植物生态学报 ›› 2009, Vol. 33 ›› Issue (4): 629-637.DOI: 10.3773/j.issn.1005-264x.2009.04.001

• 研究论文 •    下一篇

五节芒定居对尾矿砂重金属形态、微生物群落功能及多样性的影响

张崇邦(), 王江, 柯世省, 金则新   

  1. 浙江省台州学院生命科学学院,浙江临海 317000
  • 收稿日期:2008-09-01 修回日期:2009-01-13 出版日期:2009-09-01 发布日期:2009-07-30
  • 通讯作者: 张崇邦
  • 作者简介:*(llhzcb@163.com)
  • 基金资助:
    浙江省自然科学基金(Y507053);台州学院精品成果后续资助基金(2008-151)

EFFECTS OF NATURAL INHABITATION BY MISCANTHUS FLORIDULUS ON HEAVY METAL SPECIATIONS AND FUNCTION AND DIVERSITY OF MICROBIAL COMMUNITY IN MINE TAILING SAND

ZHANG Chong-Bang(), WANG Jiang, KE Shi-Xing, JIN Ze-Xin   

  1. School of Life Sciences, Taizhou University, Linhai, Zhejiang 317000, China
  • Received:2008-09-01 Revised:2009-01-13 Online:2009-09-01 Published:2009-07-30
  • Contact: ZHANG Chong-Bang

摘要:

选择尾矿砂裸地和4个五节芒(Miscanthus floridulus)定居地(RI、RII、RIII和RIV)为样地, 分别研究了五节芒定居对尾矿砂重金属形态转化和微生物功能参数的影响。结果表明: 五节芒自然定居显著地提高了尾矿砂碳酸盐结合态和硫化物-有机物结合态重金属比例(p<0.05), 降低了尾矿砂残渣态重金属的比例(p<0.05)。土壤微生物群落的纤维素分解作用、酚转化作用、固氮作用、氨化作用、硝化作用、有机磷转化作用、功能多样性、4类不同碳源(碳水化合(CH)、聚合物(PL)、胺类化合物(AM)和杂合物(ML))均随着五节芒自然定居显著提高(p<0.05)。而氨基酸(AA)的利用强度却显著下降(p<0.05)。典范相关分析(CCA)表明: 土壤微生物功能参数的总体变化与土壤碳酸盐结合态和硫化物-有机物结合态重金属的含量呈显著正相关, 与残渣态重金属含量呈显著负相关。该研究结果表明, 五节芒定居不仅促进了尾矿砂重金属朝着沉淀态和螯合态方面转化, 而且还显著地改善了尾矿砂微生物群落的功能发挥。因而, 五节芒在重金属矿业废弃地恢复实践中具有较大的应用潜力。

关键词: 五节芒, 尾矿砂, 重金属形态, 微生物群落功能及其多样性

Abstract:

Aims Our objectives are to 1) evaluate the transformation of heavy metal speciations, the mineralization of soil microbial community and diversity of soil microbial community along an inhabitation gradient of Miscanthus floridulus and 2) test relationships between heavy metal speciations and microbial parameters during natural inhabitation by M. floridulus. This is the first step towards large scale application of M. floridulus to the revegetation of mine tailings.
Methods On the basis of the cover of M. floridulus, four levels of inhabitation were selected, along with one bare site for comparison. Three sample plots were randomly placed in each of the five sites, and rhizosphere soil samples were collected from five randomly selected plants in each plot. Heavy metal speciations were analyzed using Tessier’s sequent extraction techniques plus ICP-OES apparatus. Mineralization of the microbial community was determined using soil-culturing methods, and diversity of the microbial community was tested using BIOLOG-Ecoplate.
Important findings Natural inhabitation by M. floridulus significantly increased ratios of individual heavy metal content bound to carbonates and sulfide-organic matter to total corresponding heavy metal content (p<0.05), but decreased the heavy metal ratios bound to residual fraction (p<0.05). Cellulose decomposition, phenol transformation, nitrogen fixation, ammonification, nitrification, organic phosphorus decomposition, functional diversity of the soil community and utilization by the soil microbial community of four carbon substrate groups (carbohydrates, polymers, amines/amides and miscellaneous) significantly increased with inhabitation by M. floridulus (p<0.05), but the utilization of amino acids significantly decreased (p<0.05). Canonical correlation analysis showed that the aggregated changes in microbial functional parameters were significantly and positively related to the heavy metal ratios bound to carbonates and sulfides-organic matter, but were significantly and negatively related to the heavy metal ratios bound to residuals fractions. Our results indicated that natural inhabitation by M. floridulus not only promoted transformation of heavy metals in the mine tailing sand to precipitated and chelated speciation, but also significantly improved functioning of the microbial community. Therefore, M. floridulus exhibited potential for the revegetation of abandoned mining lands contaminated with heavy metals.

Key words: Miscanthus floridulus, mine tailing sand, heavy metal speciations, function and diversity of microbial community