环境条件对上海蕴藻浜水体沉积物Ni释放影响的研究

Effect of environmental conditions on the Ni release in the Yunzaobang River sediment

通过改变环境条件(温度、pH、溶解氧),并采用Tessier五步连续提取法,研究了温度、pH和溶解氧对蕴藻浜沉积物中Ni的释放的影响,并对不同条件下的沉积物释放前后Ni的形态进行了对比分析.结果表明:随着温度的升高,沉积物对Ni的释放通量升高,可交换态、铁锰氧化物结合态以及有机物结合态在沉积物中所占百分比均上升;随着pH的增加,沉积物对Ni的释放通量下降,可交换态、碳酸盐结合态、铁锰氧化物结合态以及有机结合态所占百分比均有不同程度的增加;而溶解氧高的水体比溶解氧较低的水体更不容易释放Ni.

The effect of environmental conditions on the Ni release in the Yunzaobang River sediment was studied with Tessier continuous extraction method under different temperature of water body,pH,and concentration of dissolved oxygen.The speciation of Ni in the release process was also analyzed.The results showed that with the temperature increasing,the Ni release in the sediment increased.With the rising of pH,the Ni release decreased.The higher concentration of dissolved oxygen does little favor to the Ni release. With the change of water conditions,the five speciation of Ni,exchangeable,carbonate bound,Fe-Mn oxide,organic,and residual forms in the sediment,were also changed to some degree.