[DA-6 and GLDA Enhanced L. to Phytoextract Cd from Contaminated Soils].

To reveal the effects of diethyl aminoethyl hexanoate (DA-6) combined with L-Glutamic acid, -diacetic acid (GLDA) on the remediation of Cd contaminated soils by L., different GLDA application methods with total application doses of 600, 1200, and 2400 kg·hmequally divided 1, 2, and 4 times, respectively, were studied on the basis of DA-6 concentrations of 0 and 10 μmol·L, and application intervals (2 and 4 times) were 30 and 15 days, respectively, over 60 days. Soil pH, dissolved organic carbon (DOC), biomass and Cd contents, Cd extraction, total Cd, and available Cd (DTPA-Cd) were analyzed. The results showed that first, the combination of DA-6 and GLDA could improve soil pH and DOC, and the pH and DOC increased significantly with increased GLDA application. Secondly, the combination of DA-6 and GLDA could significantly improve the biomass and Cd contents of L., and for DA-6, the amounts and times of GLDA application were the most important factors affecting the biomass and Cd contents. Third, the highest amount of Cd extracted was 22.18g·hm at 1200 kg·hm GLDA applied 4 times and 10μmol·L DA-6, which was 1.93 times higher than CK (wherein no DA-6 and GLDA were applied) and 1.23 times higher than 10D0 (in which only DA-6 was applied). Finally, the lowest soil total Cd was 0.529mg·kg at 2400 kg·hm GLDA applied 2 times and 10 μmol·L DA-6, which was 21.04% lower than CK and 18.23% lower than 10D0. Therefore, the combination of DA-6 and GLDA can further strengthen the recovery of Cd contaminated farmlands via L..