Abstract:Field experiments were conducted to investigate the effects of sepiolite on the composition and stability of soil aggregates and soil organic carbon content during the processes of in situ immobilization remediation for Cd contaminated vegetable field. The results showed that the amounts of 5~8 mm and <0.25 mm aggregates under the sepiolite treatments were decreased compared with the control. However, the contents of 2~5 mm, 1~2 mm, 0.5~1 mm and 0.25~0.5 mm soil aggregates were all significantly increased with the increment of sepiolite (P<0.05). In 0—15 cm soil layers, mean weight diameter (MWD) and geometrical mean weight (GMD) of soil aggregates increased first and then decreased with the increase of the amount of sepiolite, whereas it was reduced in 15—20 cm soil layers. The concentration of soil organic carbon was reduced under the application of 0.5% sepiolite, with the maximum reduction up to 21.1%, while it was increased when the treatments of spiolite was 1% (H1) and 1.5% (H1.5), with the maximum increase of 2.9% and 70.3%, respectively, when compared with the control. The soil organic carbon contribution rate in 5~8 mm, 2~5 mm and 1~2 mm of soil aggregates was enhanced under different treatments of sepiolite.