Environmental data and OTU table of bacteria and fungi in Jianfengling, Shennongjia and Xing'an Mountains

Understanding the elevational pattern of soil microbial diversity is
crucial for microbial biogeography, yet, the elevational patterns of
diversity across different climatic zones, trophic levels and
taxonomic levels remain unclear. In this study, we investigated the
elevational patterns of species richness, evenness and the relationship
between species richness and evenness (RRE) in the forest soil bacterial
and fungal communities and individual phyla across three climatic zones
(tropical, subtropical and cold temperate). Our results revealed that soil
bacterial richness (alpha diversity) decreased with elevation, while fungi
richness exhibited a hump-shaped pattern in tropical and cold temperate
forests. Elevational patterns of evenness in bacterial and fungal
communities showed hump-shaped patterns across climatic zones, except
bacterial evenness in the tropical forest. Both bacterial and fungal
richness and evenness were positively correlated in the subtropical and
cold temperate forests, while negatively correlated for bacteria in the
tropical forest. The richness and evenness of soil microorganisms across
different regions were controlled by climatic and edaphic factors. Soil pH
was the most important factor associated with the variations in bacterial
richness and evenness, while mean annual temperature explained the major
variations in fungal richness. Our results addressed the varieties of
elevational patterns of microbial diversity in climate zones and taxonomic
levels, further indicating that richness and evenness may respond
differently to environmental gradients.