Effects Of Planting Different Sand-fixing Shrubs In Straw Checkerboard On Surface Soil Microbial Diversity And Community Structure In The Sandy Area Of Eastern Ningxia

Soil microorganisms are an integral part of the ecosystem,which participate in the important ecological processes,and are the drivers of the material circulation and energy conversion.In the plant-soil ecosystem,different plants tend to choose different microbial community composition,which affects the soil microbial community function in a farther step.In order to prevent the damage of wind and sand,a large area of sand-fixation shrubbery has been planted in the northern aeolian sandy area in China.Although a large number of studies have evaluated its impact on soil physical and chemical properties and other aspects,the researches about the impact on the diversity,structure,composition and function of the microbial community are very limited.In this paper,the Baijitan National Nature Reserve,located on the south western edge of the Mu Us Desert,is used as the research area,use Straw checkerboard combining with different sand-fixing shrubs(Caragana korshinskii,Corethrodendron fruticosum var.Mongolicum,Caragana korshinskii mixed with Corethrodendron scoparium,Caragana korshinskii mixed with Calligonum mongonicum,Corethrodendron scoparium mixed with Calligonum mongonicum)as the research object,and with high-throughput sequencing to clarify the soil microbial diversity and community structure of five shrubs and their differences,redundancy analysis was used to study the relationship between soil physical and chemical factors and microbial communities,a preliminary analysis on soil microorganisms about the effect of planting different sand-fixing shrubs in straw checkerboard was made.The main research results and conclusions are as follows:1.The bacterial community of Corethrodendron fruticosum var.Mongolicum had the highest diversity,which was different from other plots(p<0.05).Caragana korshinskii had the highest fungal community diversity,and it had significant differences with Corethrodendron scoparium mixed with Calligonum mongonicum(p<0.05).2.The dominant bacteria,Actinobacteria,Acidobacteria,Proteobacteria and Chloroflexia,accounted for the highest proportion in Caragana korshinskii mixed with Corethrodendron scoparium,followed by Corethrodendron fruticosum var.Mongolicum.The dominant fungus,Ascomycota and Basidiomycota,had the highest proportion in Caragana korshinskii.3.Spearman correlation analysis showd that the relationship between environmental factors and the diversity index of bacterial community is that available potassium(AK)is positively correlated with ACE,Chao1,Observed,and negatively correlated with Coverage;pH is positively correlated with Coverage,and negatively correlated with ACE and Chao1;total potassium(TK)is positively correlated with Shannon index,total carbon(TC)is positively correlated with Shannon index,and negatively correlated with Simpson index.The relationship between environmental factors and fungal community diversity index is that AK,soil water(SW),electrical conductivity(EC)are negatively correlated with Coverage,and positively correlated with ACE,Chao1,Observed,and pH is negatively correlated with ACE,Chao1,and Observed.4.Results of redundancy analysis showd that SW and TC are positively correlated with Actinobacteria and Acidobacteria,and negatively correlated with Proteobacteria and Chloroflexi;AK,total nitrogen(TN)and Acidobacteria and Proteobacteria were positively correlated,and Actinobacteria and Chloroflexi were negatively correlated.SW is positively correlated with Ascomycota,and negatively correlated with Basidiomycota;TC is positively correlated with Basidiomycota,and negatively correlated with Ascomycota;available phosphorus(AP),pH are positively correlated with Ascomycota,and negatively correlated with Basidiomycota.