| Ionic liquids (ILs) are organic salts consisting entirely of ions and exist as liquids at room temperature. Ionic liquids as a new generation of chemical solvent, because of its environmentally friendly features, has been a wide range of applications in many fields of chemistry, is considered to be a good substitute for traditional solvent, there is a huge potential values. Original research reports is thought to belong to the environmental friendly chemical solvent, ionic liquid, however, in recent years, as the researchers for the use of ionic liquids may be the effects on the entire ecological communities of risk assessment, ionic liquid green sex concept has been widely questioned. The change of soil microbial community structure and diversity can reflect the change of soil environmental quality in earlier process, and reveal the ecological function difference, microorganism is considered to be one of the evaluations of soil environmental quality is healthy or not sensitive biological indicator, the change in a certain extent, reflects the soil quality and environment safety.This study chose the same length of carbon chain of two typical imidazoles ionic liquid [Csmim] C1 and [Csmim] Br, with brown soil as the mechanism of soil, using the dilute plate method and enzyme activity photometry method and Biolog-ECO plate, T-RFLP and RT-PCR technique, studied the ionic liquid canister to 7,14,21 and 28 days, the soil bacteria, fungi, actinomycetes, such as the number of culturable microorganisms, urease, phosphatase, such as soil enzyme activity, microbial metabolism function diversity, microbial community structure and function of soil microbial diversity of AOA and AOB community quantity change.The results of the study are as follows:(1) [C8mim]Cl in the treatment of early and late inhibit bacteria, in the middle of the process to promote bacterial growth. [C8mim]Br on the number of culturable bacteria in the soil in the whole canister to cycle a significant dose-effect. High concentration [C8mim]Br and [C8mim]Cl treatment on the number of fungi in the soil in the whole canister to cycle a significant dose-effect inhibition; Low concentration [C8mim]Br significantly promote the number of fungi in the soil increased. [Csmim]Br and [Csmim]Cl treatment for 21 days and before treatment group of actinomycetes was increased in number,28 days this role almost disappear.(2) With the extension of processing time, the increase of concentration, [Csmim]Cl and [C8mim]Br treatment group showed a significant increase in urease activity. Ionic liquid on soil phosphatase activity in the general no significant influence in the experimental period.(3) [C8mim]Cl on soil microbial metabolic main show is the influence of carbon source, sugars, amino acids, utilization increased, phenols, the utilization ratio of polymer and amine; [Csmim] Br treated microbial carbon source metabolic changes mainly for the utilization of sugars and amino acids and the phenolic compounds and increased the utilization rate of the polymer. That the sugar, acid, amino acids, polymers, phenolic compounds and amine which of these four carbon source as the main metabolic substrate in the changes of microbial community, lead to the change of the microbial community abundance and evenness, it also proves the Simpson index and Shannon and PCA analysis the change rule of spectrums dispersed in reason, and carboxylic acid as the main carbon source of stability of the microbial community.(4) Analysis of ionic liquid [Csmim]Cl and [Csmim]Br in the soil microbial community structure spectra after processing, the maximum fragment length selection area changes in spectra of 66,92,138/139,148,400 and 432, found that their corresponding are for Arthrobacter, Bacteroides, Bacillus, Eubacterium, Rhizobium and Ralstonia.(5) In this test cycle and the concentration range, [Csmim]Cl and [Csmim]Br AOB-amoA gene copy number treatment group were decreased significantly; In this test set within the test time and concentration, [Csmim] Cl treatment group of AOA-amoA gene copy number significantly reduced; [Csmim]Br treatment group in infected 7 and 14 days of AOA-amoA gene copy number decreased significantly,21 and 28 days, part of the treatment group of AOA-amoA gene copy number increased.In conclude, [Csmim]Cl and [Csmim]Br has the same length of carbon chain, the soil ecological effects also showed great similarity, will be different degrees of influence on soil ecological environment. |
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