Study On Diversity Of Soil Bacteria In Mining Areas And Isolation,Identification And Application Of Dominant Strain

Microbial diversity in soil mainly refers to the differences among races,regions and biota in soil microbial communities.It is of great significance in determining and protecting soil quality,ecosystem stability and other aspects.Its adaptability and buffering effect against the deterioration of soil microecological environment were greatly enhanced.The study of microbial diversity in soil is important for developing an unconventional microbial resource,responding to climate change worldwide,controlling environmental pollution,maintaining the function of ecological service mechanisms,and promoting sustainable use of soil.In this study,two sampling points were selected according to the growth state of plants in the mining area,named A zone and B zone,each sampling area adopts five,and respectively choose top soil(0-3 cm),plant rhizosphere(20-23 cm)and deep soil(40-43 cm),They were named A1,A2,A3,and B1,B2,and B3.In this study,by analyzing the physical and chemical properties of the mine soil and carrying out high-throughput determination and analysis of the microorganisms in the soil,the difference of bacterial colonies was determined,and the dominant bacterial communities were screened and identified.The obtained strain was made into bacterial fertilizer,and its effect was determined by plant planting test in the experimental field.The research results are as follows:(1)Analysis of soil microbial diversityThrough the analysis of soil physical and chemical properties,the results showed that the contents of available potassium,available phosphorus and hydrolytic nitrogen in soil samples were different,and the overall performance was that the three physical and chemical properties of soil in A region were higher than that in B region.The soil in both regions is alkaline on the whole.Alpha diversity,genus classification,diversity of flora abundance and community gene function were also analyzed and compared.The results showed that there was little difference in the diversity of the community,but there was a great difference in the abundance of the flora between the two regions.The community of acidobacter,blastomonas and bacteroidetes in area A was determined as the dominant bacteria.(2)Isolation and screening of dominant bacterial strains in mine soilTwo relatively dominant strains were isolated from the mine soil by the organic combination of enrichment culture and separation and screening.The 16 S r DNA PCR was extended and sent for sequencing.The sequencing results and data were compared and analyzed by BLAST for systematic analysis.The results showed that the optimum growth temperature of NEW-1 was 30?,and the optimum growth temperature of NEW-2 was 37?,and the optimum p H of both strains was 8.(3)Preparation of bacterial fertilizer and field planting experimentThe bacterial fertilizer was prepared by solid compost fermentation,and five groups were set,which were A(blank),B(single New-1 bacterial fertilizer),C(single New-1bacterial fertilizer),D(mixed New-1 and New-2 bacterial fertilizer),and E(mixed YZ-1,New-1 and New-2 bacterial fertilizer).After planting,the vegetable growth was observed and the soil physical and chemical properties were analyzed.The results of transverse comparison showed that multiple mixed bacterial fertilizers could promote plant growth and improve soil fertility.