不同改良剂降低稻米镉含量的效果

用盆栽方法,研究了大冶县镉污染土壤应用石灰、钙镁磷肥、草炭、粉煤灰、绿肥等改良剂抑制水稻吸收镉的效果,以及六个水稻品种吸收镉的差异。结果表明,水稻品种间对镉的富集能力存在显著差异;几种供试改良剂均不同程度地降低米镉含量,以施钙镁磷肥大于150 kg/100m~2最为有效,使米镉含量降低77×10~(-2)以上,低于粮食卫生标准,其后效维持一年以上。

EFFECTS OF DIFFERENT MODIFIERS ON DECREASING THE CADMIUM CONTENT OF RICE GRAIN

Under the pot culture condition. both the inhibitory effect of modifiers such as lime, calcium magnesium phosphate, turf, burned coal ash and green manure modifiers et al on the absorption of cadmium by rice and differences between rice varieties in absorbing cadmium were studied. The results showed considerable variations between rice varieties in enriching cadmium and between modifers in decreasing cadmium content of rice grain. The cadmium content of rice grain was decreased 19.9, 26.6, 35.4 percent by lime of 18.7, 37.5, 75kg/100m~2, respectively, and 30.9, 37.7 percent by the burned coal ash and turf, respectively. Application of calcium magnesium phosphate 150kg/100m~2 was, however, the most effective measure for decreasing the cadmium content of rice grain, meeting the standard of food hygiene. Therefore, application of calcium magnesium phosphate is recommedded for improving cadmium pollution in Daye and decreasing the cadmium content of rice grain.