【摘要】 用放射性同位素1 4 7Nd示踪法 ,以pH8 2的NaAc为交换态Nd的提取剂 ,研究了碳酸盐对土壤中外源Nd的交换态及生物有效性的影响。无论碳酸盐存在与否 ,加入土壤中的Nd ,99%以上均被吸附。碳酸盐在低浓度时 ,能够降低土壤中交换态Nd含量 ;碳酸盐在高浓度时 ,对交换态Nd含量影响作用不明显。实验还表明碳酸盐在 0 8～ 1 6g·kg- 1 范围内有明显降低Nd植物有效性的作用 ,浓度升高到 4 0g·kg- 1时 ,对植物吸收Nd的抑制作用不明显更多还原

【Abstract】 The effect of carbonate on the exchangeability and the bioavailability of exogenous Nd in soil were studied with 147 Nd isotopic tracer. Exchangeable Nd was extracted by NaAc (pH 8 2) 1 mol·l -1 . The results indicate, whether carbonate exists in soil or not, Nd over 99% is adsorbed intensely by soil. Low concentration carbonate reduces exchangeable Nd concentration. Furthermore, high concentration carbonate impacts little on exchangeable Nd concentration. In addition, carbonate (0 8～1 6 g·kg -1 ) in soil can restrain wheat seedlings to absorb RE. With the concentration rising to 4 0 g·kg -1 , carbonate fails in restraint.更多还原