The contents and distributions of acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) (Cr Cu, Zn, Cd, Pb) were studied in the surface sediments collected from the tidal flat of Donghai Island, Zhanjiang. The results indicated that at most stations, the AVS concentration was lower in summer with the average of 0.449μmol/g than in winter with the average of 1.816μmol/g. The AVS contents were higher in the southern and northern areas and lower in the western and eastern areas. The average contents of移SEM were between 0.56μmol/g and 4.60μmol/g in summer and between 0.65μmol/g and 2.21μmol/g in winter. The concentration change of single metal was Zn>Cr>Pb>Cu>Cd at most stations. The content percentages of 移SEM were below 1 % for Cd and over 70 % for Zn. SEMZn was the key pattern to control the distribution of移SEM due to its high percentage of concentration. Based on the assessment methods of (移SEM/AVS) and (移SEM-AVS) and the thresholds for the metal toxicity to the benthic organism, most value of (移SEM-AVS) in the tidal flat of Donghai Island was between 0 and 5. The most toxicity region was in Tongminghai area located in the west tidal zone of Donghai Island, and the most toxicity metal was zinc in summer in Tongminghai area.%对湛江东海岛潮间带表层沉积物中酸可挥发性硫化物（AVS）和同步提取重金属（SEM）的含量及其分布进行了研究。研究表明，东海岛潮间带表层沉积物中AVS含量夏季平均为0.449μmol/g，冬季为1.816μmol/g，大多数站位AVS含量冬季高于夏季；AVS平均含量总体呈南、北区较高，东、西区较低的区域分布规律。潮区沉积物可提取重金属SEM总量夏季在0.56~4.60μmol/g之间，冬季处于0.65~2.21μmol/g之间；各重金属平均含量大小为Zn>Cr>Pb>Cu>Cd，其中Cd含量占SEM总量不到1%，Zn含量则在70%以上，SEMZn是控制着SEM分布的主要模式。联合利用（移SEM/AVS）与（移SEM-AVS）法和生物毒性阈值法综合评估重金属对沉积环境的影响，东海岛潮间带大部分区域沉积物中（移SEM-AVS）处于0~5之间，重金属潜在生物毒性较强的区域为通明海区（7号站和8号站所在），具有较强潜在生物毒性的重金属为夏季通明海区的Zn。
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