生物质灰分对土壤重金属迁移和转化的影响研究  

Effects of Biomass Ash on the Transformation and Migration of Heavy Metals in Soil

作　　者：刘艳艳[1] 周秉玮 向何锋 叶晓春[1] 袁必和 张海玲 LIU Yanyan;ZHOU Bingwei;XIANG Hefeng;YE Xiaochun;YUAN Bihe;ZHANG Hailing(School of Safety Science and Emergency Management,Wuhan University of Technology,Wuhan 430070,China.;不详)

机构地区：[1]武汉理工大学安全科学与应急管理学院,湖北武汉430070 [2]中国工程物理研究所材料研究所,四川绵阳621900

出　　处：《武汉理工大学学报（信息与管理工程版）》2023年第1期41-48,共8页Journal of Wuhan University of Technology：Information & Management Engineering

基　　金：湖北省重点研发计划项目(2021BCA216).

摘　　要：森林火灾不仅使得土壤表面残留大量灰分,还导致土壤物化性质变化,其对土壤中重金属迁移和转化的影响至关重要。通过模拟野火燃烧生物质制备灰分,将不同比例(0%、1%、5%、10%)的灰分与污染土样混匀进行土壤培养试验,探究灰分比例对土壤理化性质和重金属迁移、转化的影响;通过土柱淋溶试验模拟不同pH(3.8、4.7、5.6)降雨条件下土壤重金属的释放特征。土壤培养表明:灰分的引入显著提高土壤pH、阳离子交换量和有机质含量,且随着灰分投加比例越大,效果越明显;生物质灰分能显著降低土壤中重金属有效态的比例,降低重金属的迁移能力;随着灰分投加比例的增加,重金属固定率不断增加;各重金属固定率的顺序为Pb>Zn>Cu>Cd。淋溶试验表明:淋溶前期,燃烧土壤淋出液中重金属浓度普遍高于未燃烧土壤(Cd除外),分别可增加7.43~24.34 mg/L(Zn)、0.89~1.69 mg/L(Cu)、0.102~0.141 mg/L(Pb);淋溶中后期燃烧土壤的淋出液中重金属浓度则低于未燃烧土壤,说明生物质灰分对土壤中重金属的释放起到一定缓冲和固定作用。Forest fire not only leaves a large amount of biomass ash on the soil surface,but also leads to changes in the physical and chemical properties of soil,which plays an important role in the migration and transformation of heavy metals in soil.In this study,biomass ash was prepared by simulating combustion,and different proportions of ash(0%,1%,5%,10%)were mixed with contaminated soil for soil culture experiments to explore the effects of ash proportion on soil physical and chemical properties and heavy metal migration/transformation.Soil leaching experiment was used to simulate the release characteristics of heavy metals in soil under different pH(3.8,4.7,5.6)rainfall conditions.Soil culture results showed that the addition of ash significantly increased soil pH,cation exchange capacity and organic matter content,and the effect was more obvious with the increase of adding proportion;In addition,biomass ash can significantly reduce the proportion of available heavy metals in soil,and reduce the migration capacity of heavy metals.The fixation rate of heavy metals increased with the increase of ash content.The order of fixation rate of heavy metals was Pb>Zn>Cu>Cd.Leaching experiments showed that the concentration of heavy metals in burned soil was higher than that in unburned soil(except Cd)at the early stage of leaching,which increased by 7.43~24.34 mg/L(Zn),0.89~1.69 mg/L(Cu)and 0.102~0.141 mg/L(Pb),respectively.However,the concentration of heavy metals in the leachate of the burned soil was lower than that of the unburned soil,indicating that the biomass ash content had a certain buffering and fixing effect on the release of heavy metals in the soil.

关 键 词：生物质灰分 森林火灾 重金属释放 迁移转化 土壤污染 

分 类 号：X53[环境科学与工程—环境工程]