大田条件下不同土壤钝化措施对稻米镉吸收的影响

Effects of Different Soil Passivation Measures on Cadmium Uptake of Rice under Field Conditions

大田条件下与盆栽试验相比具有更多的不可控因素。本文选择几种已经报道有效且简便易行的镉污染钝化修复技术,在四川省典型区域大田栽培条件下进行了试验验证。结果表明,在土壤镉轻度污染的LZ地区,稻米镉含量也较低,且均低于GB2762-2012标准限值,各处理与常规处理间稻米镉含量未表现出较明显差异。在土壤镉含量中、重度污染的GH和XC地区,施用调理剂处理和石灰处理,稻米镉含量下降20%~60%,2种处理方式效果相当;相对常规处理,施用有机肥处理的稻米镉含量有增有减,其原因尚待进一步探究。

Compared with the pot experiment,the test under field condition has more uncontrollable factors. Several reportedly effective and simple soil cadmium contamination passivation techniques were chosen,and the experiment was carried out to verify in a typical area of Sichuan province under field cultivation in the present paper. The results showed that in LZ regions lightedly polluted by cadmiumin in soil,rice had a low cadmium content,averagely lower than the standard limit of GB 2762-2012,and the cadmium content in rice showed no obvious differences among all kinds of treatments and conventional treatments. In GH and XC regions respectively moderately and heavily contaminated by cadmium contentin in soil,applying conditioner or lime,rice cadmium content decreased by 20 %- 60 %,the effects of these two approaches were quite the same; Contrasted with conventional treatment,the cadmium in rice by organic fertilizer increased and decreased,and the reason should be further explored.