土壤性质对烟草中镉富集的影响及预测模型研究

Studies on Effects of Soil Properties on Cd Accumulation in Tobacco and Prediction Model

利用15个不同性质的土壤进行盆栽试验,研究了土壤性质对烟草中镉(Cd)富集的影响及预测模型。结果表明,影响烟草中Cd的主要土壤因素依次为土壤Cd浓度、pH、有机质含量。酸性土壤中烟草对土壤Cd具有较强的富集作用。外源Cd比土壤中原生Cd更容易被烟草吸收。土壤基本性质与烟草Cd浓度的数量关系为:Log[烟草Cd]=3.04+1.212Log[土壤Cd]-0.270pH-0.264Log[OC],利用此方程能够很好地预测烟草中Cd浓度。通过降低土壤中Cd的浓度或有效性,提高土壤pH等措施可有效降低烟叶中Cd的浓度。

The accumulation of cadmium （Cd） in tobacco （Nicotiana tabacum L.） as affected and predicted by soil properties was investigated using 15 soils with a wide of properties and pot experiments. Results indicated that the main soil factors affecting the accumulation of Cd in tobacco were in the following order： soil Cd concentration, pH and organic matter content. The accumulation of Cd in tobacco plants in acidic soils was greater than that in alkaline soils. Also, it was found that exogenous water soluble Cd added to soils was more easily absorbed by tobacco compared with Cd in soils. The quantitative relationship between concentration of Cd in tobacco plants and soil properties was log [Plant Cd] = 3.041 ＋ 1.212Log [Soil Cd] - 0.270pH - 0.2641og [Organic carbon], which could be used to predict well the concentration Cd in tobacco plants based on soil Cd, pH and organic carbon content. Meanwhile, the results showed that the concentration of Cd in tobacco plants could be significantly reduced by increasing soil pH and decreasing concentration of soil Cd.