纳米钢渣硅钙肥对重金属复合污染酸性水稻土的修复机制与生态评估

项目名称： 纳米钢渣硅钙肥对重金属复合污染酸性水稻土的修复机制与生态评估

项目编号： No.51509249

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 水利工程

项目作者： 宁东峰

作者单位： 中国农业科学院农田灌溉研究所

项目金额： 20万元

中文摘要： 钢渣富含硅钙等氧化物，是低廉的硅钙肥原料和酸性土壤重金属钝化剂。但是钢渣中氧化物在土壤中释放缓慢，利用效率低。本项目针对钢渣农用存在的弊端，结合纳米颗粒的优势，拟筛选出纳米钢渣硅钙肥的适宜制备技术，并对其形貌结构、比表面积和元素组成进行表征。继而通过序批培养试验，探明纳米钢渣硅钙肥对水体中Cu2+、Cd2+和Zn2+的吸附特性和影响因素；进一步通过水稻盆栽试验，探讨纳米钢渣硅钙肥对重金属污染酸性水稻土的修复技术，利用X射线衍射（XRD）、扫描电镜/能谱仪（SEM /EDS）等仪器揭示钢渣中CaO、SiO2对土壤和根际土壤以及植物体内重金属形态变化的作用机理；借助酶标仪、聚合酶链反应-末端限制性片段长度多态性技术 (PCR-TRFLP) 揭示钢渣硅钙肥施用后对土壤酶活性和微生物群落结构的影响。最后，对纳米钢渣硅钙肥施用后在第二季的余效和对重金属的稳固性进行跟踪监测。

中文关键词： 纳米钢渣；酸性水稻土；重金属；钝化修复；微生物

英文摘要： With the rapid development of industry and agriculture, heavy metal contamination in acidic paddy soil is becoming more and more urgent problem in China. Steel slag is byproducts of steel and iron industries, containing large amounts of CaO and SiO2. It has been well documented that steel slag is a low-cost material of silicon-calcium fertilizer and acid soil amendment. However, The release speed of CaO and SiO2 from slag is very slow, which significantly impact the utilization efficiency of slag. In consideration of this problem and the advantages of nano-particles, we propose to produce nano-slag-based silicon fertilizer. In this work, firstly, we will choose one or two better methods to make nano-particles of slag, then analyze the morphology structure, elemental composition, and specific surface area of nano-slag. Secondly, we will study the adsorption characteristics of Cu2+, Cd2+ and Zn2+ by nano-slag and the main impact factors through Batch incubation experiments. Thirdly, we will investigate the immobilization efficiency of nano-slag in a multi-metal contaminated soil through rice pot experiments, using X-ray diffraction (XRD), scanning electron microscopy/energy spectrometer (SEM/EDS) to demonstrate the effects and mechanisms of CaO and SiO2 in slag on heavy metals contents and distributions in soil , rhizosphere soil and plant, as well as using multiscan spectrum and Polymerase Chain Reaction-Terminal Restriction Fragment Length Polymorphism (PCR-TRFLP) techniques to discuss the effects on enzymatic activity and microbial community structure in soil and rhizosphere soil. Lastly, we will test the residual effects of slag and stability of heavy metals in the late rice.

英文关键词： Nano-slag;Acidic paddy soil;Heavy metal; Immobilization;Microorganism