黔西北土法炼锌废弃地植被重建的限制因子

以土法炼锌废弃地的废渣、污染土壤和背景土壤为基质材料，分别种植黑麦草(Lolium perenne)和三叶草(Trifolium pretense)，分析各种基质的基本化学特性、重金属(Pb、Zn、Cd)含量及其赋存形态、两种植物生长特性.结果表明，土法炼锌废渣上植被重建的主要限制因子包括高盐碱胁迫、有机质含量低、养分缺乏(TN、碱解N、TK).废渣重金属含量高，有效态含量低，对植物毒性小，但存在潜在危害性.污染土壤重金属含量低于废渣，但生物有效态重金属含量高.污染土壤植被重建的限制因子包括重金属毒性、P和K的有效性.废渣与污染土壤混合是土法炼锌废弃地基质改良的有效途径.

Limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou

With indigenous zinc smelting waste residue,contaminated soil and background soil as test substrates,a pot experiment was conducted to study the growth characteristics of Lolium perenne and Trifolium pretense on these substrates.The results showed that the major limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou were the salt-alkali stress and the lower contents of organic matter,total N,available N and total K.The heavy metals in waste residue had a high concentration,but their available forms only occupied a small proportion,with low toxicity to plant but having potential harmful risk.Contaminated soil had lower concentrations of heavy metals than waste residue,but its contained heavy metals were more in available form.The constraints of revegetation on contaminated soil were the toxicity of heavy metals and the low contents of available P and K.Mixing contaminated soil with zinc smelting waste residue could be one of the effective approaches for the substrate amendment in indigenous zinc smelting areas.