外源稀土在根际与非根际土壤中的存在形态

采用根际袋法研究了稀土在春小麦根际土壤与非根际土壤中存在形态的差别.结果表明,外源稀土进入土壤后,在根际土壤与非根际土壤中主要以残渣态形式存在,各形态含量的大小顺序为:残渣态>碳酸盐结合态>可交换态>铁锰氧化物结合态>有机质结合态.小麦根系活动明显影响根际土壤中的稀土存在形态,根际土壤中的可交换态和铁锰氧化物结合态含量明显大于非根际土壤中的含量,而碳酸盐结合态有所下降,有机质结合态无明显变化.

Existent state of outside source rare earth elements (REEs) in rhizosphere soil and irrhizosphere soil

Existent state variation of rare earth elements (REEs) in wheat rhizosphere and non-rhizosphere soils were studied using root- box technique. Results showed the elements added into both soils existed mainly in state of residua. The contents of various states are: residual >carbonate bined > exchangeable > iron/manganese oxide bined > organics binded. The states were markedly influenced by the root activation. Content of exchangeable and iron/manganese oxide binded in rhizosphere was obviously higher than that in non-rhizosphere soil. Content of carbonate binded decreased, while that of organics binded did not change obviously.