不同镉水平下纳米沸石对土壤pH、CEC及Cd形态的影响  

Effect of Nano Zeolites on pH,CEC in Soil and Cd Fractions in Plant and Soil at Different Cadmium Levels

作　　者：迟荪琳 徐卫红[1] 熊仕娟 王卫中[1] 秦余丽 赵婉伊[1] 张春来[1] 李彦华[1] 李桃[1] 张进忠[1] 熊治庭[2] 王正银[1] 谢德体[1] 

机构地区：[1]西南大学资源环境学院,重庆400715 [2]武汉大学资源环境学院,武汉430079

出　　处：《环境科学》2017年第4期1654-1666,共13页Environmental Science

基　　金：现代农业产业技术体系建设专项(Nycytx-25);国家自然科学基金项目(20477032);国家科技支撑计划项目(2007BAD87B10)

摘　　要：通过室内培养试验及土培试验研究了不同镉水平(1、5、10和15 mg·kg^(-1))下纳米沸石和普通沸石对土壤pH、CEC及Cd形态的影响.结果表明,室内培养试验中,施用沸石(5、10和20 g·kg^(-1))均显著提高了不同镉(1、5、10和15 mg·kg^(-1))处理中的土壤pH和土壤CEC值,降低了土壤可交换态镉含量,增加了碳酸盐结合态、铁锰氧化态、有机态和残渣态镉含量,以纳米沸石(20 g·kg^(-1))对土壤可交换态镉的降低效果最好.土壤pH、土壤CEC与土壤可交换态镉含量呈极显著负相关(P<0.01),与铁锰氧化态镉含量均呈极显著正相关(P<0.01).土培试验中,在1 mg·kg^(-1)和5 mg·kg^(-1)Cd条件下,施用沸石(5、10和20 g·kg^(-1))使土壤可交换态镉FDC降低了6.4%~63.2%,使大白菜地上部去离子水提取态镉和乙醇提取态镉的分配比例分别降低了2.1%~56%和11.8%~100%,相同沸石使用量下的降低效果以纳米沸石优于普通沸石.在1 mg·kg^(-1)Cd条件下,大白菜地上部镉形态的FDC与土壤CAB-F和OM-F的FDC有显著相关性(P<0.05);在5 mg·kg^(-1)Cd条件下,大白菜地上部镉形态的FDC主要与土壤OM-F和RES-F形态的FDC存在显著相关性(P<0.05).Soil incubation experiment and pot experiment were carried out to investigate the influence of nano zeolite（NZ） and ordinary zeolite（OZ） on the soil pH,cation exchange capacity,concentration of soil Cd,soil Cd fraction and Cd uptake by Chinese cabbage when exposed to different Cd pollution levels（1,5,10 and 15 mg·kg^-1）.The results of soil incubation experiment showed that the nano zeolite and ordinary zeolite dose（5,10 and 20 g·kg^-1） increased the soil pH and cation exchange capacity,and decreased the concentration of soil exchangeable Cd,while increased the concentration of Cd in carbonate,Fe-Mn oxide,organic matter and residual fraction.The lowest EX-Cd was observed in the high nano zeolite（20 g·kg^-1） treatment.The soil pH and cation exchange capacity was extremely negatively correlated with the concentration of soil exchangeable Cd（P〈0.01）,and extremely positively correlated with the concentration of soil Fe-Mn oxide Cd（P〈0.01）.The results of pot experiment showed that the FDC of exchangeable Cd in soil decreased by 6.4%-63.2%,and the FDC of water-extractable and ethnol-extractable Cd in Chinese cabbage decreased by 2.1%-56% and 11.8%^-100% with zeolite application,respectively.Moreover,the reduction effect of nano zeolite on Cd concentration in soil and plant was better than that of ordinary zeolite.The FDC of Cd fraction in shoot of Chinese cabbage showed correlation with the FDC of carbonate Cd and organic matter Cd in soil（P〈0.05） when exposed to 1 mg·kg^-1Cd pollution.Moreover,correlation was also found in the FDC of organic matter Cd and residual Cd in soil（P〈0.05） under 5 mg·kg^-1Cd pollution.

关 键 词：土壤镉污染 纳米沸石 土壤PH 土壤CEC 土壤-植物Cd形态分布 

分 类 号：X53[环境科学与工程—环境工程]