出现在西部浅水区和东侧航道 ,明显受河口水动力条件和沿岸人类活动的影响 .富集层面中痕量金属大部分结合在相对稳定的地球化学相上 ,生物可给性较低 .痕量金属富集的空间分布表明铜和锌主要来自点源排放 ,铅则表现出非点源特征 .

Study on trace metal enrichment in sediments from Pearl River estuary

Based on correlation coefficients and principal component analysis, Fe and Al were selected as the concentration normalizer for the different trace metals. Sediment sections with metal levels exceeding the upper 95% prediction interval of the linear baseline model were regarded as enrichment layers. Metal accumulation mainly occurred in the western shallow water areas and the eastern channel, which indicated that the influence was from hydraulic conditions and riparian anthropogenic activities. Since the enriched metals were mainly bound to the relatively stable geochemical fractions, the bioavailability was generally low. The spatial distribution of cumulative metals suggested that Zn and Cu mainly originated from point sources, while Pb prabably came from non-point sources.