人为干预条件下油菜对镉、铬污染土壤的生物效应

On the biological effects of cadmium and chromium contaminated soil by the oilseed rape under human interventions

采用盆栽模拟试验,研究了在强化剂乙二胺四乙酸钠(EDTA)、柠檬酸(CA)和钝化剂石灰存在的条件下,土壤存在单一Cd、Cr及复合Cd、Cr污染时,甘蓝型油菜"甘杂1号"(Brassica napus L.)对Cd、Cr的吸收富集效应。结果表明:1)1.6 mg/kg的Cd和170mg/kg的Cr单一及复合污染能够促进油菜的生长;2)当Cd为1.6mg/kg、Cr为170 mg/kg时,10 mmol/kg的EDTA和CA能够有效促进油菜对Cd、Cr的吸收富集,相比对照,无论是单一还是复合污染,其Cd、Cr累积量都有显著增加,但10 mmol/kg的EDTA和CA均抑制了油菜的生长,植株的叶面出现了不同程度的失绿、发黄、脱水、脱落等症状;3)当向污染土壤中添加1.5 g/kg钝化剂石灰时,油菜各部分Cd、Cr的质量比相比对照显著下降,但对油菜的正常生长没有显著影响;4)各部分Cd、Cr质量比随添加强化剂、钝化剂的不同,有明显的变化。研究表明,"甘杂1号"油菜对低浓度Cd、Cr单一及复合污染表现出一定的耐性和吸收能力。

This article is aimed to introduce the experimental results of our pot-growing sample experiments to explore the Cd contaminant,the Cr tolerance,the uptake and accumulation of the oilseed rape under the single and compound polluted soils of cadmium and chromium,when added to the chelator EDTA and CA,and the passivator lime. The results of our experiments indicate that the single and compound Cd,and the Cr pollution can all promote the growth of the oilseed rape,when the exogenous Cd concentration is equal to 1. 6 mg / kg and Cr was 170 mg / kg,the chelator EDTA and CA of 10 mmol / kg would effectively promote the enrichment of the oilseed rape to the absorption of Cd,Cr,as compared with the control contrast samples. As we know,whether the single or compound pollution may be,its uptake would be significantly increased,but the chelators EDTA and CA of 10 mmol /kg may all likely inhibit the growth of oilseed rape. The plant foliage may produce different degrees of symptoms,such as the loss of its shade of green and yellow pigment,dehydration and so on.When adding passivator lime 1. 5 g / kg into the contaminated soil,as compared to the control group,the Cd,Cr content of each part of oilseed rape can probably be decreased significant,but they had no significant effect on the normal growth of the crop. However,it may give out a certain tolerance to Cd,Cr contaminated soil,the accumulation of Cd,Cr in the roots can all be much higher than that in its shoots and leaves. For example,when the cheaters and passivator are added,the Cd and Cr content of each part of the oilseed rape may have obviously changed. Thus,our study implies that when the soil has been polluted by the low concentration either of the single or compound content of Cd,Cr,‘Ganza 1＇may show some degree of tolerance and absorptive capacity.