Research On The Differences Of Soil Microbial Community Structure Under Different Vegetation Restoration In Reclaimed Land Of Pingshuo Opencast Mine

As the sensitive indicators of environmental change in restoring habitat,soil microorganisms participate in the material circulation and energy flow of ecological systems,and its community structure and diversity can reflect the reclaimed soil quality and effects of vegetation restoration to some extent.Taking the reclaimed soil in Pingshuo opencast mine as the research object,we select seven plots reclaimed for forests and grass including SIII(locust×ailanthus×elm),SIV(locust×pine),SV(locust forest),SCM(caraganamicrophylla×locust×sea-buckthorn),WUH(sea-buckthorn×elm),WH(sea-buckthorn forest),WG(grass)and also select reclaimed plowland IC1&IC2 respectively two years and seven years,using the no reclaimed plot called UR as the positive control and the orginal land OP & OZ as the negative control.In the series of experiments,the technology Miseq is used to research the bacteria community composition and structure differences.We also have an analysis on the factors which influence the soil bacteria diversity and community structure and compare the reclamation effects on the basis of the community structure.The main findings are as follows:(1)1,183,907 effective bacteria sequences from 36 samples(12 plots)were classified as 4,499 OTUs,belonged to 39 phylum,101 classes,190 orders,349 families,603 genuses and 1,285 species;(2)Reclamation years have an obvious effect on the soil bacteria community diversity and abundance at the beginning of reclamation,while there is no significant difference in the reclaimed plots for many years,meanwhile the soil pH and total phosphorus are also the important influence factors;(3)There is a relatively similar composition of bacteria community in the phyla,class,family and genus level,while the difference of relative abundance is large.Compared to restored forests,the relative abundance of Acidobacteria,Chloroflexi,Planctomycetes in plowland including UR,IC1 and IC2 is lower and the Firmicutes is higher;restoration grassland WG compared with plowland IC2 in 2008,the relative abundance of Actinobacteria and Chloroflexi is higher while the Firmicute and Bacteroidetes is lower;Bacillus,Lactococcus,Nocardioides and Pseudomonas are dominant bacteria genus.(4)RDA and Pearson correlation analysis reveal that the first bacteria communities including Acidobacteria,Chloroflexi,Planctomycetes,Gemmatimonadetes and Nitrospirae have significantly negative correlativity with the second communities including Firmicutes,Verrucomicrobia and Bacteroidetes,while within the group they have the positive correlativity with each other;(5)PCoA,Heatmap and clustering tree of samples show that the soil bacteria communities of all plots can be classified into four groups:(UR?IC1)(IC2)(SV?WUH?WG?SCM)(SIII?SIV?WH?OP?OZ).The soil bacteria communities of locust×ailanthus×elm,locust×pine and sea-buckthorn forest are similar to the original land;the reclamation years than tree species have a more impact on the soil bacteria communities;restoration tree species play a vital role in the reclaimed plots for many years;the dominant bacteria communities have a significant correlativity with the soil pH and available phosphorus.