海洋重金属在固液两相的分配及其富集研究

Study on Distribution and Enrichment of Marine Heavy Metals in Solid-liquid Two-phase System

为研究重金属在固液两相的分配情况及影响因素,在钦州近岸海域分别采集了33个海水、悬浮颗粒物及沉积物样品,对应分别测定了溶解态、颗粒态及沉积物中Zn、Cu、Pb、Cd、Cr等5种重金属,并通过溶解态重金属在固液两相重金属总量的比例和相关性分析,探讨了重金属在海水环境中固液两相的分配及其富集,比较分析了悬浮颗粒物和沉积物对各重金属的富集能力.结果表明,在海湾区域Zn、Cu、Pb、Cd以溶解态为主,在入海口区域Cr以颗粒态为主;研究区各溶解态重金属在固液两相重金属总量所占比例从大到小依次为:Zn(78.46%)>Cd(73.33%)>Cu(59.44%)>Pb(48.28%)>Cr(29.75%);pH或盐度的增大及总悬浮颗粒物的减小都会使海水环境中Zn、Cu、Pb、Cd、Cr的分配平衡向溶解态移动;沉积物对各重金属的平均富集作用Cr(18.18)>Cu(4.04)>Pb(3.58)>Cd(2.47)>Zn(1.51);悬浮颗粒物对各重金属的富集能力大于沉积物.

In order to study the distribution of heavy metals in the solid-liquid phase and the influencing factors,in the coastal waters of Qinzhou 33 samples of seawater,suspended particulates and sediments were collected,whose Zn,Cu,Pb,Cd and Cr were respectively determined in dissolved state,particulate state and sediments,and the distribution of heavy metals in the solid-liquid two-phase system in seawater environment and its enrichment were discussed.The results showed that the dissolved state of Zn,Cu,Pb and Cd was dominant in the Bay area,and the particle state of Cr was dominant in the estuarine area,and the proportion of dissolved heavy metals in the total amount of solid-liquid two-phase heavy metals in the study area was:Zn(78.46%)>Cd(73.33%)>Cu(59.44%)>Pb(48.28%)>Cr(29.75%);the increase of pH or salinity and the decrease of total suspended particulate matter(TSP)would shift the distribution equilibrium of Zn,Cu,Pb,Cd and Cr to the dissolved state in seawater.The average enrichment of heavy metals by sediments showed Cr(18.18)>Cu(4.04)>Pb(3.58)>Cd(2.47)>Zn(1.51),and the enrichment ability of suspended particulate matter to heavy metals was higher than that of sediments.