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中国农学通报

中国农学通报 ›› 2014, Vol. 30 ›› Issue (2): 233-239.doi: 10.11924/j.issn.1000-6850.2012-3997

所属专题： 土壤重金属污染

• 资源 环境 生态 土壤 气象 • 上一篇    下一篇

生物质炭修复后污染土壤铅赋存形态的转化及其季节特征

崔立强 杨亚鸽 严金龙 丁成   

  • 收稿日期:2012-12-11 修回日期:2013-01-10 出版日期:2014-01-15 发布日期:2014-01-15
  • 基金资助:
    江苏省 “六大人才高峰项目(2011年农业领域)”； 盐城工学院人才引进项目 “稻田土壤重金属污染的生物炭修复机制” (kjc2012022)。

Speciation and Season Change Characteristic of Lead in Contaminated Soil with Biochar Amendment

  • Received:2012-12-11 Revised:2013-01-10 Online:2014-01-15 Published:2014-01-15

摘要： 为了解农田土壤污染典型重金属铅的赋存形态对生物质炭修复措施的响应，以不同生物质炭施用量修复铅污染土壤为研究对象，采用BCR三步连续提取法对2010—2012年土壤中铅的形态分布特征及其季节变化规律进行分析，探讨铅污染稻田生物质炭修复的稳定机制。结果表明：生物质炭施用后，土壤pH和有机质(SOM)分别升高了0.11~0.65个单位和16.0%~51.2%。土壤中铅元素赋存形态中，酸溶态、还原态和氧化态组分显著降低并向残渣态转化，譬如2010年小麦季，施用生物质炭后，三者分别降低了5.3%~25.0%、9.8%~22.3%和40.8%~43.5%；而残渣态铅含量升高了7.8%~16.1%，但小麦季及水稻季的响应有所差异，4个形态的各个处理2011年小麦季显著高于2010年水稻季9.1%~28%，原因在于不同水分条件导致氧化还原电位的变化。铅的各赋存形态与土壤pH及SOM值具有较好的相关性，生物质炭本身含有的大量碱性物质及羟基、羧基等有机官能团可通过络合、沉淀等化学机制有效实现土壤中铅的固定，说明生物质炭的施用可有效降低铅元素的生物可利用性和生态毒性，为重金属土壤污染的修复研究提供理论依据。

关键词: 菌落形态, 菌落形态

Abstract: In order to study the chemical speciation of typical heavy metal lead in contaminated farmland soil and the response to the amendment by biochar, the BCR three-step sequential extraction was used to the speciation analysis of lead in contaminated soils amended biochar with different application rate during three years (2009-2012), the seasonal variations and stability mechanism was also discussed. Results showed that the pH value and the content of soil organic carbon (SOM) increased by 0.11-0.65 units and 16.0%-51.2%, respectively. Acid dissolved state, reduced state and oxidation state components were significantly reduced and translated to residue state, for example, the three of them decreased by 5.3%-25.0%, 9.8%-22.3% and 40.8%-43.5% in wheat season in 2010, and the residual state increased by 7.8%-16.1%, but different responses in wheat and rice season were also found that the four states concentration were higher in wheat season (2011) than rice season (2010) for the different oxidation-reduction potential due to the different water conditions. The different lead states were significant correlation with soil pH and SOM. Biochar contained large amounts of alkaline material and hydroxyl, carboxyl and organic functional groups, which could fix the varieties, lead effectively by complexation, precipitation, and other chemical mechanisms. It showed that remediation of soils by biochar could effectively reduce the bioavailability and ecotoxicity of lead, and provided a theoretical basis for the amendment of soil polluted by heavy metals.