Changes of soil bacterial communities in bamboo plantations at different elevations

The effect of altitude on the distribution of plants and animals has been well studied. In contrast, the response of microbes to elevation is poorly understood. To determine whether soil bacterial communities respond to altitudinal gradients, moso bamboo forest soils along a gradient of six elevations from 600 to 1800 m were investigated using the barcoded pyrosequencing method. The results revealed that Acidobacteria and Proteobacteria predominated in the six communities, although the relative abundances were different. Non-metric multidimensional scaling analysis with the abundant OTUs showed that the community composition possessed a complex relationship with elevation. The communities at 1000 and 1200 m were similar and possessed higher levels of diversity than the communities at both lower and higher elevations, giving the diversity a hump-backed trend with elevation. By contrast, the soil C and N and microbial biomass properties increased linearly with elevation. Thus, the complex response of the bacterial community composition and diversity across elevation could not be explained as a simple response to elevation and presumably results from interactions between multiple factors such as soil organic matter content and temperature.