Soil bacterial diversity patterns and drivers along an elevational gradient on Shennongjia Mountain, China

Summary Understanding biological diversity elevational pattern and the driver factors are indispensable to develop the ecological theories. Elevational gradient may minimize the impact of environmental factors and is the ideal places to study soil microbial elevational patterns. In this study, we selected four typical vegetation types from 1000 to 2800 m above the sea level on the northern slope of S hennongjia Mountain in central C hina, and analysed the soil bacterial community composition, elevational patterns and the relationship between soil bacterial diversity and environmental factors by using the 16 S rRNA Illumina sequencing and multivariate statistical analysis. The results revealed that the dominant bacterial phyla were A cidobacteria , A ctinobacteria , A lphaproteobacteria , B etaproteobacteria , G ammaproteobacteria and V errucomicrobia , which accounted for over 75% of the bacterial sequences obtained from tested samples, and the soil bacterial operational taxonomic unit (OTU) richness was a significant monotonous decreasing ( P < 0.01) trend with the elevational increasing. The similarity of soil bacterial population composition decreased significantly ( P < 0.01) with elevational distance increased as measured by the J accard and B ray– C urtis index. Canonical correspondence analysis and M antel test analysis indicated that plant diversity and soil pH were significantly correlated ( P < 0.01) with the soil bacterial community. Therefore, the soil bacterial diversity on S hennongjia Mountain had a significant and different elevational pattern, and plant diversity and soil pH may be the key factors in shaping the soil bacterial spatial pattern.