Differences In Microbial Communities And Metabolites In Litter Layers Of Two Types Of Korean Pine Forests

In order to explore the relationship between microbial diversity and metabolites in litter layer of Pinus koraiensis and Pinus koraiensis forest,the two types of litter layer microorganisms and metabolites were determined by high-throughput sequencing and metabolomics.The results were as follows:(1)Differences of physical and chemical indexes between two types of Korean pine forests.In terms of horizontal comparison,the contents of water content,organic carbon,total nitrogen and total phosphorus in the Artificial Korean pine forest were lower than those in the original Korean pine forest,and the contents of p H and total potassium were higher than those in the original Korean pine forest(P<0.05);the contents of water content(P<0.05).In terms of vertical comparison,p H,organic carbon,total phosphorus and total potassium in the lower layer of the Artificial Korean pine forest and the original Korean pine forest were higher than those in the middle layer(P<0.05),but the contents of total nitrogen were lower than those in the middle layer(P<0.05).(2)Differences of microbial community structure of two types of Korean pine forests.There were 698 bacterial genera(include Bacteroides ? Proteobacteria ?Alphaproteobacteria?Gammaproteobacteria and Subgroup?6)in the litter samples of Pinus koraiensis virgin forest.LEf Se analysis showed that there were 35 indicator bacteria,363 fungal genera(include Leotiomycetes?Golovinomyces?Mortierellaceae?Mucoromycota and Sarocladium)and 19 indicator bacteria;There were 622 bacterial genera(include Alphaproteobactria?Micropepsales?Micropepsaceae?Rhodanobacteraceae and Solibacterale)in the litter samples of Pinus koraiensis plantation.LEf Se analysis showed that there were 18 indicator bacteria,343 fungal genera(include Hypocreales?Chloridium?Xenopolyscytalum?Graphilbum and Polyscytalum)and 5 indicator bacteria;(3)Differences of metabolites of two types of Korean pine forests.There were 285 kinds of organic compounds in the two forest types,among which16 different metabolites were screened,including 5 kinds of organic acids(Palmitoleic acid ? 19(S)-HETE ? Phosphohydroxypyruvic acid ? Dodecanoic acid and D-1-Piperideine-2-carboxyli),4 kinds of amino acids(L-Alanine?Pyroglutamic acid?Saccharopine and Dimethylglycine),2 kinds of sugars(D-Fructose and D-Galactose),2kinds of sugar alcohols(5-Dehydroepisterol and Myo-Inositol),1 kind of lipid(Costunolide),1 kind of phenols(2-Aminophenol)and 1 kind of alkaloid(Sanguinarine).(4)Correlation analysis of microbial community structure and metabolites in two types of Korean pine forests.CCA analysis showed that the main metabolites associated with bacteria were saccharopine and pyroglutamic acid.In addition,saccharopine,D-fructose,dodecanoic acid and chitinophagaceae were significant correlation between the relative abundance of Chitinophagaceae?uncultured,SC-I-84?norank and Haliangium(P < 0.05).CCA analysis showed that the main metabolites associated with fungi were myo inositol and costunolide.In addition,inositol was significantly correlated with the relative abundance of Lactarius;costunolide was significantly correlated with the relative abundance of Graphilbum and Mytilinidion;D-galactose was significantly correlated with the relative abundance of Polyscytalum and Sporidesmium(P < 0.05).Latencibacteria,rokubacteria and olpidiomycota are unique to Pinus koraiensis virgin forest.They can catalyze litter degradation and have strong ability to decompose cellulose and chitin,respectively.Subgroup 6 of Acidobacteria.It is abundant in the lower layer of litter layer.It can grow on carbon compounds and participate in the metabolism of carbon compounds.It can be seen that the microbial diversity in the litter layer of Pinus koraiensis virgin forest is higher than that of artificial Pinus koraiensis forest,and the microbial diversity in the lower layer is higher than that in the middle layer.The microbial community structure in the litter layer of north temperate forest is closely related to the types of metabolites.The metabolites provide nutrition for microorganisms,and the specific microorganisms accelerate the degradation of macromolecular substances.At the same time,the difference of microbial community structure in litter layer between Pinus koraiensis virgin forest and artificial Pinus koraiensis forest also provides a theoretical basis for its participation in material cycle.