【摘要】 对广西山口红树林国际重要湿地表层沉积物重金属含量进行测定和分析,并采用单因子指数法和H?kanson的潜在生态风险指数法对重金属的污染特征及潜在生态风险性进行了评价。结果表明:山口红树林湿地表层沉积物6种重金属的平均含量均低于国家海洋沉积物一类标准,总体污染程度为"轻";从潜在生态风险空间分布特征看,2#和10#站位的潜在生态风险指数分别为137. 22和144. 10,为中潜在生态风险,其他站位表现为低潜在生态风险;山口湿地沉积物重金属总体潜在生态风险程度低,各重金属元素的潜在生态风险程度由高到低依次为Cd>Hg>Pb>Cr>Cu>Zn,其中Cd为主要潜在生态风险因子;统计分析结果表明,Cr、Cu和Zn这3种重金属元素之间具有极正相关性,结合因子分析和实地调查结果推测:Cr、Cu和Zn来源主要是人类活动,养殖排污和生活污水为主要来源。更多还原

【Abstract】 The surface sediments of Shankou mangroves nature reserve were sampled and the heavy metal contamination was monitored. Distribution and contents of the heavy metals were comparatively analyzed in this study. The pollution and ecological risk assessment of heavy metals in the surface sediments was investigated by applying the single factor index and H?kanson potential ecological risk index.The results showed that the average contents of heavy metals Hg,Cu,Pb,Zn,Cd,Cr were lower than the first level of heavy metals in marine sediment regulated in the GB 18668-2002. The overall contamination level of heavy metal in the surface sediments of Shankou mangroves nature reserve was intermediate. According to the spatial distribution characteristics of potential ecological risks,the potential ecological risk indexes of stations 2 and 10 were 137. 22 and 144. 10,which were medium potential ecological risks,while the other stations were slight. The overall level of potential ecological risk of heavy metals in the sediment was low,while the potential ecological risk of heavy metals followed the order:Cd>Hg>Pb>Cr>Cu>Zn. Cd was the key factor of potential ecological risk. The statistical analysis results showed that there were strong correlations among heavy metals such as Cr,Cu and Zn in the surface soil of Shankou mangrove wetland. Cr,Cu and Zn are mainly derived from human activities,and sewage from aquaculture and domestic sewage are the main sources.更多还原