有机物料对土壤镉形态及其生物有效性的影响

采用盆栽试验，研究了淹水种稻条件下添加猪粪和泥炭对红壤和潮土中内源和外源Cd形态及其生物有效性的影响。结果表明，土壤中内源Cd在各形态之间的分布比较均匀；添加外源Cd时Cd主要分布于交换态，从分蘖期到成熟期，内源Cd交换态普遍升高，添加外源Cd时交换态普遍降低。有机物料对内源Cd交换态的影响不显著，但当添加外源Cd时则对交换态有显著影响，在不添加外源Cd的条件下，有机物料普遍促进水稻根系对Cd的吸收。在添加外源Cd的条件下，有机物料普遍抑制水稻根系对Cd的吸收，猪粪的抑制效果强于泥炭，水稻根系对Cd与Fe的累积呈显著抑制作用。

Effects of organic manure on the conformation and biological availability of soil Cd

Pot experiments were conducted to investigate the effect of organic manure on the conformation and availability of both native and added Cd in red soil and moisture soil under rice planting. Most of the added Cd existed in exchangeable form, while the native Cd existed more evenly in four forms. The organic manure did not influence apparently on the forms of native Cd,whereas influenced significantly on those of the added Cd. From tillering to mature stage, the exchangeable form of the native Cd increased, while that of the added Cd decreased. The application of organic manure could promote the uptake of Cd under the treatments without adding Cd. Under the treatments of adding Cd,the application of the organic manure could depress the uptake of Cd,and the effect of applying pig's manure was stronger than that of applying peat. There existed a significant antagonism between the accumulation of Cd and Fe in rice roots.