Effects Of Fertilization Length On Soil Microbial Community Structure And Diversity In Paulownia Plantations

Paulownia is our country commercial cultivation of fast-growing local plain broad leaved tree species,but in the south subtropical region of Paulownia are itsgreening tree species,land of south suitable for Paulowniahas larger potential,thus to explore human management measures such as fertilization effects on soil microbial community structure and diversity,can provide subtropical region of Paulownia plantation will provide a scientific basis for scientific fertilization and intensive management.This paper intends to study the changes of soil microbial community structure and diversity in Paulownia plantation under different years of fertilization in subtropical region,the relationship between soil microbial community structure and diversity in Paulownia plantation and basic soil properties,and the distribution law of dominant soil microbial population in Paulownia plantation.In evergreen broad-leaved forest,for comparison,this study in Xiangyin county,Hunan province set of four different fertilization(fertilize 1 year,3 years,10 years and 13 years)of Paulownia plantation fertilizing,the determination of 28 soil physical,chemical,microbial indicators,through high-throughput sequencing technology research of Paulownia plantation soil microflora and succession law,using clustering analysis and principal coordinate analysis to explore the differences between the soil microbial community structure under different processing,the use of redundancy analysis of Paulownia plantation soil microbial community structure and soil basic properties are analyzed,and the relationship between the full text summarized below(1)With the increase of fertilization years,the optimized ratio of soil bacterial community sample sequence is only 50%,while the optimized ratio of fungal community sample sequence reaches 98%.A total of 741465 valid sequences were detected in the bacterial community samples,with an average optimization rate of 45.48%.A total of 826904 effective sequences were measured in the fungal community samples,and the average optimization ratio reached 97.99%.The sequence optimization ratio and effective sequence number of the fungal community were significantly higher than that of the bacterial community,and from the richness index,the artificial forest treatment was higher than that of the evergreen broad-leaved forest.Bacterial(Shannon)diversity index,richness index(Chaol)and evenness index(Heip)are significantly different between plantation and evergreen broad-leaved forest(p<0.05).Fungal diversity index(Shannon)and richness index(Chaol)were significantly different between the treatment of plantation and evergreen broad-leaved forest(p<0.05).(2)The results of the study showed that the 3-yr and CK treatments of bacterial and fungal communities were significantly different from the 1-yr,10-yr,and 13-yr treatments.At the phylum level of the test forest,the dominant phylum of the different treatments was Chlorophyta,and the dominant bacterial genus was Acidothermus,Bradyrhizobium,etc.The soil of the experimental forest was at the phylum level,the dominant phylum of different treatments was Ascomycota,and the dominant genus of fungi were Chaetomium,Cladosporium,Fusarium,etc.The dominant bacteria in the soil bacterial community of Paulownia plantation are Chloroflexi(30.61%),Proteobacteria(24.18%),Acidobacteria(19.21%).The difference was significant in different treatments(p<0.05).The predominant phylums of fungi are Ascomycota(72.99%),Basidiomycota(14.52%),and Zygomtcota(5.13%).The Zygomycota are significantly different in different treatments(p<0.05).(3)Soil pH,total potassium,available potassium,organic matter,nitrate nitrogen,ammonia nitrogen,available boron,and available sulfur were significantly different between different Paulownia plantations(p<0.05).The urease activity and invertase activity were significantly different between the plantation treatment and the control group treatment(p<0.05),and the microbial biomass carbon,nitrogen,and phosphorus were significantly different between the plantation treatment and the control group treatment(p<0.05).(4)The soil chemical communities of Paulownia plantations with different fertilization years have significant correlations.The soil chemical indicators are total phosphorus,organic matter,and available boron,indicating that these factors are closely related to fertilization years.The results of the fungal community showed that total potassium,organic matter and available boron in different fertilization years were significantly related to the soil fungal community,indicating that these soil properties were closely related to the fertilization years.The extremely significant related factors shared by the diversity index of the bacterial community are soil clay content,available iron,available manganese,microbial biomass carbon,and microbial biomass phosphorus.The extremely significant related factors of soil fungal diversity index are soil clay content,available iron,microbial biomass phosphorus,and the extremely significant related factors of soil fungal richness index are soil clay content,ammonia nitrogen,available iron,available manganese,microbial biomass phosphorus However,the soil fungal uniformity index does not have a very significant correlation factor.All in all,the key limiting factors for soil microbial community structure are organic matter and available boron.The common limiting factors for bacterial and fungal diversity are clay content,available iron,and microbial biomass phosphorus.Iron and phosphorus can be added appropriately during fertilization management which elements can promote the growth and reproduction of beneficial microorganisms.