针对焦化厂等土壤中铬(Cr)、砷(As)重(类)金属和菲(Phe)、苯并[a]芘(BaP)等多环芳烃(PAHs)风险高、绿色低碳修复技术缺乏等突出问题,以黑麦草-玉米-食醚红球菌(Rhodococcusaetherivorans,BW2)开展植物微生物联合。结果表明,63d后植物微生物联合修复组土壤中Cr、As、Phe和BaP浓度分别下降9.63%、5.28%、45.14%和26.87%,其中重金属的去除主要依赖于植物作用,而PAHs去除则在很大程度上取决于微生物与植物的共同作用;植物主要吸收可提取态重金属,63d后不同修复组土壤中可交换态Cr平均下降2.19%,而As则由于降解作用使修复过程中可交换态有所增加;可交换态Cr和碳酸盐结合态Cr与土壤中放线菌门为强正相关,2种形态As则与拟杆菌门、装甲菌门、FBP菌门和浮霉菌门呈正相关。污染物去除效率之间存在明显相互作用,同时受酶活性和不同功能微生物丰度的动态影响,反之土壤微生物群落结构和功能也在土壤污染物种类、浓度及理化性质等综合作用下发生改变。

In view of the prominent problems of chromium (Cr), arsenic (As) heavy (class) metals and polycyclic aromatic hydrocarbons(PAHs) such as phenanthrene (Phe) and Benzo[a]pyrene (BaP) in soils such as coking plants, and the lack of green and low-carbonremediation technologies, rye grass-maize-Rhodococcus aetherivorans (BW2) was utilized for plant-microbe co-remediation. The resultsshow that Cr, As, Phe, and BaP concentrations in the soil of the combined remediation group decrease by 9.63%, 5.28%, 45.14%, and26.87%, where the removal of heavy metals is largely dependent on plants, the removal of PAHs is largely dependent on microorganismsand their interactions with plants. Plants mainly absorb extractable heavy metals, and the exchangeable Cr in soil of different restoration groups decreases by 2.19% on average after 63 d, while the exchangeable As increases during the restoration process due to degradation. The exchangeable Cr and carbonate-bound Cr are strongly positively correlated with actinomycetes in soil, while the two As forms arepositively correlated with Bacteroidetes, Armatimonadetes, FBP and Planctomycetes. There is an obvious interaction between pollutant removal efficiency, and it is also affected by the dynamic abundance of enzyme activities and different functional microorganisms. In turn,soil microbial community structure and function also change under the comprehensive effect of soil pollutant types, concentrations andphysical and chemical properties.

0 引言

1 试验

   1.1 材料与仪器

   1.2 研究方法

2 结果与讨论

   2.1 植物生长特性

   2.2 土壤中重金属形态变化

   2.3 土壤中菲和苯并［a］芘的修复效率

   2.4 污染土壤修复过程中生物学特性变化

   2.5 重金属-PAHs复合污染土壤植物微生物联合修复机理

3 结论