3种钝化剂及其组合对小白菜镉铅含量的影响

Effects of Different Soil Amendments on the Uptake and Accumulation of Cadmium and Lead in Pakchoi(Brassica chinensis)

文章采用田间小区试验研究了在重金属污染土壤上等量(施用总量为2.5 g/kg土,即562.5 g/m2)施用石灰(L)、海泡石(S)和铁锰矿粉(FM)及其组合对土壤镉铅有效性、小白菜生物量及镉铅含量的影响。结果表明,该研究施用量下,L和LFM(石灰+铁锰矿粉)处理小白菜生物量比对照分别显著降低47.28%和41.79%。3种钝化剂及其组合均提高土壤pH值和降低土壤CaCl_(2)-Cd和CaCl_(2)-Pb含量。与CK处理相比,施用钝化剂后土壤pH值提高0.07~1.73个单位,CaCl_(2)-Cd和CaCl_(2)-Pb含量分别降低9.34%~96.89%和16.06%~78.10%;其中L处理CaCl_(2)-Cd含量降低程度最大,LSFM(石灰+海泡石+铁锰矿粉)处理CaCl_(2)-Pb含量降低程度最大。SFM(海泡石+铁锰矿粉)和LSFM处理均能显著降低小白菜地上部Cd和Pb含量,较对照两组合小白菜Cd含量分别显著降低41.29%和41.11%,Pb含量分别显著降低30.71%和46.46%。综合考虑小白菜生物量及地上部Cd和Pb含量,SFM和LSFM组合在降低小白菜地上部Cd和Pb含量的同时亦不会造成其地上部生物量显著降低。研究结果为小白菜的安全生产提供了参考依据。

A field experiment was conducted to study the effects of applying lime(L),sepiolite(S)and ferromanganese ore powder(FM)and their combinations on the availability of Cd and Pb,biomass of pakchoi and Cd and Pb content in heavy metal contaminated soil in equal amounts(the total application rate is 2.5 g/kg soil,or 562.5 g/m2).The results showed that under the application rate in this study,the biomass of pakchoi treated with L and LFM(lime+ferromanganese ore powder)was significantly reduced by 47.28%and 41.79%compared with the control,respectively.The three passivators and their combinations all increased soil pH and reduced the contents of CaCl_(2)-Cd and CaCl_(2)-Pb in soil.Compared with control treatment,the soil pH value increased by 0.07~1.73 units after application of amendments,and the content of CaCl_(2)-Cd and CaCl_(2)-Pb decreased by 9.34%~96.89%and 16.06%~78.10%,respectively.And the content of CaCl_(2)-Cd in L treatment decreased the most,and that of CaCl_(2)-Pb in LSFM(lime+sepiolite+ferromanganese ore powder)treatment decreased the most.Both SFM(sepiolite+ferromanganese ore powder)and LSFM treatments could significantly reduce the Cd and Pb content in the shoots of pakchoi.Compared to the control treatment,the application of SFM and LSFM reduced the Cd contents in the shoot of pakchoi significantly by 41.29%and 41.11%,and the Pb contents reduced by 30.71%and 46.46%,respectively.The results showed that considering the biomass and the content of Cd and Pb in the shoot of pakchoi,applying SFM and LSFM could reduce the content of Cd and Pb in the shoots of pakchoi without significantly reducing its biomass.The results of this study provide a reference for the safe production of pakchoi.