土壤镉处理对棉花镉吸收及分布规律的影响

用CdCl2将盆栽土壤Cd浓度处理为1mg／kg、5mg／kg、10mg／kg、20mg,／kg、30mg／kg种植棉花，研究棉花对镉的吸收及镉在棉花体内的分布规律。结果表明，当土壤镉浓度小于30mg／kg时，镉在棉花体内的分布呈现不同的规律。当土壤镉浓度小于5mg／kg时，镉主要分布在棉花的地上部；当土壤镉浓度大于20mg／kg时，镉主要分布在棉花的叶片、根、茎中，其中叶片的镉含量最高，棉絮镉含量最低。不同镉污染水平下，棉花的镉富集系数均小于1。当土壤镉污染浓度为5mg／kg时，棉花叶片的镉富集系数为0．76。在同一镉污染水平下，棉花叶片的镉转运系数最高。当土壤镉含量小于20mg／kg时，棉花茎、叶、棉絮的转运系数平均为4．63。

Study on Uptake and Distribulion of CA in Cotton

The soil was treated by CdCl2, the cadmium concentration was l mg/kg, 5mg/kg, 10mg/kg, 20mg/kg, 30 mg/kg respectively. Then the cottons planted in pot in order to study uptake and distribution of Cd in cotton. The results showed that the cadmium distribution were great different in the cotton plants different parts while the soil cadmium concentrated less than 30mg/kg. The cadmium element mainly concentrated in cotton＇ s overgrown parts when the soil Cd concentration was less than 5mg/kg, when the soil cadmium concentration was higher than 20mg/kg, the cadmium mainly concentrated in cotton leaves, roots, stems, but the cadmium concentration of leaves was the highest, and Cd concentration of cotton fiber was the lowest. Cd enrichment factor of cotton was less than 1 under different treatments, when the soil concentration of cadmium was 5mg/kg,the cotton leaf cadmium concentration coefficient was 0.76. The cadmium transfer coefficient of cotton leaf was highest under the same CA treatment. The average transfer coettlcient of cotton stems,leaves,fiber was 4.63 when the soil cadmium contentraton was less than 20mg/kg.