不同农作物对根际土壤环境及铜的形态转化的影响

采用盆栽试验研究了在重金属污染土壤中种植几种常见农作物对根际土壤理化性质、Cu的形态转化及植物有效性的影响。结果表明，种植作物引起根际土壤有机质、CEC的增高和pH值的下降，同时也导致了不同作物根际Cu含量的增高及其形态转化的差异。相对于非根际土壤，8种农作物根际土壤中Cu含量都相应地增加了4．8％～14．3％，可交换态Cu的增量十分明显，增量最高的作物——水稻达到900％以上，大部分作物氧化物态Cu也增加了20％左右，而其他各态，不同作物的变化趋势有所差异；对Cu的形态与农作物Cu含量的相关性分析表明，碳酸盐态Cu的植物有效性较大。研究表明，种植作物并没有改变根际土壤Cu的基本赋存状态。

Effects of Different Crops on the Rhizosphere Soils and Copper Transformation

Root-box experiments were used to study the effects of several crops on rhizospheric environment,Cu form transformation and phytoavailability. The results revealed that, by cultivating crops,the organic matter and the CEC of rhizosphere soils increased and pH decreased; Cu in rhizosphere soils was higher than that of non-rhizosphere soils by 4. 8 - 14.3 percent; the exchangeable Cu increased significantly over 900 percent by rice. The average increment of oxide bound Cu was about 20 percent and the other forms changed irregularly. Correlative analysis showed that carbonate bound Cu was more bio-available. The Cu basic forms were similar between rhizosphere and non- rhizosphere soils.