太湖水体多环芳烃生态风险的空间分布

以太湖梅梁湾、贡湖湾和胥口湾水体多环芳烃(PAHs)含量水平为基础,通过物种敏感度分布曲线计算三湖湾水体PAHs对水生生物的潜在危害比例,以此表征PAHs对太湖三湖湾水体的生态风险,并对其空间分布特征进行讨论.结果表明:PAHs对太湖三湖湾水体的生态风险大小依次是:Flua(1.1641%),Phe(0.2206%),Pyr(0.1633%),BaP(0.0175%),Ant(0.0021%),Flu(0.0005%), Ace(0.0000%),∑7PAH的联合生态风险(3.0954%)大于单体PAHs的生态风险. Ant, BaP和∑7PAH对梅梁湾(0.0209%,0.1237%和4.1018%)的生态风险显著高于贡湖湾(0.0023%,0.0085%,3.0414%)和胥口湾(0.0002%,0.0015%,2.3899%)(P0.05);Flu和Phe对胥口湾(0.0004%,0.1553%)的生态风险显著低于梅梁湾(0.0011%,0.2999%)和贡湖湾(0.0009%,0.2681%)(P0.05);Pyr和Flua对梅梁湾(0.3268%,1.7156%),贡湖湾(0.1697%,1.2386%)和胥口湾(0.1044%,0.8339%)水生生物的生态风险具有显著性差异(P<0.05).空间分布表明:梅梁湾西北部PAHs的生态风险最大,贡湖湾北部次之,胥口湾最小.

Spatial distribution of ecological risk of polycyclic aromatic hydrocarbons in the surface waters of Lake Taihu

On the basis of PAHs concentrations in Meiliang Bay,Gonghu Bay and Xukou Bay of Taihu Lake,potentially affected fractions of PAHs to aquatic organisms in Lake Taihu were calculated using species sensitivity distribution.Spatial distribution of ecological risk were mapped using geographical information system.The ecological risk of PAHs to aquatic organisms was in the order of Flua(1.1641%),Phe(0.2206%),Pyr(0.1633%),BaP(0.0175%),Ant(0.0021%),Flu(0.0005%),Ace(0.0000%).The combined ecological risk caused by ∑7PAH was higher than that from individual PAHs.Ecological risks of Ant,BaP and ∑7PAH to aquatic organisms in Meiliang Bay(0.0209%,0.1237%,and 4.1018%) were significantly higher than those in Gonghu and Xukou Bay,while there was no significant difference between ecological risks in Gonghu Bay(0.0023%,0.0085%,and 3.0414%)and Xukou Bay(0.0002%,0.0015%,and 2.3899%).Ecological risks of Flu and Phe in Xukou Bay(0.0004%,0.1553%)were significantly lower than those in Meiliang Bay(0.0011%,0.2999%) and Gonghu Bay(0.0009%,0.2681%),whereas there was no significant difference in ecological risks from Flu and Phe in Meiliang Bay and Gonghu Bay.Ecological risks of Pyr and Flua in Meiliang Bay(0.3268%和 1.7156%),Gonghu Bay(0.1697%,1.2386%) and Xukou Bay(0.1044%,0.8339%) were significantly different from each other.The maps of spatial distribution of ecological risk produced by the distance inverse weight method demonstrated that the distribution characteristics of ecological risks from several individual PAHs and ∑7PAH in three bays of Lake Taihu were similar,and the ecological risk of PAHs to all the aquatic organisms in descending order of Northwestern Meiliang Bay,Northern Gonghu Bay and Xukou Bay.