两种外源有机酸对蜈蚣草修复锑污染土壤的影响  

Effects of two exogenous organic acids on the phytoremediation of antimony contaminated soil by Pteris vittata L.

作　　者：姚琴 杨爱江[1,2,3] 牛阿萍 刘吉 邹海洮 朱桓毅 YAO Qin;YANG Aijiang;NIU Aping;LIU Ji;ZHOU Haitao;ZHU Huanyi(Key Laboratory of Karst Georesources and Environment,Ministry of Education,College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025;Field Observation and Research Station of Karst Environment and Ecosystem,Ministry of Education,Guizhou University,Guiyang 550025;Institute of Environmental Engineering Planning and Design,Guizhou University,Guiyang 550025;Guizhou Guida Yuanheng Environmental Protection Technology Co.,LTD.,Guiyang 550025)

机构地区：[1]贵州大学资源与环境工程学院,喀斯特地质资源与环境教育部重点实验室,贵阳550025 [2]贵州大学,喀斯特环境生态系统教育部野外科学观测研究站,贵阳550025 [3]贵州大学环境工程规划设计研究所,贵阳550025 [4]贵州贵达元亨环保科技有限公司,贵阳550025

出　　处：《环境科学学报》2022年第8期405-414,共10页Acta Scientiae Circumstantiae

基　　金：贵州省科技计划项目(No.黔科合基础[2020]1Y195);贵州省教育厅省级重点学科建设项目(No.黔学位合字ZDXK[2016]11);贵州省国内生态学一流学科建设项目(No.GNYL[2017]007)。

摘　　要：以蜈蚣草(Pteris vittata L.)为受试材料,利用盆栽试验研究了不同添加量(0、5、10、20 mmol·kg^(-1))外源柠檬酸和苹果酸对锑(Sb)污染土壤pH和Sb形态的影响,以及两种外源有机酸对蜈蚣草富集Sb和蜈蚣草抗氧化系统的影响,并分析了利用有机酸强化蜈蚣草修复锑污染土壤的可能性及其作用机制.结果表明,土壤锑含量为500 mg·kg^(-1)时,种植20 d后,两种有机酸使土壤pH从6.26降到4.99~5.93,土壤中弱酸提取态Sb含量增加,残渣态Sb含量减小.两种有机酸均提高了蜈蚣草根、茎和叶中Sb含量,且作用效果为柠檬酸>苹果酸;20 mmol·kg^(-1)柠檬酸的加入使根、茎和叶中Sb含量分别达到最大值4740、256、77.5 mg·kg^(-1),较对照组分别提高77.08%、230.90%、84.39%.相比对照组,柠檬酸和苹果酸添加均可显著提高蜈蚣草根系活力和抗氧化酶活性,降低丙二醛(MDA)含量,其中,柠檬酸的作用最大.说明两种有机酸通过提高蜈蚣草对Sb的吸收富集,增强对Sb的耐性来促进锑污染土壤的修复.In order to investigate the mechanism of phytoremediation of antimony(Sb)contaminated soils,Pteris vittata L. was selected as tested plants to research the effect of different concentrations of (0,5,10,20 mmol·kg^(-1))exogenous citric acid and malic acid on soil pH and Sb morphology,as well as Sb accumulation and antioxidant system of Pteris vittata L..The results indicated that two organic acids can reduced the pH of soil containing500 mg·kg^(-1)Sb from 6.26 to 4.99~5.93,increase the contents of Sb extracted by weak acid and decrease the contents of residual Sb in soils after 20 d planting time for Pteris vittata L..Both organic acids can increase Sb concentrations in the roots,stems and leaves of Pteris vittata L.,with the trend:citric acid > malic acid;Sb concentrations in roots,stems and leaves reach the maximum value of 4740,256,77.5 mg·kg^(-1)when 20 mmol·kg^(-1)citric acid was added,which were 77.08%,230.90%,84.39% higher than the control group. Compared with the control group,the addition of citric acid and malic acid significantly improved the root activity and antioxidant enzyme activity of Pteris vittata L.,and reduced the MDA content,in both of which the effect of citric acid is stronger. Overall,the two exogenous organic acids can promote the restoration of Sb-contaminated soils by increasing the absorption and enrichment of Pteris vittata L. for Sb,and enhancing the tolerance of Pteris vittata L. for Sb.

关 键 词：外源有机酸 柠檬酸 苹果酸 锑污染土壤 蜈蚣草 植物修复 

分 类 号：X53[环境科学与工程—环境工程]