背角无齿蚌对养殖池塘底泥释放重金属的净化效果

通过建立微型生态系统, 分析养殖池塘底泥释放重金属的特征及背角无齿蚌(Anodonta woodiana)对底泥释放重金属的净化效果。底泥对Al、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Mo和Pb的最大释放量分别为636、1.5、70.9、34951、10.3、36.9、34.0、53.2、72.4、48.8和3.0 μg·kg-1 dw; 蚌能够对Al、Cr、Mn、Co、Cu、Zn、As和Mo产生净化作用(P<0.05), 最大去除率分别可达到84.7%、98.0%、33.3%、14.3%、23.5%、69.4%、50.0%和13.0%, 响应面优化分析显示养殖密度和处理时间分别为40 只·m-3和24.49 d、25 只·m-3和23.96 d, Al和As去除率可提升至93.8%和60.5%; Al、Cr、Fe、Co、Cu、Zn、As和Mo的净化效果与养殖数量相关, Al、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Mo和Pb的净化效果与处理时间相关, Cr、Co、Ni、Cu和Zn的净化效果与两者交互作用相关(P<0.05)。提示背角无齿蚌有潜力防控池塘底泥重金属污染。

Purification capacity of Anodonta woodiana on heavy metals released from the aquaculture pond sediment

Microcosm experiments were conducted to determinate the release characteristics of heavy metals from the pond sediment,and to study the corresponding purification capacity of freshwater mussel Anodonta woodiana.The results showed that the maximum release of Al,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,and Pb from the sediment were 636,1.5,70.9,34951,10.3,36.9,34.0,53.2,72.4,48.8,and 3.0μg·kg-1 dw.The mussels could significantly lead to a decrease in the concentrations of Al,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,and Pb(P<0.05),and the highest removal efficiencies for them were 84.7%,98.0%,33.3%,14.3%,23.5%,69.4%,50.0%,and 13.0%,respectively.Moreover,analysis of response optimization showed that the removal efficiencies for Al and As could possibly be elevated to 93.8%and 60.5%respectively,if the mussel systems were assigned at density-time as 40 individual·m^-3-24.49 d,and 25 individual·m^-3-23.96 d.The purifying effects of Al,Cr,Fe,Co,Cu,Zn,As,and Mo were significantly related to mussels’culture quantity(P<0.05);and those effects of Al,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,and Pb were significantly related to mussels’treatment time(P<0.05).Additionally,the purifying effects of Cr,Co,Ni,Cu,and Zn were related to both culture quantity and treatment time(P<0.05).The present study suggests that A.woodiana has the potential capacity to prevent and control metal contamination of fish pond sediment.