Decrease Risk of Pb Contamination in Soil-tobacco Systemby Amendments

Pot experiment using tobacco field soil was conducted to study the effect of four types amendments of lime, humic acid, sodium sulfide and organic manure on the content of Pb in tobacco and available Pb in soil. The results showed that the content of Pb in tobacco leaves treated with different amendments was proportional to the activity of Pb in the soil, and that the activity of Pb in the soil was obviously inhibited, thus significantly reduced the Pb accumulation in tobacco leaves, and the decrement rate ranged from 23.16% to 59.71%, with treatments and comparisons reaching significant difference. Based on the decrease effect of Pb in soil-tobacco system and the economic ben-efits of tobacco production, it was concluded that 2.25 t·hm-2 of lime, 2.25 t·hm-2 of humic acid or 22.5 t·hm-2 of organic manure could effec-tively decrease the Pb risk in soil-tobacco system by factor sequence generation method