Xiong Shi-juan, Xu Wei-hong, Xie Wen-wen, Chen Rong, Chen Yong-qin, Chi Sun-lin, Chen Xu- gen, Zhang Jin-zhong, Xiong Zhi-ting, Wang Zheng-yin, Xie De-ti
Huan Jing Ke Xue. 2015 Dec;36(12):4630-41.
Incubation experiments were carried out to investigate the influence of different nano zeolite (NZ) and ordinary zeolite (OZ) levels(0, 5, 10 and 20 g · kg⁻¹) on the change trends in fraction distribution coefficient (FDC) of Cd when exposed to different Cadmium (Cd) levels (1, 5, 10 and 15 mg · kg⁻¹), and pot experiments were carried out to investigate their influence on soil Cd fraction and Cd uptake by cabbage. The results in incubation experiments showed that the application of nano zeolite as well as ordinary zeolite effectively decreased the FDC of exchangeable Cd and increased the FDC of Fe-Mn oxide fraction. The FDC of soil Cd from 0 d to 28 d was deceased at first, then increased and tended to be stable, and finally increased. At the end of incubation, the FDC of soil exchangeable Cd decreased from 72.0%-88.0% to 30.0%-66.4%. Exchangeable fraction Cd was the most dominant Cd fraction in soil during the whole incubation. The results in pot experiment indicated that the application of nano zeolite and ordinary zeolite decreased the concentration and FDC of soil exchangeable Cd, and concurrently the concentration and FDC of Cd in carbonate, Fe-Mn oxide, organic matter and residual fraction were increased. The lowest EX-Cd was observed in the treatment with high dose of nano zeolite (20 g · kg⁻¹). The FDC of exchangeable Cd showed significant negative relationship with the soil pH (P < 0.05), and was concurrently extremely positively correlated with Cd concentration in shoot and root of cabbage (P < 0.01). Soil pH increased by 1.8%-45.5% and 6.1%-54.3% in the presence of zeolite when exposed to 5 mg · kg⁻¹ 1 and Cd, respectively; FDC of exchangeable Cd decreased by 16.3%-47.7% and 16.2%-46.7%; Cd concentration in each tissues of cabbage decreased by 1.0%-75.0% and 3.8%-53.2%, respectively. Moreover, the reduction effect of nano zeolite on soil and plant Cd was better than that of ordinary zeolite. The growth of cabbage was stimulated by low and medium zeolite doses (≤ 10 g · kg⁻¹), while inhibited by high zeolite doses (20 g · kg⁻¹). Compared to ordinary zeolite, the biomass of Chinese cabbage was significantly increased by Nano zeolite, while the exchangeable Cd in soil as well as Cd concentration and Cd accumulation of cabbage were significantly reduced.
开展了培养试验，以研究不同纳米沸石（NZ）和普通沸石（OZ）水平（0、5、10和20 g·kg⁻¹）对暴露于不同镉（Cd）水平（1、5、10和15 mg·kg⁻¹）时Cd的分配系数（FDC）变化趋势的影响，并开展了盆栽试验，以研究它们对土壤Cd形态及白菜对Cd吸收的影响。培养试验结果表明，施用纳米沸石和普通沸石均能有效降低交换态Cd的FDC，并提高铁锰氧化物态的FDC。土壤Cd的FDC在0 d至28 d期间先降低，然后升高并趋于稳定，最后又升高。培养结束时，土壤交换态Cd的FDC从72.0%-88.0%降至30.0%-66.4%。在整个培养过程中，交换态Cd是土壤中最主要的Cd形态。盆栽试验结果表明，施用纳米沸石和普通沸石降低了土壤交换态Cd的浓度和FDC，同时提高了碳酸盐态、铁锰氧化物态、有机质态和残渣态Cd的浓度和FDC。在高剂量纳米沸石（20 g·kg⁻¹）处理中，可交换态Cd含量最低。交换态Cd的FDC与土壤pH呈显著负相关（P<0.05），同时与白菜地上部和根部的Cd浓度呈极显著正相关（P<0.01）。当暴露于5 mg·kg⁻¹ Cd时，添加沸石后土壤pH分别升高了1.8%-45.5%和6.1%-54.3%；交换态Cd的FDC分别降低了16.3%-47.7%和16.2%-46.7%；白菜各组织中的Cd浓度分别降低了1.0%-75.0%和3.8%-53.2%。此外，纳米沸石对土壤和植物Cd的降低效果优于普通沸石。低剂量和中剂量沸石（≤10 g·kg⁻¹）促进了白菜生长，而高剂量沸石（20 g·kg⁻¹）则抑制了白菜生长。与普通沸石相比，纳米沸石显著提高了白菜生物量，同时显著降低了土壤中的交换态Cd以及白菜中的Cd浓度和Cd积累量。
