黄粉虫幼虫对城市污泥重金属的积累作用

摘要

室内采用正交试验设计进行 4 因素多水平试验,研究了温度、城市污泥和麦麸配比、饲养密度、幼虫体重对黄粉虫幼虫生长速度、死亡率以及幼虫重金属含量变化的影响,探讨黄粉虫幼虫在城市污泥中的生长状况和对城市污泥重金属的积累作用.结果表明:随着温度的升高,幼虫生长率和死亡率都呈上升趋势,饲养密度、污泥和麦麸配比对黄粉虫幼虫生长率、死亡率无显著影响;15℃、密度为O.2 g·cm-2、污泥/麸皮为1:2、幼虫体重为85.4±5.9 mg时,幼虫对Cu、Se、Hg的积累作用较显著;15℃、密度为0.4 g·cm-2、污泥/麸皮为1:0、幼虫体重为85.4±5.9mg时,黄粉虫幼虫对Cd的积累能力显著;20℃、密度为0.4 g·cm-2、污泥/麸皮为1:0、幼虫体重为34.9±4.9mg时,Zn的积累系数较大;黄粉虫幼虫对Cu、Cd、Se、Hg和Zn等重金属元素有很强的积累作用.%By using an orthogonal design, the effects of four breeding factors (temperature, larva breeding density, municipal sewage sludge to wheat-bran ratio, and larva average weight) on the growth rate, mortality and heavy metal accumulation in T.molitor larva bred on sewage sludge were investigated.The results showed that larva growth rate and mortality increased with increasing breeding temperature.However, larva growth rate and mortality were not obviously affected by breeding density, and municipal sewage sludge to wheat-bran ratio.Optimal breeding conditions for larva bioaccumulation of Cu, Se and Hg were 15 ℃,0.2 g ·cm-2, sewage sludge to wheat-bran ratio of 1∶2, and larva average weight of 85.4±5.9 mg.Those for larva bioaccumulation of Cd were 15 ℃, 0.4 g·cm-2, sewage sludge to wheat-bran ratio of 1: 0, and larva average weight of 85.4±5.9 mg.Optimal larva bioaccumulation of Zn occurs under the breeding conditions of 20 ℃, 0.4 g ·cm-2, sewage sludge to wheat-bran ratio of 1∶ 0, and larva average weight of 34.9±4.9 mg.Obvious symptoms of Cu, Cd, Se, Hg and Zn bioaccumulation were noted in T.molitor larva fed with sewage sludge.