Response of Microbial Community Structure and Diversity to Nitrogen Deposition in Soils of Pinus yunnanensis Forest of the Central Yunnan Plateau
[Objective]To study the characteristics of changes in chemical properties and diversity and structural composition of soil microbial communities in Pinus yun-nanensis soils on the Central Yunnan Plateau under nitrogen deposition,and to analyze the correlation between soil microorganisms and soil chemical properties,in order to provide a scientific basis for understanding the trend of changes in nutrient cycling in forest soil ecosystems under nitrogen deposition and observing soil microbiological changes.[Method]The soil of P.yunnanensis forests on the Central Yunnan Plateau was selected as the research object,CO(NH2)2 was used as the N source,and four different gradients were set up for simulated N deposition experiments,including control CK[N 0 g/(m2·a)],low nitrogen LN[N 10 g/(m2·a)],medium nitrogen MN[N 20 g/(m2·a)],and high nitrogen HN[N 25 g/(m2·a)],the structure and diversity of soil bacterial and fungal community were analyzed,and the characteristics of the changes of soil pH,TOC,TN,TP,NH4+-N and NO3--N were determined.[Results](1)In both the dry and rainy seasons,soil pH and TOC content were reduced,and TN was increased under each N treatment when compared with CK,and both NH4+-N and NO3--N were increased at MN and HN compared to CK;(2)Both bacterial and fungal α-diversity were higher in the rainy season than in the dry season;bacterialα-diversity increased at LN under both seasons compared to CK,whereas fungi α-diversity increased at LN in the dry season;(3)In both the dry and rainy seasons,the dominant bacterial phyla were Proteobacteria,Acidobacteria and Actinobacteria,and the dominant fungal phyla were Basidiomycota,Ascomycota and Mortierellomycota;(4)The dominant bacterial and fungal genera were significantly correlated with pH,TOC,TN and NO3--N during the dry and wet seasons.[Conclusion]Nitrogen deposition can provide soil microorganisms with effective nutrients such as NH4+-N and NO3--N,but soil acidification due to nitrogen deposition can reduce soil TOC content and affect the structure of soil microbial communities.
Central Yunnan PlateauPinus yunnanensissoil microorganismsnitrogen deposition
万方数据
维普
