Cd、Pb污染对几种叶类蔬菜生长的影响及其毒害症状

通过生物盆栽试验,研究了重金属Cd、Pb污染对3种叶类蔬菜(青菜、白菜、菠菜)生长的影响.结果表明,1)重金属污染对叶类蔬菜生长的影响及毒害症状因重金属种类和蔬菜品种而异.其中青菜对Pb污染敏感性最低,仅在高浓度污染时才表现出生长抑制作用.较低浓度Cd、Pb对蔬菜生长还具有一定促进作用.青菜、白菜和菠菜体内Cd累积量与土壤中Cd投加量呈显著线性关系(r2分别为0.995、0.992、0.958);2)蔬菜在不同重金属污染浓度下的吸收和富集能力存在差异.青菜和白菜在300mg·kg-1Cd投加量时表现出最大的富集能力(p<0.05).Pb处理下,白菜Pb富集系数始终低于青菜和菠菜,青菜的最大Pb富集系数出现在Pb投加量为2900mg·kg-1时;而菠菜则在Pb投加量1500mg·kg-1时表现出最强的Pb富集能力.

Impacts of Cadmium and Lead Pollution in Soil on Leaf Vegetables Growth and Toxic-Symptoms

The impacts of heavy metals(Cd and Pb)pollution on leaf vegetable(Brassica chinensis, Brassica pekinensis Rupr and Spinacia oleracea L.)growth and toxic-symptoms were studied. The results indicated that toxicity to vegetables and its symptoms were different with different heavy metals and vegetable varieties. These vegetables were not sensitive towards soil Cd and Pb pollution and low concentrations of Cd and Pb promoted vegetable growth. There was a significant linear relationship between Cd contents of soil and that of vegetables(r2 is 0.995, 0.992 and 0.958, respectively). It was found that in different polluted soils vegetables had different enrichment coefficients. It is suggested that vegetables that have low enrichment coefficients should be selected for plantation, in order to reduce the content of heavy metals in vegetable food chain.