Co‐ordinated elevational diversity patterns for soil bacteria, fungi, and plants in alkaline soils of arid northwestern China

Abstract

AbstractPlants often show remarkable elevational distribution patterns in arid‐montane ecosystems. However, it is not clear if soil microbes follow elevational diversity patterns, even though they represent the majority of biodiversity and drive varieties of ecological processes. Here, we conducted a survey of fungal and bacterial communities across an elevational gradient from 2350 to 3850 m in a typical mountainous grassland of arid northwestern China. Our results revealed co‐ordinated alpha and beta diversity patterns for soil microbes and plants along the elevational gradient, and the richness and Shannon diversity of bacteria, fungi, and plants exhibited a unimodal elevational pattern. The unimodal diversity pattern for soil microbes was further confirmed by the shifts in the relative abundance of dominant bacterial phyla (Actinobacteria, Firmicutes and Nitrospirae) and fungal phyla (Zygomycota) along the elevational gradient. Soil variables (soil pH, organic carbon, total nitrogen, available phosphorus, and nitrate nitrogen) explained the largest proportion of the variability in both bacterial and fungal communities, followed by plant (richness and Shannon diversity) and climatic (mean annual temperature and precipitation) variables. These environmental factors together explained a larger proportion of variability in bacterial communities (54.88%) than in fungal communities (24.15%). Our results strongly supported the existence of co‐ordinated elevational diversity patterns for soil microbes and plants in arid‐montane ecosystems, and highlighted that the importance of soil pH in microbial elevational patterns was also apparently in alkaline soils.Highlights Soil bacteria and fungi follow elevational diversity patterns of plants. Species richness and Shannon diversity index exhibited unimodal elevational patterns. Soil, plant, and climatic factors are co‐responsible for microbial diversity. These factors explained more variation in bacteria than that in fungi. Microbial diversity is more vulnerable to precipitation than temperature.