南海乐东海域浅表沉积物中钡锶铬镍形态分布特征研究

Distribution of Species of Ba,Sr,Cr and Ni in Surface Sediments of Ledong Coastline,South China Sea

采用四酸消解法及改进的 Tessier 连续提取法，以 ICP-AES 技术对南海乐东海域10个浅表沉积物样品中 Ba、Sr、Cr、Ni 的总量及赋存形态进行了测定和分析。形态分析表明，Ba、Cr 以残渣态为主，潜在生物有效性较低；Sr 主要以离子交换态和碳酸盐结合态存在，两者含量之和在61.21%~90.11%之间，生物可利用性较高；Ni 主要以有机结合态与残渣态存在。Ni 的含量受沉积物中 Fe 和总有机碳（TOC）的影响，Cr 和 Ni 铁锰氧化态浓度与沉积物中 Fe 的含量有明显的相关性。

With four acid digestion method and modified Tessier sequential extraction process, surface sediment samples were investigated from ten sites in the south china sea near Ledong county, and total concentrations and different phases of Ba, Sr, Cr and Ni were analyzed by using inductively coupled plasma-optical emission spectrometry in order to assess the distribution of metals in this area. The speciation analysis showed that Ba and Cr were mostly present in residual fraction and had lower potential biological effectiveness, whereas Sr was mainly associated with the exchangeable and carbonate phases, whose sum present ranged from 61.21%~90.11%, manifesting the high biological availability. Ni was mostly bound with the organic and residual phase. The concentration of Ni was markedly affected by Fe content and TOC. There was a significant relationship between Cr and Ni concentration in the Fe-Mn oxide phase and Fe content in sediment.