新型土壤改良剂对水稻吸收累积Cd、Pb的影响初探

在盆栽条件下研究了一种新型土壤改良剂(商品名:农大夫-地保2号,又名土壤还原素)对两种污染土壤(潮泥田和红黄泥)水稻吸收累积Cd、Pb的影响.结果表明,施用土壤改良剂能显著提高潮泥田和红黄泥的土壤pH值,降低土壤有效态Cd、Pb及水稻糙米Cd、Pb含量.当土壤改良剂施用量达到8 g/kg时,两种土壤的pH值均显著高于对照(H-0).当土壤改良剂施用量达到4 g/kg时,潮泥田土壤有效态Cd含量低于对照30.8%(P＜0.05);当其施用量增至8 g/kg时,土壤有效态Pb含量比对照降低21.9%(P＜0.05),同时水稻糙米Cd、Pb含量比对照降低18.4%(P＜0.05)和20.3%(P＜0.05).当土壤改良剂施用量达到8 g/kg时,红黄泥土壤有效态Cd、Pb分别低于对照30.7%(P＜0.05)和24.4%(P＜0.05),而其水稻糙米Cd、Pb含量在土壤改良剂施用量为4 g/kg时降幅达22.8%(P＜0.05)和24.2%(P＜0.05).综合分析认为,施土壤改良剂能显著降低污染土壤上水稻糙米的Cd、Pb累积,其效果与土壤改良剂用量、土壤pH值及土壤Cd、Pb含量有关,可能对酸性土壤更有效.

Effect of New Soil Amendment on Absorption and Accumulation of Cd and Pb by Rice

Pot experiments were conducted to study the effects of a soil amendment(trade name:Nong Dafu-Di Bao 2,also known as soil reducing agent)on absorption and accumulation of Cd and Pb by rice in polluted reddish yeHow paddy soil(RYPS)and alluvial loamy paddy soil(ALPS).The results showed that applying soil reducing agent could remarkably improve the PH values of RYPS and ALPS,and decrease the contents of available Cd and Pb in soil and Cd and Pb in brown rice.When applying amount of soil reducing agent reached 8 g/kg.the PH values of both kinds of soil were significantly higher than that of control(H-O).When applying amount of soil reducing agent was 4 g/kg,the available Cd content in ALPS was 30.8%(P＜0.05)lower than that of control,and the contents of Cd and Pb in brown rice from RYPS decreased by 22.8%(P＜0.05)and 24.2%(P＜0.05),respectively.When applying amount of soil reducing agent reached 8g/kg,the available Pb content in ALPS was 21.9% lower than that of control(P＜0.05),the contend of Cd and Pb in brown rice from ALPS were 18.4%(P＜0.05)and 20.3%(P＜0.05)lower than that of control,respectively,and the available contents of Cd and Pb in RYPS were 30.7% (P＜0.05)and 24.4% lower than that of control,respectively.It might be concluded that the application of soil reducing agent can significantly reduce the accumulation of Cd and Pb in brown rice from polluted soft;the reducing effect related to the applying amount of soil reducing agent,the pH value of soil and the contents of Cd and Pb in soil.and it might be more effective to acid soil.