中文摘要：

对东寨港红树林湿地沉积物中7种典型重金属元素（Cr、Ni、Cu、Zn、As、Cd和Pb）的有效态含量和全量进行测定,并讨论了红树林湿地沉积物中重金属元素的分布特征及其生物有效性.结果表明：7种重金属在东寨港红树林湿地的含量大于亚龙湾和三亚湾的红树林湿地,但与中国南方和世界各地的典型红树林湿地相比仍处于中等偏低水平.东寨港红树林湿地光滩、林缘、林内表层沉积物的重金属含量存在差异;在柱状沉积物中重金属伴随沉积明显,表现出较强的同源性.经EDTA萃取出的有效态金属在表层沉积物中含量依次为Cu〉Cr〉Zn〉Ni〉As〉Pb〉Cd;垂直梯度重金属有效态含量占总量的比例的最大值（除Ni外）均出现在表层或中上层;目标重金属元素有效态和总量在空间分布上具有明显正相关性,元素总量指标能较好地评估该元素的生物有效性.

英文摘要：

In this study, total and available contents of seven typical heavy metals （Cr, Ni, Cu, Zn, As, Cd and Pb） were determined in mangrove wetland sediments in Dongzhai Harbor, and the distribution characteristics and bioavailability of these heavy metals in sediment were analyzed. The results showed that all the metals contents in this area were higher than in mangrove wetlands in Yalong Bay and Sanya Bay, but lower than the average level in mangrove wetlands in South China and other areas in the world, which was at a moderate to low level. The contents of heavy metals in surface layer of sediment significantly differed among barren shoal, the edge and inside of forest. All the metals were obviously accompanyingly deposited in the columnar sediments, which indicated a strong homogeneous source. The available contents of seven heavy metals in the surface sediments were extracted by EDTA, which had the order of Cu〉Cr〉Zn〉Ni〉As〉Pb〉Cd. All the maximum ratios of available to total content of elements appeared There was significant positive correlation between in surface or middle to upper layers, except Ni. available and total contents of target metals.