不同钝化材料对红壤中铜有效性的影响及机理

选取3种钝化材料（赤泥、硼泥、钙镁磷肥）,通过盆栽试验,观测了在不同铜污染水平红壤上,3种钝化材料对小油菜（Brassica campestris,L var Conmunis）吸收铜的影响。结果表明：在铜污染红壤上,3种钝化材料降低土壤EDTA提取态铜含量的效果显著。其中,在高铜污染水平红壤上,施用高量赤泥、硼泥处理降低效果最为明显,较污染对照降低了41.48%、44.44%。在低铜污染水平红壤上,施用高量赤泥处理降低效果最为明显,较对照处理降低了35.83%。施用3种钝化材料均能促进小油菜生长,增加小油菜的生物量,降低小油菜对铜的吸收量。其中,低铜污染水平红壤上,施用高量赤泥、高量硼泥与硼泥-赤泥联合施用处理降低铜含量的效果最为明显,与污染对照相比,小油菜铜含量分别降低82.64%,72.71%,85.14%;在高铜污染水平红壤上,施用高量赤泥与硼泥、赤泥联合施用处理降低小油菜铜含量的效果最为明显,小油菜铜含量分别为36.37,36.32 mg.kg^-1。结果表明,用量为45 000 kg.hm^-2的赤泥是最佳的功能钝化材料。

Mechanism and effects of different amendments on copper uptake by rape

A pot experiments was conducted to investigate the effects of three amendments（red mud,boron mud and calcium magnesium phosphate） on copper（Cu） uptake by rape（Brassica campestris,L） and on copper availability in red earth.The results showed that all amendments could significantly decrease the EDTA-extracted Cu concentrations in Cu contaminated soil.Compared to the control,the application of high doses of red mud（45 t.hm^-2） and boron mud（30 t.hm^-2） in the red soil contaminated by a high level of Cu significantly reduced the concentration of EDTA-extracted Cu up to 41.48%,44.44%,respectively.In general,the addition of amendments can all increase the dry weight of rape and reduced Cu uptake by rape.Compared with the control the addition of red mud（45 t.hm^-2）,boron mud（45 t.hm^-2） and mixture of red mud and boron mud（15 t.hm^-2） to the red soil contaminated by a low level of Cu significantly reduced the Cu concentration in the aboveground of rape by 82.64%,72.71% and 85.14% respectively.After the supplementations of red mud（30 t.hm^-2） and the mixture of red mud and boron mud（15 t.hm^-2）,the concentrations of Cu in the aboveground of rape decreased to 36.37 mg.kg-1 and 36.32 mg.kg-1,respectively,in the red soil contaminated by a low level of Cu.In this study,the red mud supplied with a dosage as 30 t.hm^-2 showed the highest efficiency to reduce the concentration of EDTA-extracted Cu and the Cu accumulation in rap.