黄河下游水体中重金属元素的季节变化及入海通量研究

The Seasonal Changes and Flux of Trace Elements in the Lower Reaches of Yellow River

于2008年12月～2009年11月间,在黄河下游利津进行每月1次为期12个月的样品采集工作,测定了水体中溶解态和颗粒态Cu、Pb、Cd、Cr、As、Hg的含量,并对其分布特征及影响因素进行探讨。结果表明:黄河下游溶解态Cu、Pb、Cr、Cd、As、Hg含量的变化范围分别为1.07～3.18、0.14～0.47、0.13～0.24、0.17～0.39、1.39～2.12、0.11～0.14μg/L,颗粒态Cu、Pb、Cr、Cd、As、Hg含量的变化范围分别为3.58～58.09、2.91～31.78、2.84～42.20、0.042～0.65、0.14～3.28、0.023～0.20μg/g。计算了重金属在颗粒物-水相间的分配系数。结果显示:黄河下游悬浮物吸附重金属离子的能力较强,对水体中溶解态重金属的具有一定的抑制作用。黄河下游溶解态重金属的含量与流量没有明显的相关关系;但颗粒态重金属的含量与流量和SPM存在明显的负相关关系。Cu、Pb、Cr主要以颗粒态的形式进入渤海;汇入渤海的溶解态和颗粒态Cd、As、Hg的通量则基本持平;黄河下游重金属的入海通量主要受黄河流量的控制。

Samples from the Yellow River were collected monthly over the lower reaches from December 2008 to November 2009. By using AAS and AFS, soluble and particulate trace elements were analysed. Though discussing the reasons of these phenomenon, it demonstrated that the concentrations of soluble Cu, Pb, Cr, Cd, As, Hg ranged from 1.07 to 3.18, from 0.14 to 0.47, from 0.13 to 0. 24, from 0. 17 to 0.39, from 1.39 to 2.12, from 0.11 to 0.14 μg/L, as well as the concentrations of particulate Cu, Pb, Cr, Cd, As, Hg were 3.58~58.09, 2.91~31.78, 2.84~42.20, 0. 042~0.65, 0. 14~3.28, 0. 023~ 0. 20μg/g. By calculating the Kas, it was summarized that the suspended matter in the lower reaches of Yellow River had good performance to adsorb heavy metals and had inhibiting action to dissolved heavy metals. No significantly relationship was found between soluble heavy metals and water discharge, while the particulate heavy metals showed apparently negative correlation with water discharge and SPM. The results also showed that particle state was the main existence form into the Bohai Sea for Cu, Pb and Cr, while the soluble and particulate Cr, As and Hg evenly distributed. The flux of heavy metals into the Bo- hai Sea was mainly controlled By water flow.