外源乙酸和EDTA对铜尾矿矿砂中芦苇幼苗生长及部分金属元素积累的影响

Effects of exogenous acetic acid and EDTA on growth and accumulation of some metal elements of Phragmites australis seedling in copper tailing ore

采用容器栽培方法研究了添加外源乙酸和EDTA对铜尾矿矿砂中芦苇〔Phragmites australis(Cav.)Trin.exSteud.〕幼苗地上部分及地下部分生长及部分金属元素积累的影响。结果表明:添加0.5 mmol·L-1乙酸,幼苗各部分的干质量以及耐性指数与对照差异较小;Cu、Cd、Pb、K和Na含量或显著低于对照,或与对照差异不显著。添加2.0 mmol·L-1乙酸,地下部分和地上部分的干质量最大,分别较对照提高33.7%和58.5%,耐性指数也最大,达到1.07;幼苗各部分的Cu、Cd和K含量均显著低于对照,Pb含量高于或显著高于对照,Na含量与对照差异不显著。添加0.5 mmol·L-1EDTA,幼苗各部分的干质量显著高于对照,耐性指数较对照减小19%;各部分的Cd、K和Na含量及地下部分的Cu含量低于或显著低于对照,地上部分的Cu含量以及各部分的Pb含量高于或显著高于对照。添加2.0 mmol·L-1EDTA,幼苗各部分的干质量与对照无显著差异,耐性指数较对照减小21%;各部分的Pb、K、Na含量和地上部分Cu含量以及地下部分Cd含量显著高于对照,地上部分Cd含量显著低于对照,而地下部分Cu含量与对照差异不显著。研究结果表明:添加高浓度乙酸能促进铜尾矿矿砂中芦苇生长和Pb积累;添加高浓度EDTA能显著抑制芦苇根系生长,对金属元素的积累有明显的促进作用,尤其是能够促进Cu向地上部分的运输以及地下部分对Cd和Pb的积累。

Effects of exogenous acetic acid and EDTA on growth and accumulation of some metal elements in above-and under-ground parts of Phragmites australis（Cav.） Trin.ex Steud.in copper tailing ore were studied by pot cultivation method.The results show that after adding 0.5 mmol·L-1 acetic acid,dry weights of two parts of seedlings and their tolerance indexes have a little difference with the control.And contents of Cu,Cd,Pb,K and Na in two parts are significantly lower than those of the control,or have no significant difference with those of the control.After adding 2.0 mmol·L-1 acetic acid,dry weights of under-and above-ground parts of seedlings are the biggest with increments of 33.7% and 58.5% as compared with the control,respectively,and tolerance index of seedling is also the biggest with a value of 1.07.And contents of Cu,Cd and K in two parts are significantly lower and Pb content is higher or significantly higher than those of the control,and Na content has no significant difference with that of the control.After adding 0.5 mmol·L-1 EDTA,dry weights of two parts are significantly higher than those of the control,and tolerance index of seedlings reduces by 19% as compared with the control.And contents of Cd,K and Na in two parts and Cu content in under-ground part are lower or significantly lower and Cu content in above-ground part and Pb content in two parts are higher or significantly higher than those of the control.After adding 2.0 mmol·L-1 EDTA,dry weights of two parts have no significant difference and tolerance index of seedlings reduces by 21% as compared with the control.And contents of Pb,K and Na in two parts,Cu content in above-ground part and Cd content in under-ground part are significantly higher and Cd content in above-ground part is significantly lower than those of the control,but Cu content in under-ground part has no significant difference with that of the control.It is suggested that adding high concentration acetic acid can promote growth and Pb accumulation of P.australis in copper tailing ore.While adding high concentration EDTA has an obvious inhibition effect on root growth of P.australis,but has an obvious promotion effect on metal element accumulation,especially can promote Cu transportation to above-ground part and Cd and Pb accumulation in under-ground part.