Effects of Pear Pruning Branches Mulching on Soil Nutrition and Microbial Community Structures
[Objective]As a by-product of fruit tree shaping and pruning,pear branches are important biomass resources.The use of crushed branches for soil mulch under trees is one of the effective ways to utilize waste resources,which is conducive to increasing soil organic matter and improving soil fertility in pear orchards.[Method]In order to assess the effects of short-term pear branch mulching on soil properties and structure of microbial community,soil samples were collected from five pear orchards in different latitudes(Bijie City of Guizhou Province,Changli City of Hebei Province,Harbin City of Heilongjiang Province,Zhijiang City of Hubei Province and Xuchang City of Henan Province)after 1-2 years of mulching.Soil basic physiochemical characteristics of the soil and the bacterial,fungal and protist communities were detected.[Result]Results showed that the soil organic matter and available phosphorus content were significantly increased in pear branches mulching treatment in general,and the soil bacterial,fungal and protists community structure also changed significantly.Specifically,the mulching of pear branches significantly enriched the relative abundance of taxa such as Proteobacteria and Acidobacteria in bacteria,Basidiomycota in fungi,and Rhizaria and Alveolata in protists.The model prediction accuracy was as high as 94.44%,and the key species were mainly bacteria,including Acidibacter,Xanthobacteraceae,Nitrosomonadacee and other microorganisms related to the degradation of organic residues.Soil-available phosphorus content was found to be the main driver of variations in soil microbial community structure.[Conclusion]The study preliminarily assessed the effect of pear tree branch mulching on soil nutrients and microbiome and excavated potential key microorganisms.The findings can serve as a reference for managing the health and fertility of orchard soils.