Effects Of Wild Boar Grubbed On Soil Microbial Composition And Function

At present,the effects of large-scale wildlife activities are rarely considered in the study of soil carbon and nitrogen cycling in temperate forests.The influence of macrofauna on forest soil structure is mainly through the influence of soil microorganism and soil organic matter,which plays an important role in the formation of soil structure.In recent years,due to the influence of human activities on the wild boars feeding resources,the cover intensity of the ploughed land has increased year by year,especially in the broad-leaved Korean pine forest and Mongolian oak forest in northeast China.Wild boar grubbedr significantly affected soil biodiversity and carbon and nitrogen cycling in forest ecosystems.In this study,the composition and function of soil microbial community in a broad-leaved Korean pine forest were systematically studied by illumina-mise sequencing technique,the effect of wild boar grubbed on forest nitrogen conversion was also studied.The main results are as follows:(1)The grubbing of wild boar increased the concentration of ammonium and nitrate nitrogen,affected the soil nitrogen pool,and significantly promoted the soil nitrogen conversion rate(P < 0.05);It can improve the activity of diglycosidase and β-N-acetaminoglycosidase.(2)Proteobacteria,Actinobacteria and Acidobacteriota were the dominant phyla of soil bacterial communities in both grubbed and non-grubbed.The dominant phylum of soil fungi were Basidiomycota and Ascomycota,and the dominant phylum of soil protozoa was Opisthokonta.At the beginning of the growing season,the relative abundance of Verrucomicrobia and Gemmatimonadetes increased(34.15%,5.07%),and both were negatively correlated with soil nitrogen content.Grubbing reduced the relative abundance of Acidothermus and Candidatus Solibacter(12.53%,4.90%),and was negatively correlated with p H.The relative abundance of Ascomycota increased by 4.91% after grubbing.After grubbing,the species richness of soil protozoa increased and the community was more stable.The dominant phylum was Opisthokonta,and in October 2019,the relative abundance of Amoebozoa increased by 26.26% due to grubbing by wild boar.The results of redundancy analysis showed that p H was one of the dominant factors(45.1%;34.4%),which explained 13.2% and 10.5% of the variation of bacterial and fungal communities,respectively.(3)FAPROTAX was used to predict the function of soil bacterial community,and the results showed that arching enhanced nitrogen fixation.This may be due to the increased relative abundance of Bradyrhizobium,which is involved in soil nitrogen fixation.Fun Guild was used to predict the function of soil fungi under grubbing and non-grubbing.The results showed that the abundance of soil pathogens decreased after grubbing,suggesting that grubbing may contribute to ecosystem health.(4)After grubbing,the bacterial and fungal communities in the soil were more easily affected by the external environment,and their stability was weaker,while the species richness of protozoa increased and the community was more stable.The results showed that overgrubbing of wild boar changed the relative abundance of some important microbial functional groups and promoted nitrogen conversion.These results emphasize the important effects of wild boar grubbed on soil nitrogen transformation and soil microbial diversity,and are important for accurately assessing the effects of wild boar grubbed on forest ecosystem function,at the same time,it also provides some enlightenment for forest ecosystem management.