Study On The Effect Of Restore Vegetation Components On Weathering Function Microorganisms Of Coal Gangue Yard

The coal mines in Longli Baixing town,Guizhou Provence are mainly enriched in the Dumu River Basin,and a large amount of coal gangue is produced during the coal mining process,causing serious pollution to the ecological environment of the mining area.Phytoremediation is an effective measure to solve ecological damage and environment pollution in mining area,which is both economical and safe.In recent years,scholars form all over the word have carried out a lot of research on the remediation plants of coal gangue dumps,and obtained a series of research results,but there are few studies on the phytoremediation that affects the original weathering functional microorganisms（Thiobacillus ferrooxidans）.In this study,a weathered coal gangue dump in a phytoremediation in Baixing Town,Longli county,was taken as the research object.In this paper,the high-throuhgput sequencing Miseq technology is used to analyze the function of bactria and variation characteristics of community structure in vegetation restoration coal gangue piles in Guizhou Province.Through the shake flask experiment,the organic acid,amino acid,humic acid and fulvic acid were added to the Thiobacillus ferrooxidans system to explore the effect of the addition of plant rhizosphere components on the biological oxidation of Fe²⁺.The non-targeted metabolomic analysis by LC-MS was carried out using the bacterial liquid after the culture,to explore the effect of the addition of plant components on the metabolite differences and metabolic pathways of Thiobacillus ferrooxidans.In order to provide theoretical support for the effect of phytoremediation on the weathering process of coal gangue piles and the control of pollutant release.The main conclusions of this study are as follows:（1）Samples were collected for thr coal gangue matrix before and after the restoration plants,and the analysis and test result showed that:the p H of the yard was significantly increased,the EC and Eh were reduced,reduce the content of Fe,Mn,Cu,Ni and other substances in the coal gangue leaching solution.The main dominant bacterial phyla in the coal gangue dump are Proteobacteria,Actinobacteria,Chloroflexi,and the maximum abundance in the restored plant substrate can reach44.38%,36.50%and 18.87%.Compared with the coal gangue matrix of unrestored vegetation,restore vegetation had inhibitory effect on Acidothemus bacterial growth.The bacterial community structure was greatly affected by p H,Cu,Fe and Zn.（2）After restored plants,the contents of organic acid,amino acid,humic acid and fulvic acid in the rhizosphere were generally high than those in the gangue matrix of unrestored plants,but the contents were different in the rhizosphere of different plants.The contents of propionic acid and succinic acid were 9.106 mg/kg and 8.684mg/kg,respectively,which were significantly higher than those of other organic acids of Imperata cylindrica Beauv.var.major（Nees）C.E.Hubb.The organic acids with high content in the rhizosphere of Artemisia argyi were acetic（24.796 mg/kg）and propionic acid（22.231 mg/kg）.The organic acids with high content in the rhizosphere of Lolium Perenne and Robinia pseudoacacia was propionic acid;the organic acids with high content in Robinia pseudoacacia rhizosphere were formic acid（19.02mg/kg）and propionic acid（15.355 mg/kg）,respectively.The main amino acids secreted by rhizosphere of Beauv.var.major（Nees）C.E.Hubb.were valine,leucine and tyrosine,respectively.The main amino acids secreted by rhizosphere of Artemisia argyi were phenylalanine,valine,leucine and glutamic,respectively.The main amino acids secreted by rhizosphere of Lolium Perenne and Robinia pseudoacacia was phenylalanine.（3）The addition of organic acid and fulvic acid did not have obvious effect on p H,ORP and EC in Thiobacillus ferrooxidans system.Both the organic acid and amino acid system showed inhibitory effect on the biooxidation of Fe²⁺by Thiobacillus ferrooxidans,and the general expression was succinic acid>citric acid>tartaric acid,glycine≈valine>phenylalanine,when the concentration of amino acid was 100 times,Thiobacillus ferrooxidans lost activity.The inhibitory effect on total iron precipitation was generally expressed as succinic acid>tartaric acid>citric acid,glycine>phenylalanine>valine,and the greater the concentration of amino acid added,the stronger the inhibitory effect on total iron precipitation.The addition of humic acid and fulvic acid generally promoted the biooxidation of Fe²⁺by Thiobacillus ferrooxidans,and the total iron precipitation rate increased from 10.53%to 53.04%as the concentration of humic acid was increased from 0.001 to 10 times.（4）The main metabolic pathways of Thiobacillus ferrooxidans were divided into four categories,include namely metabolism,genetic information processing,environmental information processing and cellular processes.There were significant differences in the metabolites in the system after addition of organic acid,amino acid,humic acid and fulvic acid.In the treatment of tartaric acid addition,25 metabolites with significant differences were screened out.The most significant pathways for metabolite enrichment were purine metabolism,cysteine and methionine metabolism,pyrimidine metabolism,lysine metabolism and carbapenem biosynthesis;9metabolites with significant differences were screened in the glycine treatment group,the most significant pathways for metabolite enrichment are the biosynthesis of secondary metabolites,glyoxylic acid and dicarboxylic acid metabolism;11metabolites with significant differences were screened in the humic acid treatment group,and the most significant metabolite enrichment was The pathways are biosynthesis of various secondary metabolites,glyoxylic acid and dicarboxylic acid metabolism,pyrimidine metabolism,quinone and other terpenoid quinone biosynthesis;only two metabolites with significant differences were screened in the fulvic acid treatment group.With the increase of the addition concentration of each component,the differential expression of metabolites of Thiobacillus ferrooxidans in each system gradually increased,and the differential expression of metabolites of Thiobacillus ferrooxidans in the addition system of the 4th and 5th concentration gradient of fulvic acid maximum.