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[目的]了解淮河(安徽段)表层沉积物重金属污染状况,并对其潜在生态危害进行评价,为淮河水体环境保护及重金属污染的修复提供科学依据.[方法]在淮河(安徽段)选取17个样点,用抓斗式采样器采集表层沉积物,采用火焰原子吸收光谱法测定铬(Cr)、镉(Cd)、铜(Cu)、铅(Pb)的含量,采用原子荧光法测定砷(As)的含量.分别采用地累积指数法和潜在生态危害指数法,对5种重金属元素进行生态危害评价.[结果]淮河(安徽段)表层沉积物中Cr、Cd、Cu、Pb和As的质量分数(后称“含量”)均值(范围)分别为69.12(21.89～114.14)、6.61(3.14～11.66)、51.73(23.77～93.63)、46.54(19.28～103.37)和0.74(0.16～2.57) mg/kg,分别是安徽土壤背景值的1.10、78.97、2.68、1.79和0.09倍,污染程度由大到小顺序依次是Cd＞Cu＞Pb＞Cr＞As.地累积指数评价结果显示:Cd的指数最高(5.72),达极高环境风险程度;Cr和As的指数分别为-0.44和-4.08,均为无环境风险,Cu和Pb的指数分别为0.84和0.26,均为低环境风险.Cr、Cd、Cu、Pb和As的潜在生态危害系数分别为2.30、396.56、8.62、9.31和0.50,其潜在生态危害程度由大到小顺序为Cd＞Pb＞Cu＞Cr＞As.各采样点多种重金属综合危害指数在197.65～738.58之间(均值为417.30),达到中等、强和很强生态危害程度的采样点分别占18％、59％和23％,重金属综合潜在生态危害程度为强.[结论]淮河(安徽段)表层沉积物中重金属(As除外)平均含量均高于安徽省土壤背景值,存在不同程度污染,其中Cd污染最严重;无论从地累积指数评价还是潜在生态危害评价来看,Cd的潜在生态危害程度最高.“,”[Objective] To understand the pollution levels of heavy metals in surface sediments of the Huaihe River (Anhui Section),evaluate their potential ecological harm,and provide scientific references for water environment protection and restoration of heavy metal pollution in the Huaihe River.[Methods] Samples of surface sediments were collected with grab samplers in 17 sampling sites of the Huaihe River (Anhui Section).Chromium (Cr),cadmium (Cd),copper (Cu),and lead (Pb) in surface sediments were tested by flame atomic absorption spectrometry,and arsenic (As) by atomic fluorescence.G eoaccumulation index and potential ecological risk index were applied to assess the ecological risks of the five heavy metals.[Results] The mean levels (range) of Cr,Cd,Cu,Pb,and As in surface sediments were 69.12 (21.89-114.14),6.61 (3.14-11.66),51.73 (23.77-93.63),46.54 (19.28-103.37),and 0.74 (0.16-2.57) mg/kg,1.10,78.97,2.68,1.79,and 0.09 times of the soil background values of Anhui,respectively,and the severity order of heavy metal pollution from high to low was Cd ＞ Cu ＞ Pb ＞ Cr＞ As.The geoaccumulation index of Cd was the highest (5.72),indicating very high environmental risk.The indices of Cr and As were-0.44 and-4.08,respectively,indicating no environmental risk.The indices of Cu and Pb were 0.84 and 0.26,respectively,indicating low environmental risk.The potential ecological coefficients of Cr,Cd,Cu,Pb,and As were 2.30,396.56,8.62,9.31,and 0.50,respectively,with a high-to-low order of Cd ＞ Pb ＞ Cu ＞ Cr ＞ As.The comprehensive ecological indices of the five heavy netals of different sampling sites ranged from 197.65 to 738.58,and the mean was 417.30.The sampling sites showing medium,strong,and very strong ecological risks account for 18％,59％,and 23％ of total,respectively,and the comprehensive potential ecological risk was strong.[Conclusion] The average levels of heavy metals,except As,in surface sediments of the Huaihe River (Anhui Section) are higher than the soil background values of Anhui Province,showing varied degrees of pollution,especially Cd.Both geoaccumulation index and potential ecological risk index indicate that Cd has the highest potential ecological risk.