0023-6152

AA00697606

4579

査読無

0023-6152

AA00697606

We have alternated the 3-week cultivation of corn (Zea mays L.) and that of Indian mustard (Brassica juncea (L.) Czern) in a pot with the sequential rotation, corn-Indian mustard-corn-Indian mustard, in order to remove Cd from two actual soils polluted with Cd and Zn, one (low Cd) polluted (LP) containing 6.5mg Cd kg[-1] and 715mg Zn kg[-1] and another (high Cd polluted (HP)) with 13.6mg Cd kg[-1] and 836mg Zn kg[-1]. Fertilizer applications to soil in a rotational cropping can nihibit the decrease in the phytoextraction efficiency. As the total of the all cultivations, the Cd removal from the soils was 2.1% of the total soil Cd cases, 0.57% in the LP plot and 0.17% in the HP plot, whereas the Zn removal was lower than the Cd cases, 0.57% in the LP plot and 0.17% in the HP plot, respectively. The Cd absorptions by both plants were significantly greater in the metal-added soils than in the actual polluted soils in all cultivations (p<0.05). This would be caused by the high concentrations of exchangeble Cd in the added soils. These results indicated that the use of metal- added soils is likely to overestimate the efficiency of some plants in phytoexraction experiments involving actual polluted soils with its variationi by the experimental conditions.