Abstract:
The remediation of cadmium (Cd)-contaminated soil has gained much attention recently because Cd in soil threatens human health through the food chain. Although tremendous progress has been made in the remediation of Cd-contaminated soil in rice acid soil system, the mechanism and effects of Cd-contaminated soil remediation under these amendments in wheat weak alkaline soil are still limited. In this study, the remediation effect and related mechanism of Cd in weakly alkaline soil were carried out using zeolite, diatomite, and sodium bentonite as the main remediation components, supplemented by calcium dihydrogen phosphate and fulvic acid. The results of field experiments showed that the concentration of Cd reduced by 27.3 ~ 31.2% in rhizosphere soil and 34.3 ~ 54.2% in non-rhizosphere soil, and the maximum reduction rate of Cd concentration in wheat grain was 25.5%. The main factors affecting the concentration of Cd in wheat grains include the change in exchangeable Cd, the absorption capacity of wheat root, and the inhibitory effect on Cd transport from stem to grain in this paper. In general, this work provides a new potential management feasible pathway to alleviate the Cd toxicity of weakly alkaline soil and wheat grain.
摘要:
由于土壤中的Cd通过食物链威胁人类健康,因此镉(Cd)污染土壤的修复方法近年来备受关注。尽管水稻酸性土壤系统中Cd污染土壤的修复取得了巨大的进展,在小麦弱碱性土壤中,这些改良剂对Cd污染土壤修复的机理和效果仍然有限。在这项研究中,利用沸石对弱碱性土壤中Cd的修复效果及相关机理进行了研究,硅藻土,以钠膨润土为主要修复成分,补充磷酸二氢钙和富里酸。田间试验结果表明,根际土壤中Cd的浓度降低了27.3〜31.2%,非根际土壤中Cd的浓度降低了34.3〜54.2%。小麦籽粒中Cd浓度的最大降低率为25.5%。影响小麦籽粒中Cd浓度的主要因素包括交换态Cd的变化,小麦根系的吸收能力,以及对Cd从茎到籽粒运输的抑制作用。总的来说,本研究为缓解弱碱性土壤和小麦籽粒的Cd毒性提供了一条潜在的可行管理途径。