长三角滨海沉积物中硫的形态转化机制及其生态效应

项目名称： 长三角滨海沉积物中硫的形态转化机制及其生态效应

项目编号： No.40871216

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 轻工业、手工业

项目作者： 高效江

作者单位： 复旦大学

项目金额： 51万元

中文摘要： 本项目重点开展了长江口区域滨海沉积物中还原无机硫化物（RIS）的形态分布特征、影响机制及其对重金属的生态效应研究，丰富了我国硫生物地球化学研究内容。主要研究成果包括：1）建立了冷扩散三步连续提取沉积物中三态还原无机硫化物方法体系，对酸挥发硫（AVS）、黄铁矿硫（CRS）和元素硫（ES）进行了定量分析。2）揭示了长江口地区滨海沉积物种RIS及其形态的空间分布特征。CRS是沉积物中RIS的主要赋存形态。RIS在崇明东滩呈现：高潮滩>中潮滩>低潮滩，垂向分布特征差异较大，同时存在一定的季节性变化规律。3）模拟实验研究表明水分条件是影响沉积物中三态还原无机硫迁移转化的重要因素，水分含量与AVS、活性铁存在正相关性；ES是沉积物中AVS转化成CRS的主要限制因子。盐度不是影响沉积物中还原无机硫形态转化的直接控制因素。4）基于SEM/AVS比值对重金属的潜在生物毒性风险进行了评价，表明江苏沿海表层沉积物的重金属潜在生物毒性风险明显高于上海沿岸，崇明东滩基本不存在重金属风险。5）比较沉积物中重金属的赋存形态和SEM的组成，发现用SEM/AVS的比值作为评价指标时，放大了重金属的生物毒性风险水平。

中文关键词： 长江口；沉积物；还原无机硫；形态；重金属

英文摘要： In the project, the distribution, speciation of reduced inorganic sulfur and its effect mechanism in intertidal sediments of the Yangtze estuary and coastal zone were studied. The main research results include the following: 1) Established a three-step series by the cold diffusion methods to analyze the three forms of RIS, such as acid-volatile sulfide (AVS) , chromium(Ⅱ-reducible sulfide (CRS) and elemental sulfur (ES) in sediments. 2) Spatial distribution and speciation of RIS in sediments were different in the south bank (shanghai coast ) and the north bank (Jiangsu coast) of the yangtze estuary. CRS is the main form of RIS in sediments, generally, speciation of RIS showed that: CRS> AVS > ES, high tidal flat > middle tidal flat > low tidal flat.3) Water content is the key factor to control the transformation of three forms of RIS in sediments. Also, ES may be the dominated matter during processes of AVS transferring to CRS. 4) Based the simultaneously extracted metals (SEM) and AVS values, the heavy metal risk assessment indicated that heavy metals in intertidal sediments of the Jiangsu coat have higher potential ecology risk level than that of the Shanghai. In addition, comparing the different form content of heavy metals with the SEM, results showed that the heavy metal ecological risk was enlarged by SEM/AVS as the assessment index.

英文关键词： the Yangtze estuary; sediment;reduced inorganic sulfur (RIS); speciation; heavy metals