静态浸泡作用下桉树单宁对土壤砷迁移转化影响  

Effects of eucalyptus tannins on arsenic transfer and transformation in soil under static soaking

作　　者：赵婷 宋书巧 曾海琪 ZHAO Ting;SONG Shuqiao;ZENG Haiqi(School of Geographic Science and Planning,Nanning Normal University,Nanning 530000;School of Environment and Life Sciences,Nanning Normal University,Nanning 530000)

机构地区：[1]南宁师范大学地理科学与规划学院,南宁530000 [2]南宁师范大学环境与生命科学学院,南宁530000

出　　处：《环境保护科学》2025年第2期34-43,共10页Environmental Protection Science

基　　金：国家自然科学基金青年项目(42301073);广西科技基地和人才专项(桂科AD22080023)。

摘　　要：为研究桉树单宁对土壤砷迁移转化的影响,以广西河池矿区砷污染土为研究对象,添加不同量砷污染土壤与桉树凋落叶浸提液的固液比为1∶5和1∶10和不同浓度0、12.5、25、50和100 mg/mL的桉树凋落叶浸提液进行静态浸泡试验,分析22 d浸泡过程中土壤及浸出液pH、电导率、单宁和土壤砷赋存形态转化及迁移特征。结果表明:随着浸提液浓度和浸泡时间增加,固液比1∶10较1∶5条件下土壤pH显著降低,电导率和单宁含量显著增加。相关性分析显示,土壤单宁与水溶态砷呈现显著正相关关系,与弱酸提取态、还原态以及残渣态砷呈现显著负相关关系;促进还原态和残渣态砷向水溶态、弱酸提取态转化,并提高砷的浸出速率。To study the influence of eucalyptus tannins on the migration and transformation of arsenic in soil,the arsenic-contaminated soil from a mining area in Hechi,Guangxi was taken as the research object.Static soaking experiments were carried out by adding different amounts of arsenic-contaminated soil and eucalyptus leaf litter extracts with solid-to-liquid ratios of 1:5 and 1:10 and different concentrations of 0,12.5,25,50,and 100 mg/mL.The pH,electrical conductivity,tannin content of the soil and leachate,as well as the transformation and migration characteristics of the occurrence forms of arsenic in the soil during the 22-day soaking process were analyzed.The results showed that with the increase of the extract concentration and soaking time,the soil pH was significantly reduced under the solid-to-liquid ratio of 1:10 compared with that of 1:5,while the electrical conductivity and tannin content were significantly increased.Correlation analysis indicated that there was a significant positive correlation between soil tannin and water-soluble arsenic,and significant negative correlations between soil tannin and arsenic in weakly acid-extractable,reducible,and residual forms.It was also found that eucalyptus tannins promoted the transformation of reducible and residual arsenic into water-soluble and weakly acid-extractable forms and increased the leaching rate of arsenic.

关 键 词：静态浸泡 桉树凋落叶浸提液 桉树单宁 砷赋存形态 迁移转化 

分 类 号：X58[环境科学与工程—环境工程]