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利用围隔式生态实验装置研究了加拿大False河口污染沉积物中重金属Pb、Zn、Cd、Cu在海水环境中的行为。实验模拟了 4种环境条件 :( 1)高生产力 ;( 2 )低生产力 ;( 3 )高悬浮物含量 ;( 4 )还原环境。结果表明 ,污染沉积物中重金属在海水环境中的行为既取决于元素自身性质 ,亦受外界环境条件制约。还原环境能抑制重金属的释放 ,有助于体系中原有的重金属清除出水柱。低生产力条件下 ,Pb、Zn表现出释放行为 ,而高生产力和高悬浮物含量条件下 ,Pb、Zn表现出先释放后迁移 ,而Cd、Cu则呈现出相反的图象。研究了实验期间 4种重金属释放与迁移的净通量 ,表明氧化条件下Cu、Zn净释放通量比Cd、Pb高 1～ 2个量级。研究表明 ,添加粘土及向还原环境倾倒均有助于减轻污染沉积物倾倒后重金属的二次污染
The behavior of heavy metals Pb, Zn, Cd and Cu in the polluted sediments in the False estuary of Canada was studied in a seawater environment by the enclosure ecological experiment device. The experiment simulated four kinds of environmental conditions: (1) high productivity; (2) low productivity; (3) high suspended solids content; (4) reducing environment. The results show that the pollution of heavy metals in sediment in the seawater environment depends on the behavior of both the elements themselves, but also by the external environmental conditions. Restore the environment can inhibit the release of heavy metals, contribute to the system to clear the original heavy metal out of the water column. Under low productivity, Pb and Zn showed release behavior, while under high productivity and high suspended matter content, Pb and Zn showed the first release and then the second and the Cd and Cu showed the opposite image. The net fluxes of four heavy metals released and transported during the experiment were studied. The net fluxes of Cu and Zn were 1 ~ 2 orders of magnitude higher than those of Cd and Pb under the oxidation condition. Studies have shown that adding clay and dumping to the reducing environment all help to reduce the secondary pollution of heavy metals after the dumping of contaminated sediments