钙镁磷肥对土壤中镉形态转化与水稻吸镉的影响

酸性镉污染水田施用不同用量的钙镁磷肥的田间试验表明:土壤中交换态镉的分配系数随钙镁磷肥用量的增加而降低,呈显著负相关(r,-0.9314);碳酸盐结合态和铁锰氧化物结合态镉的分配系数则呈显著正相关(r,0,9395)。而土壤中有效态镉含量与钙镁磷肥用量则呈显著负相关(r,-0.8853)。镉污染水田一次性投加高量钙镁磷肥后,可使土壤pH显著升高,交换态镉分配系数明显下降,碳酸盐结合态和铁锰氧化物结合态镉分配系数明显升高,导致土壤中有效态镉含量大幅度下降,从而大大减少水稻植株的吸镉量。

EFFECT OF CALCIUM MAGNESIUM PHOSPHAT FERTILIZER ON CHEMICAL FORMS AND TRANSLOCATIONS OF CADMIUM AND CADMIUM UP-TAKING BY RICE IN SOIL

The various amount of Calcium Magnesium Phosphote fertilizer (CMPF) was incorporated in the acid paddy fields by Cadmium-polluted, The results showed that the partition coefficient of exchangeable Cd in the soil decreased with increase of the amount of CMPF. Negative correlation coefficient reached at sighificant level (r=-0.9314), Oppositely, the partition coefficient of carbonate bound Cd, Fe/Mn oxides bound Cd was evidently positive correlation (r=0.9294), The pH of the soil was close related to the amount of using CMPF (r=0.9395), The amounts of bioavailability Cd was evidently negatively related to the amount of CMPF in the soil (r=-0.8853) , A lot of CMPF was applied in rice-fields by Cd-pollution in a lump, The pH of the soil rised evidently, The partition coefficient of exchangeable Cd decreased significiently, the partition coefficient of carbonate bound Cd, Fe/Mn oxides bound Cd increased evidently. Thus results in the concentration of the bioavailaility Cd in the soil decreased by a big margin. The Cdconcentration for rice plants decreased significiently.